Data commit

Task/Calendar/00-META.yaml

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+---
+category:
+- Scala examples needing attention
+from: http://rosettacode.org/wiki/Calendar
+note: Date and time

Task/Calendar/00-TASK.txt

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+Create a routine that will generate a text calendar for any year.  
+Test the calendar by generating a calendar for the year 1969, on a device of the time. 
+Choose one of the following devices:
+
+* A line printer with a width of 132 characters.
+* An [[wp:IBM_3270#Displays|IBM 3278 model 4 terminal]] (80×43 display with accented characters). Target formatting the months of the year to fit nicely across the 80 character width screen. Restrict number of lines in test output to 43.
+
+
+(Ideally, the program will generate well-formatted calendars for any page width from 20 characters up.)
+
+Kudos (κῦδος) for routines that also transition from [https://en.wikipedia.org/wiki/Julian_calendar Julian] to [https://en.wikipedia.org/wiki/Gregorian_calendar Gregorian calendar].
+
+This task is inspired by [http://www.ee.ryerson.ca/~elf/hack/realmen.html Real Programmers Don't Use PASCAL] by Ed Post, Datamation, volume 29 number 7, July 1983.
+ THE REAL PROGRAMMER'S NATURAL HABITAT
+ "Taped to the wall is a line-printer Snoopy calender for the year 1969."
+For further Kudos see task [[Calendar - for "real" programmers|CALENDAR]], where all code is to be in UPPERCASE.
+
+For economy of size, do not actually include Snoopy generation in either the code or the output, instead just output a place-holder.
+
+
+;Related task:
+:*   [[Five weekends]]
+<br><br>

Task/Calendar/360-Assembly/calendar.360

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+*        calendar                  08/06/2016
+CALENDAR CSECT
+         USING  CALENDAR,R13       base register
+         B      72(R15)            skip savearea
+         DC     17F'0'             savearea
+         STM    R14,R12,12(R13)    prolog
+         ST     R13,4(R15)         "
+         ST     R15,8(R13)         "
+         LR     R13,R15            "
+         L      R4,YEAR            year
+         SRDA   R4,32              .
+         D      R4,=F'4'           year//4
+         LTR    R4,R4              if year//4=0
+         BNZ    LYNOT
+         L      R4,YEAR            year
+         SRDA   R4,32              .
+         D      R4,=F'100'         year//100
+         LTR    R4,R4              if year//100=0
+         BNZ    LY
+         L      R4,YEAR            year
+         SRDA   R4,32              .
+         D      R4,=F'400'         if year//400
+         LTR    R4,R4              if year//400=0
+         BNZ    LYNOT
+LY       MVC    ML+2,=H'29'        ml(2)=29  leapyear
+LYNOT    SR     R10,R10            ltd1=0
+         LA     R6,1               i=1
+LOOPI1   C      R6,=F'31'          do i=1 to 31
+         BH     ELOOPI1
+         XDECO  R6,XDEC            edit i
+         LA     R14,TD1            td1
+         AR     R14,R10            td1+ltd1
+         MVC    0(3,R14),XDEC+9    sub(td1,ltd1+1,3)=pic(i,3)
+         LA     R10,3(R10)         ltd1+3
+         LA     R6,1(R6)           i=i+1
+         B      LOOPI1
+ELOOPI1  LA     R6,1               i=1
+LOOPI2   C      R6,=F'12'          do i=1 to 12
+         BH     ELOOPI2
+         ST     R6,M               m=i
+         MVC    D,=F'1'            d=1
+         MVC    YY,YEAR            yy=year
+         L      R4,M               m
+         C      R4,=F'3'           if m<3
+         BNL    GE3
+         L      R2,M               m
+         LA     R2,12(R2)          m+12
+         ST     R2,M               m=m+12
+         L      R2,YY              yy
+         BCTR   R2,0               yy-1
+         ST     R2,YY              yy=yy-1
+GE3      L      R2,YY              yy
+         LR     R1,R2              yy
+         SRA    R1,2               yy/4
+         AR     R2,R1              yy+(yy/4)
+         L      R4,YY              yy
+         SRDA   R4,32              .
+         D      R4,=F'100'         yy/100
+         SR     R2,R5              yy+(yy/4)-(yy/100)
+         L      R4,YY              yy
+         SRDA   R4,32              .
+         D      R4,=F'400'         yy/400
+         AR     R2,R5              yy+(yy/4)-(yy/100)+(yy/400)
+         A      R2,D               r2=yy+(yy/4)-(yy/100)+(yy/400)+d
+         LA     R5,153             153
+         M      R4,M               153*m
+         LA     R5,8(R5)           153*m+8
+         D      R4,=F'5'           (153*m+8)/5
+         AR     R5,R2              ((153*m+8)/5+r2
+         LA     R4,0               .
+         D      R4,=F'7'           r4=mod(r5,7)  0=sun 1=mon ... 6=sat
+         LTR    R4,R4              if j=0
+         BNZ    JNE0
+         LA     R4,7               j=7
+JNE0     BCTR   R4,0               j-1
+         MH     R4,=H'3'           j*3
+         LR     R10,R4             j1=j*3
+         LR     R1,R6              i
+         SLA    R1,1               *2
+         LH     R11,ML-2(R1)       ml(i)
+         MH     R11,=H'3'          j2=ml(i)*3
+         MVC    TD2,BLANK          td2=' '
+         LA     R4,TD1             @td1
+         LR     R5,R11             j2
+         LA     R2,TD2             @td2
+         AR     R2,R10             @td2+j1
+         LR     R3,R5              j2
+         MVCL   R2,R4              sub(td2,j1+1,j2)=sub(td1,1,j2)
+         LR     R1,R6              i
+         MH     R1,=H'144'         *144
+         LA     R14,DA-144(R1)     @da(i)
+         MVC    0(144,R14),TD2     da(i)=td2
+         LA     R6,1(R6)           i=i+1
+         B      LOOPI2
+ELOOPI2  L      R1,YEAR            year
+         XDECO  R1,PG+23           edit year
+         XPRNT  PG,35              print year
+         MVC    WDLINE,BLANK       wdline=' '
+         LA     R10,1              lwdline=1
+         LA     R8,1               k=1
+LOOPK3   C      R8,=F'3'           do k=1 to 3
+         BH     ELOOPK3
+         LA     R4,WDLINE          @wdline
+         AR     R4,R10             +lwdline
+         MVC    0(20,R4),WDNA      sub(wdline,lwdline+1,20)=wdna
+         LA     R10,20(R10)        lwdline=lwdline+20
+         C      R8,=F'3'           if k<3
+         BNL    ITERK3
+         LA     R10,2(R10)         lwdline=lwdline+2
+ITERK3   LA     R8,1(R8)           k=k+1
+         B      LOOPK3
+ELOOPK3  LA     R6,1               i=1
+LOOPI4   C      R6,=F'12'          do i=1 to 12 by 3
+         BH     ELOOPI4
+         MVC    MOLINE,BLANK       moline=' '
+         LA     R10,6              lmoline=6
+         LR     R8,R6              k=i
+LOOPK4   LA     R2,2(R6)           i+2
+         CR     R8,R2              do k=i to i+2
+         BH     ELOOPK4
+         LR     R1,R8              k
+         MH     R1,=H'10'          *10
+         LA     R3,MO-10(R1)       mo(k)
+         LA     R4,MOLINE          @moline
+         AR     R4,R10             +lmoline
+         MVC    0(10,R4),0(R3)     sub(moline,lmoline+1,10)=mo(k)
+         LA     R10,22(R10)        lmoline=lmoline+22
+         LA     R8,1(R8)           k=k+1
+         B      LOOPK4
+ELOOPK4  XPRNT  MOLINE,L'MOLINE    print months
+         XPRNT  WDLINE,L'WDLINE    print days of week
+         LA     R7,1               j=1
+LOOPJ4   C      R7,=F'106'         do j=1 to 106 by 21
+         BH     ELOOPJ4
+         MVC    PG,BLANK           clear buffer
+         LA     R9,PG              pgi=0
+         LR     R8,R6              k=i
+LOOPK5   LA     R2,2(R6)           i+2
+         CR     R8,R2              do k=i to i+2
+         BH     ELOOPK5
+         LR     R1,R8              k
+         MH     R1,=H'144'         *144
+         LA     R4,DA-144(R1)      da(k)
+         BCTR   R4,0               -1
+         AR     R4,R7              +j
+         MVC    0(21,R9),0(R4)     substr(da(k),j,21)
+         LA     R9,22(R9)          pgi=pgi+22
+         LA     R8,1(R8)           k=k+1
+         B      LOOPK5
+ELOOPK5  XPRNT  PG,L'PG            print buffer
+         LA     R7,21(R7)          j=j+21
+         B      LOOPJ4
+ELOOPJ4  LA     R6,3(R6)           i=i+3
+         B      LOOPI4
+ELOOPI4  L      R13,4(0,R13)       epilog
+         LM     R14,R12,12(R13)    "
+         XR     R15,R15            "
+         BR     R14                exit
+         LTORG
+YEAR     DC     F'1969'            <==
+MO       DC     CL10' January  ',CL10' February ',CL10'  March   '
+         DC     CL10'  April   ',CL10'   May    ',CL10'   June   '
+         DC     CL10'   July   ',CL10'  August  ',CL10'September '
+         DC     CL10' October  ',CL10' November ',CL10' December '
+ML       DC     H'31',H'28',H'31',H'30',H'31',H'30'
+         DC     H'31',H'31',H'30',H'31',H'30',H'31'
+WDNA     DC     CL20'Mo Tu We Th Fr Sa Su'
+M        DS     F
+D        DS     F
+YY       DS     F
+TD1      DS     CL93
+TD2      DS     CL144
+MOLINE   DS     CL66
+WDLINE   DS     CL66
+PG       DC     CL66' '
+XDEC     DS     CL12
+BLANK    DC     CL144' '
+DA       DS     12CL144
+         YREG
+         END    CALENDAR

Task/Calendar/ALGOL-68/calendar.alg

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+#!/usr/local/bin/a68g --script #
+
+PROC print calendar = (INT year, page width)VOID: (
+
+  []STRING month names = (
+      "January","February","March","April","May","June",
+      "July","August","September","October","November","December"),
+    weekday names = ("Su","Mo","Tu","We","Th","Fr","Sa");
+  FORMAT weekday fmt = $g,n(UPB weekday names - LWB weekday names)(" "g)$;
+
+  # Juggle the calendar format to fit the printer/screen width #
+  INT day width = UPB weekday names[1], day gap=1;
+  INT month width = (day width+day gap) * UPB weekday names-1;
+  INT month heading lines = 2;
+  INT month lines = (31 OVER UPB weekday names+month heading lines+2); # +2 for head/tail weeks #
+  INT year cols = (page width+1) OVER (month width+1);
+  INT year rows = (UPB month names-1)OVER year cols + 1;
+  INT month gap = (page width - year cols*month width + 1)OVER year cols;
+  INT year width = year cols*(month width+month gap)-month gap;
+  INT year lines = year rows*month lines;
+
+  MODE MONTHBOX = [month lines, month width]CHAR;
+  MODE YEARBOX  = [year  lines, year  width]CHAR;
+
+  INT week start = 1; # Sunday #
+
+  PROC days in month = (INT year, month)INT:
+    CASE month IN 31,
+      IF year MOD 4 EQ 0 AND year MOD 100 NE 0 OR year MOD 400 EQ 0 THEN 29 ELSE 28 FI,
+      31, 30, 31, 30, 31, 31, 30, 31, 30, 31
+    ESAC;
+
+  PROC day of week = (INT year, month, day)INT: (
+    # Day of the week by Zeller’s Congruence algorithm from 1887 #
+    INT y := year, m := month, d := day, c;
+    IF m <= 2 THEN m +:= 12; y -:= 1 FI;
+    c := y OVER 100;
+    y %*:= 100;
+    (d - 1 + ((m + 1) * 26) OVER 10 + y + y OVER 4 + c OVER 4 - 2 * c) MOD 7
+  );
+
+  MODE SIMPLEOUT = UNION(STRING, []STRING, INT);
+
+  PROC cputf = (REF[]CHAR out, FORMAT fmt, SIMPLEOUT argv)VOID:(
+    FILE f; STRING s; associate(f,s);
+    putf(f, (fmt, argv));
+    out[:UPB s]:=s;
+    close(f)
+  );
+
+  PROC month repr = (INT year, month)MONTHBOX:(
+    MONTHBOX month box; FOR line TO UPB month box DO month box[line,]:=" "* 2 UPB month box OD;
+    STRING month name = month names[month];
+
+  # center the title #
+    cputf(month box[1,(month width - UPB month name ) OVER 2+1:], $g$, month name);
+    cputf(month box[2,], weekday fmt, weekday names);
+
+    INT first day := day of week(year, month, 1);
+    FOR day TO days in month(year, month) DO
+      INT line = (day+first day-week start) OVER UPB weekday names + month heading lines + 1;
+      INT char =((day+first day-week start) MOD UPB weekday names)*(day width+day gap) + 1;
+      cputf(month box[line,char:char+day width-1],$g(-day width)$, day)
+    OD;
+    month box
+  );
+
+  PROC year repr = (INT year)YEARBOX:(
+    YEARBOX year box;
+    FOR line TO UPB year box DO year box[line,]:=" "* 2 UPB year box OD;
+    FOR month row FROM 0 TO year rows-1 DO
+      FOR month col FROM 0 TO year cols-1 DO
+        INT month = month row * year cols + month col + 1;
+        IF month > UPB month names THEN
+          done
+        ELSE
+          INT month col width = month width+month gap;
+          year box[
+            month row*month lines+1 : (month row+1)*month lines,
+            month col*month col width+1 : (month col+1)*month col width-month gap
+          ] := month repr(year, month)
+        FI
+      OD
+    OD;
+    done: year box
+  );
+
+  INT center = (year cols*(month width+month gap) - month gap - 1) OVER 2;
+  INT indent = (page width - year width) OVER 2;
+
+  printf((
+    $n(indent + center - 9)k  g l$, "[Insert Snoopy here]",
+    $n(indent + center - 1)k 4d l$, year, $l$,
+    $n(indent)k n(year width)(g)  l$, year repr(year)
+  ))
+);
+
+main: (
+CO inspired by http://www.ee.ryerson.ca/~elf/hack/realmen.html
+           Real Programmers Don't Use PASCAL - Ed Post
+            Datamation, volume 29 number 7, July 1983
+              THE REAL PROGRAMMER'S NATURAL HABITAT
+"Taped to the wall is a line-printer Snoopy calender for the year 1969."
+CO
+  INT mankind stepped on the moon = 1969,
+      line printer width = 80; # as at 1969! #
+  print calendar(mankind stepped on the moon, line printer width)
+)

Task/Calendar/ALGOL-W/calendar.alg

@@ -0,0 +1,142 @@
+BEGIN
+    INTEGER WIDTH, YEAR;
+    INTEGER COLS, LEAD, GAP;
+    STRING(2) ARRAY WDAYS (0::6);
+    RECORD MONTH ( STRING(9) MNAME; INTEGER DAYS, START_WDAY, AT_POS );
+    REFERENCE(MONTH) ARRAY MONTHS(0::11);
+    WIDTH := 80; YEAR := 1969;
+
+    BEGIN
+        WDAYS(0) := "Su"; WDAYS(1) := "Mo"; WDAYS(2) := "Tu";
+        WDAYS(3) := "We"; WDAYS(4) := "Th"; WDAYS(5) := "Fr"; WDAYS(6) := "Sa";
+        MONTHS( 0) := MONTH(" January",  31, 0, 0 );
+        MONTHS( 1) := MONTH(" February", 28, 0, 0 );
+        MONTHS( 2) := MONTH("  March",   31, 0, 0 );
+        MONTHS( 3) := MONTH("  April",   30, 0, 0 );
+        MONTHS( 4) := MONTH("   May",    31, 0, 0 );
+        MONTHS( 5) := MONTH("   June",   30, 0, 0 );
+        MONTHS( 6) := MONTH("   July",   31, 0, 0 );
+        MONTHS( 7) := MONTH("  August",  31, 0, 0 );
+        MONTHS( 8) := MONTH("September", 30, 0, 0 );
+        MONTHS( 9) := MONTH(" October",  31, 0, 0 );
+        MONTHS(10) := MONTH(" November", 30, 0, 0 );
+        MONTHS(11) := MONTH(" December", 31, 0, 0 )
+    END;
+
+    BEGIN
+
+        PROCEDURE SPACE(INTEGER VALUE N);
+        BEGIN
+            WHILE N > 0 DO BEGIN
+                WRITEON(" "); N := N-1;
+            END
+        END SPACE;
+
+        PROCEDURE INIT_MONTHS;
+        BEGIN
+            INTEGER I;
+
+            IF YEAR REM 4 = 0 AND YEAR REM 100 NOT = 0 OR YEAR REM 400 = 0 THEN
+                DAYS(MONTHS(1)) := 29;
+
+            YEAR := YEAR-1;
+            START_WDAY(MONTHS(0))
+                := (YEAR * 365 + YEAR DIV 4 - YEAR DIV 100 + YEAR DIV 400 + 1) REM 7;
+
+            FOR I := 1 STEP 1 UNTIL 12-1 DO
+                START_WDAY(MONTHS(I)) :=
+                    (START_WDAY(MONTHS(I-1)) + DAYS(MONTHS(I-1))) REM 7;
+
+            COLS := (WIDTH + 2) DIV 22;
+            WHILE 12 REM COLS NOT = 0 DO
+                COLS := COLS-1;
+            GAP := IF COLS - 1 NOT = 0 THEN (WIDTH - 20 * COLS) DIV (COLS - 1) ELSE 0;
+            IF GAP > 4 THEN
+                GAP := 4;
+            LEAD := (WIDTH - (20 + GAP) * COLS + GAP + 1) DIV 2;
+            YEAR := YEAR+1
+        END INIT_MONTHS;
+
+        PROCEDURE PRINT_ROW(INTEGER VALUE ROW);
+        BEGIN
+            INTEGER C, I, FROM, UP_TO;
+            INTEGER PROCEDURE PREINCREMENT(INTEGER VALUE RESULT I);
+            BEGIN I := I+1; I
+            END PREINCREMENT;
+            INTEGER PROCEDURE POSTINCREMENT(INTEGER VALUE RESULT I);
+            BEGIN INTEGER PREV_VALUE;
+                PREV_VALUE := I; I := I+1; PREV_VALUE
+            END POSTINCREMENT;
+            FROM := ROW * COLS;
+            UP_TO := FROM + COLS;
+            SPACE(LEAD);
+            FOR C := FROM STEP 1 UNTIL UP_TO-1 DO BEGIN
+                I := 9 % LENGTH OF MNAME(MONTHS(C)) % ;
+                SPACE((20 - I) DIV 2);
+                WRITEON(MNAME(MONTHS(C)));
+                SPACE(20 - I - (20 - I) DIV 2 + (IF C = UP_TO - 1 THEN 0 ELSE GAP));
+            END;
+            WRITE();
+
+            SPACE(LEAD);
+            FOR C := FROM STEP 1 UNTIL UP_TO-1 DO BEGIN
+                FOR I := 0 STEP 1 UNTIL 7-1 DO BEGIN
+                    WRITEON(WDAYS(I)); IF I NOT = 6 THEN WRITEON(" ")
+                END;
+                IF C < UP_TO - 1 THEN
+                    SPACE(GAP)
+                ELSE
+                    WRITE();
+            END;
+            WHILE BEGIN
+                C := FROM;
+                WHILE C < UP_TO AND AT_POS(MONTHS(C)) >= DAYS(MONTHS(C)) DO
+                    C := C + 1;
+
+                C NOT = UP_TO
+            END DO BEGIN
+
+                SPACE(LEAD);
+                C := FROM;
+                WHILE C < UP_TO DO BEGIN
+                    I := 0;
+                    WHILE I < START_WDAY(MONTHS(C)) DO BEGIN
+                        I := I + 1;
+                        SPACE(3)
+                    END;
+                    WHILE POSTINCREMENT(I) < 7 AND AT_POS(MONTHS(C)) < DAYS(MONTHS(C)) DO BEGIN
+                        WRITEON(I_W := 2, S_W := 0, PREINCREMENT(AT_POS(MONTHS(C))));
+                        IF I < 7 OR C < UP_TO - 1 THEN
+                            SPACE(1)
+                    END;
+                    WHILE POSTINCREMENT(I) <= 7 AND C < UP_TO-1 DO
+                        SPACE(3);
+                    IF C < UP_TO - 1 THEN
+                        SPACE(GAP - 1);
+                    START_WDAY(MONTHS(C)) := 0;
+                    C := C + 1
+                END;
+                WRITE();
+            END;
+            WRITE()
+        END PRINT_ROW;
+
+        PROCEDURE PRINT_YEAR;
+        BEGIN
+            INTEGER ROW, STRLEN, Y;
+            STRLEN := 1;
+            Y      := YEAR;
+            WHILE Y > 9 DO BEGIN Y := Y DIV 10; STRLEN := STRLEN + 1 END;
+            SPACE((WIDTH - STRLEN) DIV 2);
+            WRITEON(I_W := 1, YEAR);
+            WRITE(); WRITE();
+            WHILE ROW * COLS < 12 DO BEGIN
+                PRINT_ROW(ROW);
+                ROW := ROW+1
+            END
+        END PRINT_YEAR;
+
+        INIT_MONTHS;
+        PRINT_YEAR
+    END
+END.

Task/Calendar/AWK/calendar.awk

@@ -0,0 +1,97 @@
+Works with Gnu awk version 3.1.5 and with BusyBox v1.20.0.git awk
+To change the output width, change the value assigned to variable pagewide
+
+#!/bin/gawk -f
+BEGIN{
+  wkdays = "Su Mo Tu We Th Fr Sa"
+  pagewide = 80
+  blank=" "
+  for (i=1; i<pagewide; i++) blank = blank " "
+  #  month name accessed as substr(month,num*10,10)
+  #      where num is number of month, 1-12
+  month= "           January  February    March     April  "
+  month=    month "   May      June       July     August  "
+  month=    month " September October   November  December "
+  #  table of days per month accessed as substr(days,2*month,2)
+  days =" 312831303130313130313031"
+  line1 = ""
+  line2 = ""
+  line3 = ""
+  line4 = ""
+  line5 = ""
+  line6 = ""
+  line7 = ""
+  line8 = ""
+# print " year: " year " starts on: " dow(year)
+  }
+function center(text,   half) {
+  half = (pagewide - length(text))/2
+  return substr(blank,1,half) text substr(blank,1,half)
+  }
+function min(a,b) {
+  if (a < b) return a
+  else return b
+  }
+function makewk (fst,lst,day,  i,wstring ){
+  wstring=""
+  for (i=1;i<day;i++) wstring=wstring "   "
+  for (i=fst;i<=lst;i++) wstring=wstring sprintf("%2d ",i)
+  return substr(wstring "                     ",1,20)
+  }
+function dow (year, y){
+  y=year
+  y= (y*365+int(y/4) - int(y/100) + int(y/400) +1) %7
+# leap year adjustment
+  leap = 0
+  if (year % 4 == 0)   leap = 1
+  if (year % 100 == 0) leap = 0
+  if (year % 400 == 0) leap = 1
+  y = y - leap
+  if (y==-1) y=6
+  if (y==0) y=7
+  return (y)
+  }
+function prmonth (nmonth, newdow,monsize  ){
+  line1 = line1  "     " (substr(month,10*nmonth,10)) "       "
+  line2 = line2  (wkdays) "  "
+  line3 = line3  (makewk(1,8-newdow,newdow)) "  "
+  line4 = line4  (makewk(9-newdow,15-newdow,1)) "  "
+  line5 = line5  (makewk(16-newdow,22-newdow,1)) "  "
+  line6 = line6  (makewk(23-newdow,29-newdow,1)) "  "
+  line7 = line7  (makewk(30-newdow,min(monsize,36-newdow),1)) "  "
+  line8 = line8  (makewk(37-newdow,monsize,1)) "  "
+if (length(line3) + 22 > pagewide) {
+  print center(line1)
+  print center(line2)
+  print center(line3)
+  print center(line4)
+  print center(line5)
+  print center(line6)
+  print center(line7)
+  print center(line8)
+  line1 = ""
+  line2 = ""
+  line3 = ""
+  line4 = ""
+  line5 = ""
+  line6 = ""
+  line7 = ""
+  line8 = ""
+  }
+}
+/q/{
+  exit }
+{
+  monsize=substr(days,2*1,2)
+  newdow=dow($1)
+  print center("[ picture of Snoopy goes here ]")
+  print center(sprintf("%d",$1)  )
+  # January - December
+  for (i=1; i<13; i++) {
+  prmonth(i,newdow,monsize)
+  newdow=(monsize+newdow) %7
+  if (newdow == 0) newdow = 7
+  monsize=substr(days,2+2*i,2)
+  if (leap == 1 && monsize == 28) monsize = 29
+  }
+ }

Task/Calendar/Ada/calendar-1.ada

@@ -0,0 +1,48 @@
+with Ada.Calendar.Formatting;
+
+package Printable_Calendar is
+
+   subtype String20 is String(1 .. 20);
+   type Month_Rep_Type is array (Ada.Calendar.Month_Number) of String20;
+
+   type Description is record
+      Weekday_Rep: String20;
+      Month_Rep: Month_Rep_Type;
+   end record;
+   -- for internationalization, you only need to define a new description
+
+   Default_Description: constant Description :=
+     (Weekday_Rep =>
+       "Mo Tu We Th Fr Sa So",
+      Month_Rep   =>
+      ("      January       ", "      February      ", "       March        ",
+       "       April        ", "        May         ", "        June        ",
+       "        July        ", "       August       ", "      September     ",
+       "       October      ", "      November      ", "      December      "));
+
+   type Calendar (<>) is tagged private;
+
+   -- Initialize a calendar for devices with 80- or 132-characters per row
+   function Init_80(Des: Description := Default_Description) return Calendar;
+   function Init_132(Des: Description := Default_Description) return Calendar;
+
+   -- the following procedures output to standard IO; override if neccessary
+   procedure New_Line(Cal: Calendar);
+   procedure Put_String(Cal: Calendar; S: String);
+
+   -- the following procedures do the real stuff
+   procedure Print_Line_Centered(Cal: Calendar'Class; Line: String);
+   procedure Print(Cal: Calendar'Class;
+                   Year:  Ada.Calendar.Year_Number;
+                   Year_String: String); -- this is the main Thing
+
+private
+      type Calendar is tagged record
+      Columns, Rows, Space_Between_Columns: Positive;
+      Left_Space: Natural;
+
+      Weekday_Rep: String20;
+      Month_Rep: Month_Rep_Type;
+   end record;
+
+end Printable_Calendar;

Task/Calendar/Ada/calendar-2.ada

@@ -0,0 +1,176 @@
+with Ada.Text_IO;
+
+package body Printable_Calendar is
+
+   use Ada.Calendar;
+   package F renames Ada.Calendar.Formatting;
+
+   function Days_Per_Month(Year: Year_Number; Month: Month_Number)
+                          return Day_Number is
+   begin
+      case Month is
+         when 1 | 3 | 5 | 7 | 8 | 10 | 12 => return 31;
+         when 4 | 6 | 9 | 11              => return 30;
+         when 2 =>
+            if Year mod 4 /= 0 then
+               return 28;
+            elsif Year mod 100 /= 0 then
+               return 29;
+            elsif Year mod 400 /= 0 then
+               return 28;
+            else
+               return 29;
+            end if;
+      end case;
+   end Days_Per_Month;
+
+   type Full_Month_Rep is array (1 .. 6) of String20;
+   function Generate_Printable_Month (Y: Ada.Calendar.Year_Number;
+                                      M: Ada.Calendar.Month_Number)
+                                     return Full_Month_Rep is
+
+      X: Full_Month_Rep := (others => "                    ");
+      -- If X=Generate_Printable_Month(2011, 01), the result could be
+      --  "       January      ", -- Month_Rep(01)
+      --  "Mo Tu We Th Fr Sa Su"  -- Weekday_Rep
+      --  "                1  2"  -- X(1)
+      --  " 3  4  5  6  7  8  9"  -- X(2)
+      --  "10 11 12 13 14 15 16"  -- X(3)
+      --  "17 18 19 20 21 22 23"  -- X(4)
+      --  "24 25 26 27 28 29 30"  -- X(5)
+      --  "31                  "  -- X(6)
+
+      Row:       Integer range 1 .. 6  := 1;
+      Day_Index: constant array(F.Day_Name) of Positive
+        := (1, 4, 7, 10, 13, 16, 19);
+   begin
+      for I in 1 .. Days_Per_Month(Y, M) loop
+         declare
+           Weekday: constant F.Day_Name    := F.Day_Of_Week(F.Time_Of(Y, M, I));
+           Pos: constant Positive          := Day_Index(Weekday);
+           Cleartext_Name: constant String := Day_Number'Image(I);
+           L: constant Positive            := Cleartext_Name'Last;
+         begin
+            X(Row)(Pos .. Pos+1) := Cleartext_Name(L-1 .. L);
+            if F."="(Weekday, F.Sunday) then
+               Row := Row + 1;
+            end if;
+         end;
+      end loop;
+      return X;
+   end Generate_Printable_Month;
+
+
+   procedure Print(Cal: Calendar'class;
+                   Year:  Ada.Calendar.Year_Number;
+                   Year_String: String) is
+
+      The_Month: Month_Number := Month_Number'First;
+
+      procedure Write_Space(Length: Natural) is
+      begin
+         for I in 1 .. Length loop
+            Cal.Put_String(" ");
+         end loop;
+      end Write_Space;
+
+      Year_Rep: array(Month_Number) of Full_Month_Rep;
+
+   begin
+      -- print the year
+      Cal.Print_Line_Centered(Year_String);
+
+      -- generate a printable form for all the months
+      for Month in Month_Number loop
+         Year_Rep(Month) := Generate_Printable_Month(Year, Month);
+      end loop;
+
+      begin
+         while True loop
+
+            -- new line
+            Cal.New_Line;
+
+            -- write month names
+            Write_Space(Cal.Left_Space);
+            for Month in The_Month .. The_Month+Cal.Columns-2 loop
+               Cal.Put_String(Cal.Month_Rep(Month));
+               Write_Space(Cal.Space_Between_Columns);
+            end loop;
+            Cal.Put_String(Cal.Month_Rep(The_Month+Cal.Columns-1));
+            Cal.New_Line;
+
+            -- write "Mo Tu .. So" - or whatever is defined by Weekday_Rep
+            Write_Space(Cal.Left_Space);
+            for Month in The_Month .. The_Month+Cal.Columns-2 loop
+               Cal.Put_String(Cal.Weekday_Rep);
+               Write_Space(Cal.Space_Between_Columns);
+            end loop;
+            Cal.Put_String(Cal.Weekday_Rep);
+            Cal.New_Line;
+
+            -- write the dates
+            for I in 1 .. 6 loop
+               Write_Space(Cal.Left_Space);
+               for Month in The_Month .. The_Month+Cal.Columns-2 loop
+                  Cal.Put_String(Year_Rep(Month)(I));
+                  Write_Space(Cal.Space_Between_Columns);
+               end loop;
+            Cal.Put_String(Year_Rep(The_Month+Cal.Columns-1)(I));
+            Cal.New_Line;
+            end loop;
+
+            The_Month := The_Month + Cal.Columns;
+            -- this will eventually raise Constraint_Error to terminate the loop
+         end loop;
+      exception
+         when Constraint_Error => null;
+      end;
+   end Print;
+
+   procedure New_Line(Cal: Calendar) is
+   begin
+      Ada.Text_IO.New_Line;
+   end New_Line;
+
+   procedure Put_String(Cal: Calendar; S: String) is
+   begin
+      Ada.Text_IO.Put(S);
+   end Put_String;
+
+   procedure Print_Line_Centered(Cal: Calendar'Class; Line: String) is
+      Width : constant Positive := Cal.Columns*20
+        + (Cal.Columns-1)*Cal.Space_Between_Columns
+        + Cal.Left_Space;
+   begin
+      if Line'Length    >= Width-1 then
+         Cal.Put_String(Line);
+         Cal.New_Line;
+      else
+         Print_Line_Centered(Cal, " " & Line & " ");
+      end if;
+   end Print_Line_Centered;
+
+   function Init_80(Des: Description := Default_Description) return Calendar is
+      X: Calendar:=
+        (Columns => 3, Rows => 4, Space_Between_Columns => 4,
+         Left_Space => 1,
+         Weekday_Rep =>  Des.Weekday_Rep,
+         Month_Rep   =>  Des.Month_Rep
+        );
+   begin
+      return X;
+   end Init_80;
+
+   function Init_132(Des: Description := Default_Description) return Calendar is
+      X: Calendar:=
+        (Columns => 6, Rows => 2, Space_Between_Columns => 2,
+         Left_Space => 1,
+         Weekday_Rep =>  Des.Weekday_Rep,
+         Month_Rep   =>  Des.Month_Rep
+        );
+   begin
+      return X;
+   end Init_132;
+
+end Printable_Calendar;

Task/Calendar/Ada/calendar-3.ada

@@ -0,0 +1,11 @@
+with Printable_Calendar;
+
+procedure Cal is
+
+   C: Printable_Calendar.Calendar := Printable_Calendar.Init_80;
+
+begin
+   C.Print_Line_Centered("[reserved for Snoopy]");
+   C.New_Line;
+   C.Print(1969, "Nineteen-Sixty-Nine");
+end Cal;

Task/Calendar/Amazing-Hopper/calendar.hopper

@@ -0,0 +1,53 @@
+#include <jambo.h>
+
+Main
+   Set stack 15
+   año=0
+   Get arg numeric '2', Move to 'año'
+
+   Set '4,1,1,1' Init 'fila, columna, contador columna, contador mes)
+   meses={}
+   Let list ( meses := "Enero","Febrero","Marzo","Abril","Mayo",\
+                       "Junio","Julio","Agosto","Septiembre","Octubre",\
+                       "Noviembre","Diciembre" )
+   calendario=0
+   Let ( calendario := Calendar(1,año,12) )
+
+   Cls
+   Link gosub 'Cambia lenguaje de los meses, Imprime año'
+
+   Tok sep ("")
+   Gosub while ( i=1, Less(i,97), Dibuja calendario )
+End
+
+Subrutines
+
+Define 'Dibuja calendario'
+   Locate (fila, columna)  Just center (23, [ contador mes++ ] Cget 'meses')
+                           Print it
+   ++fila
+   Loc row (fila--)        [ {i}Plus(1):{i}Plus(7), 1:7 ] Cget 'calendario'
+                           Print this table
+   ++contador columna
+   columna += 25
+   When( Equals (contador columna, 4) ) {
+       Set '1', Copy to 'contador columna',
+                Move to 'columna'
+       fila+=9
+   }
+   i+=8
+Return
+
+Define 'Imprime año'
+   Locate (2,35),  Print (año)
+Return
+
+Define 'Cambia lenguaje de los meses'
+   Let ( calendario := Tran (" Do","Dom",calendario) )
+   Let ( calendario := Tran (" Lu","Lun",calendario) )
+   Let ( calendario := Tran (" Ma","Mar",calendario) )
+   Let ( calendario := Tran (" Mi","Mie",calendario) )
+   Let ( calendario := Tran (" Ju","Jue",calendario) )
+   Let ( calendario := Tran (" Vi","Vie",calendario) )
+   Let ( calendario := Tran (" Sa","Sab",calendario) )
+Return

Task/Calendar/AutoHotkey/calendar-1.ahk

@@ -0,0 +1,38 @@
+Calendar(Yr){
+	LastDay := [], Day := []
+	Titles =
+	(ltrim
+	______January_________________February_________________March_______
+	_______April____________________May____________________June________
+	________July___________________August_________________September_____
+	______October_________________November________________December______
+	)
+	StringSplit, title, titles, `n
+	Res := "________________________________" Yr "`r`n"
+
+	loop 4 {										; 4 Vertical Sections
+		Day[1]:=Yr SubStr("0" A_Index*3 -2, -1) 01
+		Day[2]:=Yr SubStr("0" A_Index*3 -1, -1) 01
+		Day[3]:=Yr SubStr("0" A_Index*3   , -1) 01
+		Res .= "`r`n" title%A_Index% "`r`nSu Mo Tu We Th Fr Sa    Su Mo Tu We Th Fr Sa    Su Mo Tu We Th Fr Sa"
+		loop , 6 {									; 6 Weeks max per month
+			Week := A_Index, Res .= "`r`n"
+			loop, 21 {								; 3 weeks times 7 days
+				Mon := Ceil(A_Index/7), ThisWD := Mod(A_Index-1,7)+1
+				FormatTime, WD, % Day[Mon], WDay
+				FormatTime, dd, % Day[Mon], dd
+				if (WD>ThisWD) {
+					Res .= "__ "
+					continue
+				}
+				dd := ((Week>3) && dd <10) ? "__" : dd, Res .= dd " ", LastDay[Mon] := Day[Mon], Day[Mon] +=1, Days
+				Res .= ((wd=7) && A_Index < 21) ? "___" : ""	
+				FormatTime, dd, % Day[Mon], dd
+			}
+		}
+		Res .= "`r`n"
+	}
+	StringReplace, Res, Res,_,%A_Space%, all
+	Res:=RegExReplace(Res,"`am)(^|\s)\K0", " ")
+	return res
+}

Task/Calendar/AutoHotkey/calendar-2.ahk

@@ -0,0 +1,15 @@
+Gui, font,s8, COURIER
+Gui, add, edit, vYr w40 r1 Limit4 Number, 1969
+Gui, add, edit, vEdit2 w580 r38
+Gui, Add, Button, Default Hidden gSubmit
+Gui, show
+
+Submit:
+Gui, Submit, NoHide
+GuiControl,, Edit2, % Calendar(Yr)
+return
+
+GuiEscape:
+GuiClose:
+ExitApp
+return

Task/Calendar/AutoIt/calendar.autoit

@@ -0,0 +1,102 @@
+#include <Date.au3>
+
+; Set the count of characters in each line, minimum is 20 - one month.
+Global $iPrintSize = 132
+
+; Set the count of months, you want to print side by side. With "0" it calculates automatically.
+; The number will corrected, if it not allowed to print in an rectangle.
+; If your print size is to small for given count, it will set back to automatically calculation.
+Global $iSideBySide = 3
+
+; Set the count of spaces between months.
+Global $iSpace = 4
+
+_CreateCalendar( 1969 )
+
+
+Func _CreateCalendar($_iYear)
+	Local $aMon[12] = ['       January      ', '      February      ', '        March       ', _
+	                   '        April       ', '         May        ', '        June        ', _
+	                   '        July        ', '       August       ', '      September     ', _
+	                   '       October      ', '      November      ', '      December      ']
+	Local $sHead = 'Mo Tu We Th Fr Sa Su'
+	Local $aDaysInMonth[12] = [31,28,31,30,31,30,31,31,30,31,30,31]
+	If _DateIsLeapYear($_iYear) Then $aDaysInMonth[1] = 29
+
+	; == assign date in weekday table for the whole year
+	Local $aAllDaysInMonth[6][7][12]   ; [ lines ][ weekdays ][ months ]
+	Local $iDay = 1, $iShift
+	For $i = 1 To 12
+		$iShift = _DateToDayOfWeekISO($_iYear, $i, 1) -1
+		For $j = 0 To 5
+			For $k = $iShift To 6
+				$aAllDaysInMonth[$j][$k][$i-1] = $iDay
+				$iDay += 1
+				If $iDay > $aDaysInMonth[$i-1] Then ExitLoop(2)
+			Next
+			$iShift = 0
+		Next
+		$iDay = 1
+	Next
+
+	; == check given side by side count, calculate if needed
+	If $iSideBySide > 0 Then
+		If $iPrintSize < ($iSideBySide *(20 +$iSpace) -$iSpace) Then $iSideBySide = 0
+	EndIf
+	Switch $iSideBySide
+		Case 0
+			$iSideBySide = Int($iPrintSize /(20 +$iSpace))
+			If $iPrintSize < 20 Then Return _PrintLine('Escape: Size Error')
+			If $iPrintSize < (20 +$iSpace) Then $iSideBySide = 1
+		Case 5
+			$iSideBySide = 4
+		Case 7 To 11
+			$iSideBySide = 6
+	EndSwitch
+
+	; == create space string
+	Local $sSpace = ''
+	For $i = 1 To $iSpace
+		$sSpace &= ' '
+	Next
+
+	; == print header
+	_PrintLine(@LF)
+	_PrintLine('[ here is Snoopy ]', @LF)
+	_PrintLine(StringRegExpReplace($_iYear, '(\d)(\d)(\d)(\d)', '$1 $2 $3 $4'), @LF)
+
+	; == create data for each line, in dependence to count of months in one line
+	Local $sLine, $iRight, $sTmp1, $sTmp2
+	For $n = 0 To 12 /$iSideBySide -1
+		$sTmp1 = ''
+		$sTmp2 = ''
+		For $z = 0 To $iSideBySide -1
+			$sTmp1 &= $aMon[$iSideBySide *$n+$z] & $sSpace
+			$sTmp2 &= $sHead & $sSpace
+		Next
+		_PrintLine(StringTrimRight($sTmp1, $iSpace))
+		_PrintLine(StringTrimRight($sTmp2, $iSpace))
+		For $j = 0 To 5
+			$sLine = ''
+			For $i = 1 To $iSideBySide
+				For $k = 0 To 6
+					$iRight = 3
+					If $k = 0 Then $iRight = 2
+					$sLine &= StringRight('   ' & $aAllDaysInMonth[$j][$k][$iSideBySide*$n+$i-1], $iRight)
+				Next
+				If $i < $iSideBySide Then $sLine &= $sSpace
+			Next
+			_PrintLine($sLine)
+		Next
+	Next
+EndFunc  ;==>_CreateCalendar
+
+Func _PrintLine($_sLine, $_sLF='')
+	Local $iLen = StringLen($_sLine)
+	Local $sSpace = '', $sLeft = ''
+	For $i = 1 To $iPrintSize-1
+		$sSpace &= ' '
+	Next
+	If $iLen < $iPrintSize Then $sLeft = StringLeft($sSpace, Int(($iPrintSize-$iLen)/2))
+	ConsoleWrite($sLeft & $_sLine & $_sLF & @LF)
+EndFunc  ;==>_PrintLine

Task/Calendar/BBC-BASIC/calendar.basic

@@ -0,0 +1,35 @@
+      INSTALL @lib$+"DATELIB"
+      VDU 23,22,640;570;8,15,16,128
+
+      year% = 1969
+      PRINT TAB(38); year%
+      DIM dom%(2), mjd%(2), dim%(2)
+
+      FOR day% = 1 TO 7
+        days$ += LEFT$(FN_date$(FN_mjd(day%, 1, 1905), "ddd"), 2) + " "
+      NEXT
+
+      FOR month% = 1 TO 10 STEP 3
+        PRINT
+        FOR col% = 0 TO 2
+          mjd%(col%) = FN_mjd(1, month% + col%, year%)
+          month$ = FN_date$(mjd%(col%), "MMMM")
+          PRINT TAB(col%*24 + 16 - LEN(month$)/2) month$;
+        NEXT
+        FOR col% = 0 TO 2
+          PRINT TAB(col%*24 + 6) days$;
+          dim%(col%) = FN_dim(month% + col%, year%)
+        NEXT
+        dom%() = 1
+        col% = 0
+        REPEAT
+          dow% = FN_dow(mjd%(col%))
+          IF dom%(col%)<=dim%(col%) THEN
+            PRINT TAB(col%*24 + dow%*3 + 6); dom%(col%);
+            dom%(col%) += 1
+            mjd%(col%) += 1
+          ENDIF
+          IF dow%=6 OR dom%(col%)>dim%(col%) col% = (col% + 1) MOD 3
+        UNTIL dom%(0)>dim%(0) AND dom%(1)>dim%(1) AND dom%(2)>dim%(2)
+        PRINT
+      NEXT

Task/Calendar/BaCon/calendar.bacon

@@ -0,0 +1,33 @@
+DECLARE month$[] = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" }
+DECLARE month[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
+year$ = "1969"
+' Leap year
+INCR month[1], IIF(MOD(VAL(year$), 4) = 0 OR MOD(VAL(year$), 100) = 0 AND MOD(VAL(year$), 400) <> 0, 1, 0)
+PRINT ALIGN$("[SNOOPY HERE]", 132, 2)
+PRINT ALIGN$(year$, 132, 2)
+FOR nr = 0 TO 11
+    row = 3
+    GOTOXY 1+(nr %6)*22, row+(nr/6)*9
+    PRINT ALIGN$(month$[nr], 21, 2);
+    INCR row
+    GOTOXY 1+(nr %6)*22, row+(nr/6)*9
+    PRINT ALIGN$("Mo Tu We Th Fr Sa Su", 21, 2);
+    INCR row
+    ' Each day
+    FOR day = 1 TO month[nr]
+        ' Zeller
+        J = VAL(LEFT$(year$, 2))
+        K = VAL(MID$(year$, 3, 2))
+        m = nr+1
+        IF nr < 2 THEN
+            INCR m, 12
+            DECR K
+        END IF
+        h = (day + ((m+1)*26)/10 + K + (K/4) + (J/4) + 5*J)
+        daynr = MOD(h, 7) - 2
+        IF daynr < 0 THEN INCR daynr, 7
+        IF daynr = 0 AND day > 1 THEN INCR row
+        GOTOXY 1+(nr %6)*22+daynr*3, row+(nr/6)*9
+        PRINT day;
+    NEXT
+NEXT

Task/Calendar/Batch-File/calendar.bat

@@ -0,0 +1,93 @@
+::Calender Task from Rosetta Code Wiki
+::Batch File Implementation
+
+@echo off
+setlocal enabledelayedexpansion
+
+	%== Set a valid year [will not be validated] ==%
+set y=1969
+
+	%== Set the variables for months (feb_l=the normal 28 days) ==%
+set jan_l=31&set apr_l=30
+set mar_l=31&set jun_l=30
+set may_l=31&set sep_l=30
+set jul_l=31&set nov_l=30
+set aug_l=31&set feb_l=28
+set oct_l=31
+set dec_l=31
+
+	%== Compute day for first day of the year ==%
+set /a d=(y/4+y)-(y/100-y/400)
+
+	%== Check if that year is a leap year ==%
+set /a "op1=y%%4","op2=y%%100","op3=y%%400"
+if not "%op1%"=="0" (goto :no_leap)
+if not "%op2%"=="0" (goto :yes_leap)
+if not "%op3%"=="0" (goto :no_leap)
+	:yes_leap
+		%== Ooops... Leap year. Change feb_l to 29. ==%
+		set feb_l=29
+		set/a d-=1
+	:no_leap
+
+	%== Compute weekday of the first day... ==%
+set /a d%%=7
+
+	%== Generate everything that's inside the calendar ==%
+for %%a in (jan feb mar apr may jun jul aug sep oct nov dec) do (
+	set %%a=
+	set chars_added=0
+	for /l %%b in (1,1,!d!) do (set "%%a=!%%a!   "&set /a chars_added+=3)
+	for /l %%c in (1,1,!%%a_l!) do (
+		if %%c lss 10 (set "%%a=!%%a! %%c ") else (set "%%a=!%%a!%%c ")
+		set /a chars_added+=3
+	)
+	for /l %%d in (!chars_added!,1,124) do set "%%a=!%%a! "
+	set /a d=^(d+%%a_l^)%%7
+)
+
+	%== Display the calendar ==%
+cls
+echo.
+echo.                              [SNOOPY]
+echo.
+echo. YEAR = %y%
+echo.
+echo.       January                February                March
+echo. Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa
+echo. %jan:~0,20%   %feb:~0,20%   %mar:~0,20%
+echo. %jan:~21,20%   %feb:~21,20%   %mar:~21,20%
+echo. %jan:~42,20%   %feb:~42,20%   %mar:~42,20%
+echo. %jan:~63,20%   %feb:~63,20%   %mar:~63,20%
+echo. %jan:~84,20%   %feb:~84,20%   %mar:~84,20%
+echo. %jan:~105%   %feb:~105%   %mar:~105%
+echo.
+echo.        April                   May                    June
+echo. Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa
+echo. %apr:~0,20%   %may:~0,20%   %jun:~0,20%
+echo. %apr:~21,20%   %may:~21,20%   %jun:~21,20%
+echo. %apr:~42,20%   %may:~42,20%   %jun:~42,20%
+echo. %apr:~63,20%   %may:~63,20%   %jun:~63,20%
+echo. %apr:~84,20%   %may:~84,20%   %jun:~84,20%
+echo. %apr:~105%   %may:~105%   %jun:~105%
+echo.
+echo.         July                  August                September
+echo. Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa
+echo. %jul:~0,20%   %aug:~0,20%   %sep:~0,20%
+echo. %jul:~21,20%   %aug:~21,20%   %sep:~21,20%
+echo. %jul:~42,20%   %aug:~42,20%   %sep:~42,20%
+echo. %jul:~63,20%   %aug:~63,20%   %sep:~63,20%
+echo. %jul:~84,20%   %aug:~84,20%   %sep:~84,20%
+echo. %jul:~105%   %aug:~105%   %sep:~105%
+echo.
+echo.       October                November               December
+echo. Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa
+echo. %oct:~0,20%   %nov:~0,20%   %dec:~0,20%
+echo. %oct:~21,20%   %nov:~21,20%   %dec:~21,20%
+echo. %oct:~42,20%   %nov:~42,20%   %dec:~42,20%
+echo. %oct:~63,20%   %nov:~63,20%   %dec:~63,20%
+echo. %oct:~84,20%   %nov:~84,20%   %dec:~84,20%
+echo. %oct:~105%   %nov:~105%   %dec:~105%
+echo.
+pause
+endlocal

Task/Calendar/Befunge/calendar.bf

@@ -0,0 +1,11 @@
+"P"00p&>:::4%!\"d"%*\45*:*%!+!!65*+31p:1-:::"I"5**\4/+\"d"/-\45*:*/+1+7%:0v
+J!F?M!A M!J J!A!S O!N D!SaFrThWeTuMoSuvp01:_1#!-#%:#\>#+6<v-2g1+1g01p1p01:<
+ January  February  March    April    >:45**00g\-\1-:v:<<6>+7%:10g2+:38*\`|
+   May      June     July    August v02-1:+4*-4\`\4:/_$:^^:/*2+92+2:g00$$$<
+September October  November December>p:45*+10g*\--2/00g4-2/>:#,1#*-#8\#4_$v
+>20g>:#,1#*-#8\#4_$6"$S" v. .vp040\$_4#!8#\*#-,#1>#:<+5g03g01:,,:+55<0.p03<
+^_v#:-1$_v#!:,*84,g1+1,< < ^ >::4%9*40g:8`!#v_$$$1+v^+g02_#v$#,$#+5<^_v#`\<
+-#8\#4_$7>1-:2*64*+:1g>^ ^   ^,g+2/4\+p04+1:<>1#\-#<:66+\^ >>$10g30g>:#,1#*
+> > $$55+,6>>40p:10g30g>:#,1#*-#8\#4_$>\:2*:1+1g2-50p1g640g-7*1+\-7v  v@,<6
+2:+g01$_55+,^ > > > > #^>#g>#0>#2_v v*2!!\%+55:\/+55:**`0\!`g05:::\<  >2-^^
+->:> >#^>#<>#<^#!:-1g04$$ < < < < < >4+8*+\:!!2*4+8*+,,48*,1+\1-:>#^_$$1+\1

Task/Calendar/C++/calendar.cpp

@@ -0,0 +1,156 @@
+#include <windows.h>
+#include <iostream>
+
+//--------------------------------------------------------------------------------------------------
+using namespace std;
+
+
+//--------------------------------------------------------------------------------------------------
+class calender
+{
+public:
+    void drawCalender( int y )
+    {
+	year = y;
+	for( int i = 0; i < 12; i++ )
+	    firstdays[i] = getfirstday( i );
+
+	isleapyear();
+	build();
+    }
+
+private:
+    void isleapyear()
+    {
+	isleap = false;
+
+	if( !( year % 4 ) )
+	{
+	    if( year % 100 ) isleap = true;
+	    else if( !( year % 400 ) ) isleap = true;
+	}
+    }
+
+    int getfirstday( int m )
+    {
+	int y = year;
+
+	int f = y + 1 + 3 * m - 1;
+	m++;
+	if( m < 3 ) y--;
+	else f -= int( .4 * m + 2.3 );
+
+	f += int( y / 4 ) - int( ( y / 100 + 1 ) * 0.75 );
+	f %= 7;
+
+	return f;
+    }
+
+    void build()
+    {
+	int days[] = { 31, isleap ? 29 : 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
+	int lc = 0, lco = 0, ystr = 7, start = 2, fd = 0, m = 0;
+	HANDLE h = GetStdHandle( STD_OUTPUT_HANDLE );
+	COORD pos = { 0, ystr };
+	draw();
+
+	for( int i = 0; i < 4; i++ )
+	{
+	    for( int j = 0; j < 3; j++ )
+	    {
+		int d = firstdays[fd++], dm = days[m++];
+		pos.X = d * 3 + start;
+		SetConsoleCursorPosition( h, pos );
+
+		for( int dd = 0; dd < dm; dd++ )
+		{
+		    if( dd < 9 ) cout << 0 << dd + 1 << " ";
+		    else cout << dd + 1 << " ";
+
+		    pos.X += 3;
+		    if( pos.X - start > 20 )
+		    {
+			pos.X = start; pos.Y++;
+			SetConsoleCursorPosition( h, pos );
+		    }
+		}
+
+		start += 23;
+		pos.X = start; pos.Y = ystr;
+		SetConsoleCursorPosition( h, pos );
+	    }
+	    ystr += 9; start = 2;
+	    pos.Y = ystr;
+	}
+    }
+
+    void draw()
+    {
+	system( "cls" );
+	cout << "+--------------------------------------------------------------------+" << endl;
+	cout << "|                              [SNOOPY]                              |" << endl;
+	cout << "|                                                                    |" << endl;
+	cout << "|                             == " << year << " ==                             |" << endl;
+	cout << "+----------------------+----------------------+----------------------+" << endl;
+	cout << "|       JANUARY        |       FEBRUARY       |         MARCH        |" << endl;
+	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "+----------------------+----------------------+----------------------+" << endl;
+	cout << "|        APRIL         |          MAY         |         JUNE         |" << endl;
+	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "+----------------------+----------------------+----------------------+" << endl;
+	cout << "|         JULY         |        AUGUST        |       SEPTEMBER      |" << endl;
+	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "+----------------------+----------------------+----------------------+" << endl;
+	cout << "|        OCTOBER       |       NOVEMBER       |       DECEMBER       |" << endl;
+	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "|                      |                      |                      |" << endl;
+	cout << "+----------------------+----------------------+----------------------+" << endl;
+    }
+
+    int firstdays[12], year;
+    bool isleap;
+};
+//--------------------------------------------------------------------------------------------------
+int main( int argc, char* argv[] )
+{
+    int y;
+    calender cal;
+
+    while( true )
+    {
+	system( "cls" );
+	cout << "Enter the year( yyyy ) --- ( 0 to quit ): ";
+	cin >> y;
+	if( !y ) return 0;
+
+	cal.drawCalender( y );
+	cout << endl << endl << endl << endl << endl << endl << endl << endl;
+
+	system( "pause" );
+    }
+    return 0;
+}
+//--------------------------------------------------------------------------------------------------

Task/Calendar/C-sharp/calendar.cs

@@ -0,0 +1,90 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace CalendarStuff
+{
+
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WindowHeight = 46;
+            Console.Write(buildMonths(new DateTime(1969, 1, 1)));
+            Console.Read();
+        }
+        private static string buildMonths(DateTime date)
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.AppendLine(center("[Snoop]", 24 * 3));
+            sb.AppendLine();
+            sb.AppendLine(center(date.Year.ToString(), 24 * 3));
+
+            List<DateTime> dts = new List<DateTime>();
+            while (true)
+            {
+                dts.Add(date);
+                if (date.Year != ((date = date.AddMonths(1)).Year))
+                {
+                    break;
+                }
+            }
+            var jd = dts.Select(a => buildMonth(a).GetEnumerator()).ToArray();
+
+            int sCur=0;
+            while (sCur<dts.Count)
+            {
+                sb.AppendLine();
+                int curMonth=0;
+                var j = jd.Where(a => curMonth++ >= sCur && curMonth - 1 < sCur + 3).ToArray(); //grab the next 3
+                sCur += j.Length;
+                bool breakOut = false;
+                while (!breakOut)
+                {
+                    int inj = 1;
+                    foreach (var cd in j)
+                    {
+                        if (cd.MoveNext())
+                        {
+                            sb.Append((cd.Current.Length == 21 ? cd.Current : cd.Current.PadRight(21, ' ')) + "     ");
+                        }
+                        else
+                        {
+                            sb.Append("".PadRight(21, ' ') + "     ");
+                            breakOut = true;
+                        }
+                        if (inj++ % 3 == 0) sb.AppendLine();
+                    }
+                }
+
+            }
+            return sb.ToString();
+        }
+
+
+        private static IEnumerable<string> buildMonth(DateTime date)
+        {
+            yield return center(date.ToString("MMMM"),7*3);
+            var j = DateTime.DaysInMonth(date.Year, date.Month);
+            yield return Enum.GetNames(typeof(DayOfWeek)).Aggregate("", (current, result) => current + (result.Substring(0, 2).ToUpper() + " "));
+            string cur = "";
+            int total = 0;
+
+            foreach (var day in Enumerable.Range(-((int)date.DayOfWeek),j + (int)date.DayOfWeek))
+            {
+                cur += (day < 0 ? "  " : ((day < 9 ? " " : "") + (day + 1))) +" ";
+                if (total++ > 0 && (total ) % 7 == 0)
+                {
+                    yield return cur;
+                    cur = "";
+                }
+            }
+            yield return cur;
+        }
+        private static string center(string s, int len)
+        {
+            return (s.PadLeft((len - s.Length) / 2 + s.Length, ' ').PadRight((len), ' '));
+        }
+    }
+}

Task/Calendar/C/calendar-1.c

@@ -0,0 +1,125 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+int width = 80, year = 1969;
+int cols, lead, gap;
+
+const char *wdays[] = { "Su", "Mo", "Tu", "We", "Th", "Fr", "Sa" };
+struct months {
+	const char *name;
+	int days, start_wday, at;
+} months[12] = {
+	{ "January",	31, 0, 0 },
+	{ "February",	28, 0, 0 },
+	{ "March",	31, 0, 0 },
+	{ "April",	30, 0, 0 },
+	{ "May",	31, 0, 0 },
+	{ "June",	30, 0, 0 },
+	{ "July",	31, 0, 0 },
+	{ "August",	31, 0, 0 },
+	{ "September",	30, 0, 0 },
+	{ "October",	31, 0, 0 },
+	{ "November",	30, 0, 0 },
+	{ "December",	31, 0, 0 }
+};
+
+void space(int n) { while (n-- > 0) putchar(' '); }
+
+void init_months()
+{
+	int i;
+
+	if ((!(year % 4) && (year % 100)) || !(year % 400))
+		months[1].days = 29;
+
+	year--;
+	months[0].start_wday
+		= (year * 365 + year/4 - year/100 + year/400 + 1) % 7;
+
+	for (i = 1; i < 12; i++)
+		months[i].start_wday =
+			(months[i-1].start_wday + months[i-1].days) % 7;
+
+	cols = (width + 2) / 22;
+	while (12 % cols) cols--;
+	gap = cols - 1 ? (width - 20 * cols) / (cols - 1) : 0;
+	if (gap > 4) gap = 4;
+	lead = (width - (20 + gap) * cols + gap + 1) / 2;
+        year++;
+}
+
+void print_row(int row)
+{
+	int c, i, from = row * cols, to = from + cols;
+	space(lead);
+	for (c = from; c < to; c++) {
+		i = strlen(months[c].name);
+		space((20 - i)/2);
+		printf("%s", months[c].name);
+		space(20 - i - (20 - i)/2 + ((c == to - 1) ? 0 : gap));
+	}
+	putchar('\n');
+
+	space(lead);
+	for (c = from; c < to; c++) {
+		for (i = 0; i < 7; i++)
+			printf("%s%s", wdays[i], i == 6 ? "" : " ");
+		if (c < to - 1) space(gap);
+		else putchar('\n');
+	}
+
+	while (1) {
+		for (c = from; c < to; c++)
+			if (months[c].at < months[c].days) break;
+		if (c == to) break;
+
+		space(lead);
+		for (c = from; c < to; c++) {
+			for (i = 0; i < months[c].start_wday; i++) space(3);
+			while(i++ < 7 && months[c].at < months[c].days) {
+				printf("%2d", ++months[c].at);
+				if (i < 7 || c < to - 1) putchar(' ');
+			}
+			while (i++ <= 7 && c < to - 1) space(3);
+			if (c < to - 1) space(gap - 1);
+			months[c].start_wday = 0;
+		}
+		putchar('\n');
+	}
+	putchar('\n');
+}
+
+void print_year()
+{
+	int row;
+	char buf[32];
+	sprintf(buf, "%d", year);
+	space((width - strlen(buf)) / 2);
+	printf("%s\n\n", buf);
+	for (row = 0; row * cols < 12; row++)
+		print_row(row);
+}
+
+int main(int c, char **v)
+{
+	int i, year_set = 0;
+	for (i = 1; i < c; i++) {
+		if (!strcmp(v[i], "-w")) {
+			if (++i == c || (width = atoi(v[i])) < 20)
+				goto bail;
+		} else if (!year_set) {
+			if (!sscanf(v[i], "%d", &year) || year <= 0)
+				year = 1969;
+			year_set = 1;
+		} else
+			goto bail;
+	}
+
+	init_months();
+	print_year();
+	return 0;
+
+bail:	fprintf(stderr, "bad args\nUsage: %s year [-w width (>= 20)]\n", v[0]);
+	exit(1);
+}

Task/Calendar/C/calendar-2.c

@@ -0,0 +1,79 @@
+#include <gadget/gadget.h>
+LIB_GADGET_START
+
+void draw_calendar( RDS(char*,calendario), int year );
+void print_calendar( RDS(char*,calendario) );
+
+Main
+
+   Assert( Arg_count ==2, fail_arg );
+   Get_arg_int( year, 1 );
+
+   ACTUAL_LANG_DATE = EN; /* text in english */
+
+   New array calendario as string;
+   /* get full year:
+      112 = code for months after initial month.
+      1 = initial month
+      year = well... */
+   calendario = Calendar(calendario, 112, 1, year);
+
+   draw_calendar( SDS(calendario), year );
+
+   Free str array calendario;
+
+   Exception( fail_arg ){
+       Msg_yellow("Modo de uso:\n  ./calendar <nYear>");
+   }
+
+End
+
+void draw_calendar( RDS( char*, calendario), int year )
+{
+   int fila=4, columna=1, cnt_columna=1, cnt_mes=0, i=0;
+
+   Cls;
+   At 2,35;  Print "%d", year;
+
+   while ( cnt_mes < 12 )
+   {
+      String month_name;
+      Stack {
+          Store ( month_name, Pad_c( Capital( Get_monthname(cnt_mes++) ),' ',23) );
+      } Stack_off;
+
+      At fila, columna;  Print "%s", month_name;
+
+      Atrow ++fila;
+
+      Range for calendario [ i+1: 1: i+8, 0:1: Cols(calendario) ];
+      print_calendar( SDS(calendario) );
+      --fila;
+
+      ++cnt_columna;
+      columna += 25;
+      When( cnt_columna == 4 ) {
+          cnt_columna = columna = 1;
+          fila+=9;
+      }
+      i+=8;
+      Free secure month_name;
+   }
+   Prnl;
+}
+
+
+void print_calendar( RDS(char*,calendario) )
+{
+   int i,j;
+   int row = SCREEN_ROW;
+
+   Iterup( row, calendario, i)
+   {
+       Iterup( col, calendario, j)
+       {
+            Print "%*s", 3, $calendario[i,j];
+       }
+       Atrow ++row;
+   }
+}

Task/Calendar/COBOL/calendar.cobol

@@ -0,0 +1,226 @@
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID.  CALEND.
+       ENVIRONMENT DIVISION.
+       INPUT-OUTPUT SECTION.
+       DATA DIVISION.
+
+       WORKING-STORAGE SECTION.
+       01  WS-DAY-NAMES-DEF.
+         03 FILLER PIC X(09) VALUE 'SUNDAY   '.
+         03 FILLER PIC X(09) VALUE 'MONDAY   '.
+         03 FILLER PIC X(09) VALUE 'TUESDAY  '.
+         03 FILLER PIC X(09) VALUE 'WEDNESDAY'.
+         03 FILLER PIC X(09) VALUE 'THURSDAY '.
+         03 FILLER PIC X(09) VALUE 'FRIDAY   '.
+         03 FILLER PIC X(09) VALUE 'SATURDAY '.
+       01  FILLER REDEFINES WS-DAY-NAMES-DEF.
+         03  WS-DAY-NAME       PIC X(09) OCCURS 07 TIMES.
+
+       01  WS-MTH-INFO-DEF.
+         03 FILLER PIC X(11) VALUE 'JANUARY  31'.
+         03 FILLER PIC X(11) VALUE 'FEBRUARY 28'.
+         03 FILLER PIC X(11) VALUE 'MARCH    31'.
+         03 FILLER PIC X(11) VALUE 'APRIL    30'.
+         03 FILLER PIC X(11) VALUE 'MAY      31'.
+         03 FILLER PIC X(11) VALUE 'JUNE     30'.
+         03 FILLER PIC X(11) VALUE 'JULY     31'.
+         03 FILLER PIC X(11) VALUE 'AUGUST   31'.
+         03 FILLER PIC X(11) VALUE 'SEPTEMBER30'.
+         03 FILLER PIC X(11) VALUE 'OCTOBER  31'.
+         03 FILLER PIC X(11) VALUE 'NOVEMBER 30'.
+         03 FILLER PIC X(11) VALUE 'DECEMBER 31'.
+       01  FILLER REDEFINES WS-MTH-INFO-DEF.
+         03  WS-MTH-INFO-TABLE OCCURS 12 TIMES.
+           05  WS-MTH-INFO-NAME   PIC X(09).
+           05  WS-MTH-INFO-DAYS   PIC 9(02).
+
+       01  WS-MTH-AREA.
+         03  WS-MTH-DD         PIC S99.
+         03  WS-DAY1           PIC   9.
+         03  WS-DAYS           PIC  99.
+         03  WS-DD             PIC   9.
+         03  WS-WK             PIC   9.
+         03  WS-MM             PIC  99.
+         03  WS-QQ             PIC  99.
+
+         03  WS-MTH-MONTH  OCCURS 12 TIMES.
+           05  WS-MTH-WEEK OCCURS 6 TIMES.
+             07  WS-DAY-FLD      OCCURS 7 TIMES.
+               09  WS-DAY        PIC ZZ.
+       01  INPDATE-RECORD.
+           05  INPD-YEAR          PIC 9(04).
+           05  FILLER             PIC X(01).
+           05  INPD-MONTH         PIC 9(02).
+           05  FILLER             PIC X(01).
+           05  INPD-DAY           PIC 9(02).
+       01  WMS-DOW                PIC 9(01).
+       01  WS-PRT                 PIC X(132).
+       01  WS-COL                 PIC  9(03) VALUE 0.
+       01  WS-PP                  PIC  9(03) VALUE 0.
+       01  WS-CFGN.
+         03  FILLER               PIC  9(03) VALUE  80.
+         03  FILLER               PIC  9(02) VALUE  5.
+         03  FILLER               PIC  9(01) VALUE  1.
+         03  FILLER               PIC  9(02) VALUE  5.
+         03  FILLER               PIC  9(01) VALUE  2.
+       01  WS-CFGW.
+         03  FILLER               PIC  9(03) VALUE 120.
+         03  FILLER               PIC  9(02) VALUE 10.
+         03  FILLER               PIC  9(01) VALUE  2.
+         03  FILLER               PIC  9(02) VALUE 10.
+         03  FILLER               PIC  9(01) VALUE  3.
+       01  WS-CFG.
+         03  WS-LS                PIC  9(03) VALUE 120.
+         03  WS-LMAR              PIC  9(02) VALUE 10.
+         03  WS-SPBD              PIC  9(01) VALUE  2.
+         03  WS-SPBC              PIC  9(02) VALUE 10.
+         03  WS-DNMW              PIC  9(01) VALUE  3.
+       PROCEDURE DIVISION.
+           MOVE '1969-01-01' TO INPDATE-RECORD
+           MOVE WS-CFGN   TO WS-CFG
+           IF  (FUNCTION MOD ( INPD-YEAR , 400 ) = 0
+           OR  (FUNCTION MOD ( INPD-YEAR , 4   ) = 0
+               AND
+               FUNCTION MOD ( INPD-YEAR , 100 ) NOT = 0))
+             MOVE 29         TO WS-MTH-INFO-DAYS (02)
+           ELSE
+             MOVE 28         TO WS-MTH-INFO-DAYS (02)
+           END-IF
+
+           PERFORM VARYING WS-MM FROM 1 BY +1
+           UNTIL WS-MM > 12
+           MOVE WS-MM TO INPD-MONTH
+           CALL 'DATE2DOW' USING INPDATE-RECORD, WMS-DOW
+           COMPUTE WS-MTH-DD = 1 - WMS-DOW
+           COMPUTE WS-DAYS = WS-MTH-INFO-DAYS (INPD-MONTH)
+           PERFORM VARYING WS-WK FROM 1 BY +1
+           UNTIL WS-WK > 6
+             PERFORM VARYING WS-DD FROM 1 BY +1
+             UNTIL WS-DD > 7
+               COMPUTE WS-MTH-DD = WS-MTH-DD + 1
+               IF (WS-MTH-DD < 1)
+               OR (WS-MTH-DD > WS-DAYS)
+                 MOVE 0         TO WS-DAY (WS-MM, WS-WK, WS-DD)
+               ELSE
+                 MOVE WS-MTH-DD TO WS-DAY (WS-MM, WS-WK, WS-DD)
+               END-IF
+             END-PERFORM
+           END-PERFORM
+           END-PERFORM
+
+           COMPUTE WS-MM = 0
+           PERFORM VARYING WS-QQ FROM 1 BY +1
+           UNTIL WS-QQ > 4
+
+             INITIALIZE WS-PRT
+             COMPUTE WS-PP = 1
+             PERFORM VARYING WS-COL FROM 1 BY +1
+             UNTIL WS-COL > 3
+             COMPUTE WS-MM = 3 * (WS-QQ - 1) + WS-COL
+
+               IF WS-COL = 1
+                 COMPUTE WS-PP = WS-PP + WS-LMAR + 2 - WS-DNMW
+               ELSE
+                 COMPUTE WS-PP = WS-PP + WS-SPBC + 2 - WS-DNMW
+               END-IF
+               MOVE WS-MTH-INFO-NAME (WS-MM)
+                             TO WS-PRT(WS-PP:9)
+               COMPUTE WS-PP
+               =       WS-PP + ( 2 * 7 + WS-SPBD * 6 + WS-SPBD - 1)
+               -       4
+               MOVE INPD-YEAR TO WS-PRT (WS-PP:4)
+               COMPUTE WS-PP = WS-PP + 4
+             END-PERFORM
+             DISPLAY WS-PRT (1:WS-LS)
+
+             INITIALIZE WS-PRT
+             COMPUTE WS-PP = 1
+             PERFORM VARYING WS-COL FROM 1 BY +1
+             UNTIL WS-COL > 3
+             COMPUTE WS-MM = 3 * (WS-QQ - 1) + WS-COL
+
+               IF WS-COL = 1
+                 COMPUTE WS-PP = WS-PP + WS-LMAR + 2 - WS-DNMW
+               ELSE
+                 COMPUTE WS-PP = WS-PP + WS-SPBC + 2 - WS-DNMW
+               END-IF
+               PERFORM VARYING WS-DD FROM 1 BY +1
+               UNTIL WS-DD > 7
+                 IF WS-DD > 1
+                   COMPUTE WS-PP = WS-PP + WS-SPBD + 2 - WS-DNMW
+                 END-IF
+                 MOVE WS-DAY-NAME (WS-DD) (1:WS-DNMW)
+                             TO WS-PRT (WS-PP:WS-DNMW)
+                 COMPUTE WS-PP = WS-PP + WS-DNMW
+               END-PERFORM
+             END-PERFORM
+             DISPLAY WS-PRT (1:WS-LS)
+
+             PERFORM VARYING WS-WK FROM 1 BY +1
+             UNTIL WS-WK > 6
+               INITIALIZE WS-PRT
+               COMPUTE WS-PP = 1
+               PERFORM VARYING WS-COL FROM 1 BY +1
+               UNTIL WS-COL > 3
+               COMPUTE WS-MM = 3 * (WS-QQ - 1) + WS-COL
+
+                 IF WS-COL = 1
+                   COMPUTE WS-PP = WS-PP + WS-LMAR
+                 ELSE
+                   COMPUTE WS-PP = WS-PP + WS-SPBC
+                 END-IF
+                 PERFORM VARYING WS-DD FROM 1 BY +1
+                 UNTIL WS-DD > 7
+                   IF WS-DD > 1
+                     COMPUTE WS-PP = WS-PP + WS-SPBD
+                   END-IF
+                   MOVE WS-DAY (WS-MM, WS-WK, WS-DD)
+                               TO WS-PRT (WS-PP:2)
+                   COMPUTE WS-PP = WS-PP + 2
+                 END-PERFORM
+               END-PERFORM
+               DISPLAY WS-PRT (1:WS-LS)
+             END-PERFORM
+             DISPLAY ' '
+           END-PERFORM
+           GOBACK
+           .
+       END PROGRAM CALEND.
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID.  DATE2DOW.
+       ENVIRONMENT DIVISION.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01  WMS-WORK-AREA.
+         03  WMS-YEAR       PIC 9(04).
+         03  WMS-MONTH      PIC 9(02).
+         03  WMS-CSYS       PIC 9(01) VALUE 1.
+         03  WMS-SUM        pic 9(04).
+       LINKAGE SECTION.
+       01  INPDATE-RECORD.
+           05  INPD-YEAR          PIC 9(04).
+           05  FILLER             PIC X(01).
+           05  INPD-MONTH         PIC 9(02).
+           05  FILLER             PIC X(01).
+           05  INPD-DAY           PIC 9(02).
+       01  WMS-DOW                PIC 9(01).
+       PROCEDURE DIVISION USING INPDATE-RECORD, WMS-DOW.
+       1010-CONVERT-DATE-TO-DOW.
+           IF INPD-MONTH < 3
+               COMPUTE WMS-MONTH = INPD-MONTH + 12
+               COMPUTE WMS-YEAR  = INPD-YEAR - 1
+           ELSE
+               COMPUTE WMS-MONTH = INPD-MONTH
+               COMPUTE WMS-YEAR  = INPD-YEAR
+           END-IF
+           COMPUTE WMS-SUM  =
+                            ( INPD-DAY + 2 * WMS-MONTH + WMS-YEAR
+                            + FUNCTION INTEGER (6 * (WMS-MONTH + 1) / 10)
+                            + FUNCTION INTEGER ( WMS-YEAR / 4   )
+                            - FUNCTION INTEGER ( WMS-YEAR / 100 )
+                            + FUNCTION INTEGER ( WMS-YEAR / 400 )
+                            + WMS-CSYS )
+           COMPUTE WMS-DOW = FUNCTION MOD (WMS-SUM, 7) + 1
+           GOBACK
+           .
+       END PROGRAM DATE2DOW.

Task/Calendar/Clojure/calendar.clj

@@ -0,0 +1,126 @@
+(require '[clojure.string :only [join] :refer [join]])
+
+(def day-row "Su Mo Tu We Th Fr Sa")
+
+(def col-width (count day-row))
+
+(defn month-to-word
+  "Translate a month from 0 to 11 into its word representation."
+  [month]
+  ((vec (.getMonths (new java.text.DateFormatSymbols))) month))
+
+(defn month [date]
+  (.get date (java.util.Calendar/MONTH)))
+
+(defn total-days-in-month [date]
+  (.getActualMaximum date (java.util.Calendar/DAY_OF_MONTH)))
+
+(defn first-weekday [date]
+  (.get date (java.util.Calendar/DAY_OF_WEEK)))
+
+(defn normal-date-string
+  "Returns a formatted list of strings of the days of the month."
+  [date]		
+  (map #(join " " %)
+    (partition 7
+      (concat
+        (repeat (dec (first-weekday date)) "  ")
+        (map #(format "%2s" %)
+               (range 1 (inc (total-days-in-month date))))
+        (repeat (- 42 (total-days-in-month date)
+                      (dec (first-weekday date)) ) "  ")))))
+
+		
+(defn oct-1582-string
+  "Returns a formatted list of strings of the days of the month of October 1582."
+  [date]
+  (map #(join " " %)
+    (partition 7
+      (concat
+         (repeat (dec (first-weekday date)) "  ")
+         (map #(format "%2s" %)
+                 (concat (range 1 5)
+                         (range 15 (inc (total-days-in-month date)))))
+         (repeat (- 42
+                    (count (concat (range 1 5)
+		                   (range 15
+                                          (inc (total-days-in-month date)))))
+                    (dec (first-weekday date)) ) "  ")))))
+
+
+(defn center-string
+  "Returns a string that is WIDTH long with STRING centered in it."
+  [string width]
+  (let [pad (- width (count string))
+        lpad (quot pad 2)
+        rpad (- pad (quot pad 2))]
+    (if (<= pad 0)
+    string
+    (str (apply str (repeat lpad " "))  ; remove vector
+          string
+         (apply str (repeat rpad " "))))))
+
+
+(defn calc-columns
+  "Calculates the number of columns given the width in CHARACTERS and the
+   MARGIN SIZE."
+  [characters margin-size]
+  (loop [cols 0 excess  characters ]
+    (if (>= excess  col-width)
+        (recur (inc cols) (- excess (+ margin-size col-width)))
+         cols)))
+
+(defn month-vector
+  "Returns a vector with the month name, day-row and days
+   formatted for printing."
+  [date]
+  (vec (concat
+         (vector (center-string (month-to-word (month date)) col-width))
+         (vector day-row)
+ 		 (if (and (= 1582 (.get date (java.util.Calendar/YEAR)))
+		 		  (= 9 (month date)))
+		     (oct-1582-string date)
+                     (normal-date-string date)))))
+
+(defn year-vector [date]
+  "Returns a 2d vector of all the months in the year of DATE."
+  (loop [m [] c (month date)]
+    (if (= c 11 )
+        (conj m (month-vector date))
+        (recur (conj m (month-vector date))
+               (do (.add date (java.util.Calendar/MONTH ) 1)
+                   (month date))))))
+
+(defn print-months
+  "Prints the months to standard output with NCOLS and MARGIN."
+  [ v ncols margin]
+  (doseq [r (range (Math/ceil (/ 12 ncols)))]
+    (do (doseq [i (range 8)]
+          (do (doseq [c (range (* r ncols) (* (+ r 1) ncols))
+		                :while (< c 12)]
+              (printf (str (apply str (repeat margin " ")) "%s")
+		      (get-in v [c i])))
+          (println)))
+        (println))))
+
+(defn print-cal
+  "(print-cal [year [width [margin]]])
+   Prints out the calendar for a given YEAR with WIDTH characters wide and
+   with MARGIN spaces between months."
+  ([]
+     (print-cal 1969 80 2))
+  ([year]
+     (print-cal year 80 2))
+  ([year width]
+   (print-cal year width 2))
+  ([year width margin]
+     (assert (>= width (count day-row)) "Width should be more than 20.")
+     (assert (> margin 0) "Margin needs to be more than 0.")
+     (let [date (new java.util.GregorianCalendar year 0 1)
+           column-count (calc-columns width margin)
+           total-size (+ (* column-count (count day-row))
+                         (* (dec column-count) margin))]
+       (println (center-string "[Snoopy Picture]" total-size))
+       (println (center-string (str year) total-size))
+       (println)
+       (print-months (year-vector date) column-count margin))))

Task/Calendar/Common-Lisp/calendar.lisp

@@ -0,0 +1,75 @@
+(ql:quickload '(date-calc))
+
+(defparameter *day-row* "Su Mo Tu We Th Fr Sa")
+(defparameter *calendar-margin* 3)
+
+(defun month-to-word (month)
+  "Translate a MONTH from 1 to 12 into its word representation."
+  (svref #("January" "February" "March" "April"
+           "May" "June" "July" "August"
+           "September" "October" "November" "December")
+         (1- month)))
+
+(defun month-strings (year month)
+  "Collect all of the strings that make up a calendar for a given
+MONTH and YEAR."
+  `(,(date-calc:center (month-to-word month) (length *day-row*))
+     ,*day-row*
+     ;; We can assume that a month calendar will always fit into a 7 by 6 block
+     ;; of values. This makes it easy to format the resulting strings.
+     ,@ (let ((days (make-array (* 7 6) :initial-element nil)))
+          (loop :for i :from (date-calc:day-of-week year month 1)
+             :for day :from 1 :to (date-calc:days-in-month year month)
+             :do (setf (aref days i) day))
+          (loop :for i :from 0 :to 5
+             :collect
+             (format nil "~{~:[  ~;~2,d~]~^ ~}"
+                     (loop :for day :across (subseq days (* i 7) (+ 7 (* i 7)))
+                        :append (if day (list day day) (list day))))))))
+
+(defun calc-columns (characters margin-size)
+  "Calculate the number of columns given the number of CHARACTERS per
+column and the MARGIN-SIZE between them."
+  (multiple-value-bind (cols excess)
+      (truncate characters (+ margin-size (length *day-row*)))
+    (incf excess margin-size)
+    (if (>= excess (length *day-row*))
+        (1+ cols)
+        cols)))
+
+(defun take (n list)
+  "Take the first N elements of a LIST."
+  (loop :repeat n :for x :in list :collect x))
+
+(defun drop (n list)
+  "Drop the first N elements of a LIST."
+  (cond ((or (<= n 0) (null list)) list)
+        (t (drop (1- n) (cdr list)))))
+
+(defun chunks-of (n list)
+  "Split the LIST into chunks of size N."
+  (assert (> n 0))
+  (loop :for x := list :then (drop n x)
+     :while x
+     :collect (take n x)))
+
+(defun print-calendar (year &key (characters 80) (margin-size 3))
+  "Print out the calendar for a given YEAR, optionally specifying
+a width limit in CHARACTERS and MARGIN-SIZE between months."
+  (assert (>= characters (length *day-row*)))
+  (assert (>= margin-size 0))
+  (let* ((calendars (loop :for month :from 1 :to 12
+                       :collect (month-strings year month)))
+         (column-count (calc-columns characters margin-size))
+         (total-size (+ (* column-count (length *day-row*))
+                        (* (1- column-count) margin-size)))
+         (format-string (concatenate 'string
+                                     "~{~a~^~" (write-to-string margin-size) ",0@T~}~%")))
+    (format t "~a~%~a~%~%"
+            (date-calc:center "[Snoopy]" total-size)
+            (date-calc:center (write-to-string year) total-size))
+    (loop :for row :in (chunks-of column-count calendars)
+       :do (apply 'mapcar
+                  (lambda (&rest heads)
+                    (format t format-string heads))
+                  row))))

Task/Calendar/D/calendar.d

@@ -0,0 +1,43 @@
+import std.stdio, std.datetime, std.string, std.conv;
+
+void printCalendar(in uint year, in uint nCols)
+in {
+    assert(nCols > 0 && nCols <= 12);
+} body {
+    immutable rows = 12 / nCols + (12 % nCols != 0);
+    auto date = Date(year, 1, 1);
+    int offs = date.dayOfWeek;
+    const months = "January February March April May June
+        July August September October November December".split;
+
+    string[8][12] mons;
+    foreach (immutable m; 0 .. 12) {
+        mons[m][0] = months[m].center(21);
+        mons[m][1] = " Su Mo Tu We Th Fr Sa";
+        immutable dim = date.daysInMonth;
+        foreach (immutable d; 1 .. 43) {
+            immutable day = d > offs && d <= offs + dim;
+            immutable str = day ? format(" %2s", d-offs) : "   ";
+            mons[m][2 + (d - 1) / 7] ~= str;
+        }
+        offs = (offs + dim) % 7;
+        date.add!"months"(1);
+    }
+
+    "[Snoopy Picture]".center(nCols * 24 + 4).writeln;
+    writeln(year.text.center(nCols * 24 + 4), "\n");
+    foreach (immutable r; 0 .. rows) {
+        string[8] s;
+        foreach (immutable c; 0 .. nCols) {
+            if (r * nCols + c > 11)
+                break;
+            foreach (immutable i, line; mons[r * nCols + c])
+                s[i] ~= format("   %s", line);
+        }
+        writefln("%-(%s\n%)\n", s);
+    }
+}
+
+void main() {
+    printCalendar(1969, 3);
+}

Task/Calendar/Delphi/calendar.delphi

@@ -0,0 +1,89 @@
+program Calendar;
+
+{$APPTYPE CONSOLE}
+
+uses
+  System.SysUtils,
+  System.DateUtils;
+
+function Center(s: string; width: Integer): string;
+var
+  side: Integer;
+begin
+  if s.Length >= width then
+    exit(s);
+  side := (width - s.Length) div 2;
+  Result := s + string.Create(' ', side);
+  Result := string.Create(' ', width - Result.Length) + Result;
+end;
+
+procedure PrintCalendar(year, nCols: word; local: string = 'en-US');
+var
+  fmt: TFormatSettings;
+begin
+  if (nCols <= 0) or (nCols > 12) then
+    exit;
+  fmt := TFormatSettings.Create(local);
+  var rows := 12 div nCols + ord(12 mod nCols <> 0);
+  var date := EncodeDate(year, 1, 1);
+  var offs := DayOfTheWeek(date);
+
+  var months: TArray<string>;
+  setlength(months, 12);
+  for var i := 1 to 12 do
+    months[i - 1] := fmt.LongMonthNames[i];
+
+  var sWeek := '';
+  for var i := 1 to 7 do
+    sWeek := sWeek + ' ' + copy(fmt.ShortDayNames[i], 1, 2);
+
+  var mons: TArray<TArray<string>>;
+  SetLength(mons, 12, 8);
+  for var m := 0 to 11 do
+  begin
+    mons[m, 0] := Center(months[m], 21);
+    mons[m, 1] := sWeek;
+    var dim := DaysInMonth(date);
+    for var d := 1 to 43 do
+    begin
+      var day := (d > offs) and (d <= offs + dim);
+      var str := '   ';
+      if day then
+        str := format(' %2d', [d - offs]);
+      mons[m, 2 + (d - 1) div 7] := mons[m, 2 + (d - 1) div 7] + str;
+    end;
+    offs := (offs + dim) mod 7;
+    date := IncMonth(date, 1);
+  end;
+  writeln(Center('[Snoopy Picture]', nCols * 24 + 4));
+  Writeln(Center(year.ToString, nCols * 24 + 4));
+  writeln;
+
+  for var r := 0 to rows - 1 do
+  begin
+    var s: TArray<string>;
+    SetLength(s, 8);
+    for var c := 0 to nCols - 1 do
+    begin
+      if r * nCols + c > 11 then
+        Break;
+      for var i := 0 to High(mons[r * nCols + c]) do
+      begin
+        var line := mons[r * nCols + c, i];
+        s[i] := s[i] + '   ' + line;
+      end;
+    end;
+
+    for var ss in s do
+    begin
+      writeln(ss, ' ');
+    end;
+    writeln;
+  end;
+
+end;
+
+begin
+  printCalendar(1969, 4);
+  readln;
+end.

Task/Calendar/F-Sharp/calendar.fs

@@ -0,0 +1,71 @@
+let getCalendar year =
+    let day_of_week month year =
+        let t =  [|0; 3; 2; 5; 0; 3; 5; 1; 4; 6; 2; 4|]
+        let y = if month < 3 then year - 1 else year
+        let m = month
+        let d = 1
+        (y + y / 4 - y / 100 + y / 400 + t.[m - 1] + d) % 7
+        //0 = Sunday, 1 = Monday, ...
+
+    let last_day_of_month month year =
+        match month with
+        | 2 -> if (0 = year % 4 && (0 = year % 400 || 0 <> year % 100)) then 29 else 28
+        | 4 | 6 | 9 | 11 -> 30
+        | _ -> 31
+
+    let get_month_calendar year month =
+        let min (x: int, y: int) = if x < y then x else y
+        let ld = last_day_of_month month year
+        let dw = 7 - (day_of_week month year)
+        [|[|1..dw|];
+          [|dw + 1..dw + 7|];
+          [|dw + 8..dw + 14|];
+          [|dw + 15..dw + 21|];
+          [|dw + 22..min(ld, dw + 28)|];
+          [|min(ld + 1, dw + 29)..ld|]|]
+
+    let sb_fold (f:System.Text.StringBuilder -> 'a -> System.Text.StringBuilder) (sb:System.Text.StringBuilder) (xs:'a array)  =
+        for x in xs do (f sb  x) |> ignore
+        sb
+
+    let sb_append (text:string) (sb:System.Text.StringBuilder) = sb.Append(text)
+
+    let sb_appendln sb = sb |> sb_append "\n" |> ignore
+
+    let sb_fold_in_range a b f sb = [|a..b|] |> sb_fold f sb |> ignore
+
+    let mask_builder mask = Printf.StringFormat<string -> string>(mask)
+    let center n (s:string) =
+        let l = (n - s.Length) / 2 + s.Length
+        let f n s = sprintf (mask_builder ("%" + (n.ToString()) + "s")) s
+        (f l s) + (f (n - l) "")
+    let left n (s:string)  = sprintf (mask_builder ("%-" + (n.ToString()) + "s")) s
+    let right n (s:string) = sprintf (mask_builder ("%" + (n.ToString()) + "s")) s
+
+    let array2string xs =
+        let ys = xs |> Array.map (fun x -> sprintf "%2d " x)
+        let sb = ys |> sb_fold (fun sb y -> sb.Append(y)) (new System.Text.StringBuilder())
+        sb.ToString()
+
+    let xsss =
+        let m = get_month_calendar year
+        [|1..12|] |> Array.map (fun i -> m i)
+
+    let months = [|"January"; "February"; "March"; "April"; "May"; "June"; "July"; "August"; "September"; "October"; "November"; "December"|]
+
+    let sb = new System.Text.StringBuilder()
+    sb |> sb_append "\n" |> sb_append (center 74 (year.ToString())) |> sb_appendln
+    for i in 0..3..9 do
+      sb |> sb_appendln
+      sb |> sb_fold_in_range i (i + 2) (fun sb i -> sb |> sb_append (center 21 months.[i]) |> sb_append "      ")
+      sb |> sb_appendln
+      sb |> sb_fold_in_range i (i + 2) (fun sb i -> sb |> sb_append "Su Mo Tu We Th Fr Sa " |> sb_append "      ")
+      sb |> sb_appendln
+      sb |> sb_fold_in_range i (i + 2) (fun sb i -> sb |> sb_append (right 21 (array2string (xsss.[i].[0]))) |> sb_append "      ")
+      sb |> sb_appendln
+      for j = 1 to 5 do
+        sb |> sb_fold_in_range i (i + 2) (fun sb i -> sb |> sb_append (left 21 (array2string (xsss.[i].[j]))) |> sb_append "      ")
+        sb |> sb_appendln
+    sb.ToString()
+
+let printCalendar year = getCalendar year

Task/Calendar/Factor/calendar.factor

@@ -0,0 +1,12 @@
+USING: arrays calendar.format grouping io.streams.string kernel
+math.ranges prettyprint sequences sequences.interleaved ;
+IN: rosetta-code.calendar
+
+: calendar ( year -- )
+    12 [1,b] [ 2array [ month. ] with-string-writer ] with map
+    3 <groups> [ "   " <interleaved> ] map 5 " " <repetition>
+    <interleaved> simple-table. ;
+
+: calendar-demo ( -- ) 1969 calendar ;
+
+MAIN: calendar-demo

Task/Calendar/Fortran/calendar.f

@@ -0,0 +1,283 @@
+       MODULE DATEGNASH	!Assorted vexations. Time and calendar games, with local flavourings added.
+
+       TYPE DateBag		!Pack three parts into one.
+        INTEGER DAY,MONTH,YEAR	!The usual suspects.
+       END TYPE DateBag		!Simple enough.
+
+       CHARACTER*9 MONTHNAME(12),DAYNAME(0:6)	!Re-interpretations.
+       PARAMETER (MONTHNAME = (/"January","February","March","April",
+     1  "May","June","July","August","September","October","November",
+     2  "December"/))
+       PARAMETER (DAYNAME = (/"Sunday","Monday","Tuesday","Wednesday",
+     1  "Thursday","Friday","Saturday"/))	!Index this array with DayNum mod 7.
+       CHARACTER*3 MTHNAME(12)		!The standard abbreviations.
+       PARAMETER (MTHNAME = (/"JAN","FEB","MAR","APR","MAY","JUN",
+     1  "JUL","AUG","SEP","OCT","NOV","DEC"/))
+
+       INTEGER*4 JDAYSHIFT		!INTEGER*2 just isn't enough.
+       PARAMETER (JDAYSHIFT = 2415020)	!Thus shall 31/12/1899 give 0, a Sunday, via DAYNUM.
+       CONTAINS
+       INTEGER FUNCTION LSTNB(TEXT)  !Sigh. Last Not Blank.
+Concocted yet again by R.N.McLean (whom God preserve) December MM.
+Code checking reveals that the Compaq compiler generates a copy of the string and then finds the length of that when using the latter-day intrinsic LEN_TRIM. Madness!
+Can't   DO WHILE (L.GT.0 .AND. TEXT(L:L).LE.' ')	!Control chars. regarded as spaces.
+Curse the morons who think it good that the compiler MIGHT evaluate logical expressions fully.
+Crude GO TO rather than a DO-loop, because compilers use a loop counter as well as updating the index variable.
+Comparison runs of GNASH showed a saving of ~3% in its mass-data reading through the avoidance of DO in LSTNB alone.
+Crappy code for character comparison of varying lengths is avoided by using ICHAR which is for single characters only.
+Checking the indexing of CHARACTER variables for bounds evoked astounding stupidities, such as calculating the length of TEXT(L:L) by subtracting L from L!
+Comparison runs of GNASH showed a saving of ~25-30% in its mass data scanning for this, involving all its two-dozen or so single-character comparisons, not just in LSTNB.
+        CHARACTER*(*),INTENT(IN):: TEXT	!The bumf. If there must be copy-in, at least there need not be copy back.
+        INTEGER L		!The length of the bumf.
+         L = LEN(TEXT)		!So, what is it?
+    1    IF (L.LE.0) GO TO 2	!Are we there yet?
+         IF (ICHAR(TEXT(L:L)).GT.ICHAR(" ")) GO TO 2	!Control chars are regarded as spaces also.
+         L = L - 1		!Step back one.
+         GO TO 1		!And try again.
+    2    LSTNB = L		!The last non-blank, possibly zero.
+        RETURN			!Unsafe to use LSTNB as a variable.
+       END FUNCTION LSTNB	!Compilers can bungle it.
+      CHARACTER*2 FUNCTION I2FMT(N)	!These are all the same.
+       INTEGER*4 N			!But, the compiler doesn't offer generalisations.
+        IF (N.LT.0) THEN	!Negative numbers cop a sign.
+          IF (N.LT.-9) THEN	!But there's not much room left.
+            I2FMT = "-!"	!So this means 'overflow'.
+           ELSE			!Otherwise, room for one negative digit.
+            I2FMT = "-"//CHAR(ICHAR("0") - N)	!Thus. Presume adjacent character codes, etc.
+          END IF		!So much for negative numbers.
+        ELSE IF (N.LT.10) THEN	!Single digit positive?
+          I2FMT = " " //CHAR(ICHAR("0") + N)	!Yes. This.
+        ELSE IF (N.LT.100) THEN	!Two digit positive?
+          I2FMT = CHAR(N/10      + ICHAR("0"))	!Yes.
+     1           //CHAR(MOD(N,10) + ICHAR("0")) !These.
+        ELSE			!Otherwise,
+          I2FMT = "+!" 	!Positive overflow.
+        END IF			!So much for that.
+      END FUNCTION I2FMT	!No WRITE and FORMAT unlimbering.
+      CHARACTER*8 FUNCTION I8FMT(N)	!Oh for proper strings.
+       INTEGER*4 N
+       CHARACTER*8 HIC
+        WRITE (HIC,1) N
+    1   FORMAT (I8)
+        I8FMT = HIC
+      END FUNCTION I8FMT
+
+      SUBROUTINE SAY(OUT,TEXT)	!Gutted version that maintains no file logging output, etc.
+       INTEGER OUT
+       CHARACTER*(*) TEXT
+        WRITE (6,1) TEXT(1:LSTNB(TEXT))
+    1   FORMAT (A)
+      END SUBROUTINE SAY
+
+       INTEGER*4 FUNCTION DAYNUM(YY,M,D)	!Computes (JDayN - JDayShift), not JDayN.
+C   Conversion from a Gregorian calendar date to a Julian day number, JDayN.
+C   Valid for any Gregorian calendar date producing a Julian day number
+C greater than zero, though remember that the Gregorian calendar
+C was not used before y1582m10d15 and often, not after that either.
+C thus in England (et al) when Wednesday 2'nd September 1752 (Julian style)
+C was followed by Thursday the 14'th, occasioning the Eleven Day riots
+C because creditors demanded a full month's payment instead of 19/30'ths.
+C   The zero of the Julian day number corresponds to the first of January
+C 4713BC on the *Julian* calendar's naming scheme, as extended backwards
+C with current usage into epochs when it did not exist: the proleptic Julian calendar.
+c This function employs the naming scheme of the *Gregorian* calendar,
+c and if extended backwards into epochs when it did not exist (thus the
+c proleptic Gregorian calendar) it would compute a zero for y-4713m11d24 *if*
+c it is supposed there was a year zero between 1BC and 1AD (as is convenient
+c for modern mathematics and astronomers and their simple calculations), *but*
+c 1BC immediately preceeds 1AD without any year zero in between (and is a leap year)
+c thus the adjustment below so that the date is y-4714m11d24 or 4714BCm11d24,
+c not that this name was in use at the time...
+c   Although the Julian calendar (introduced by himself in what we would call 45BC,
+c which was what the Romans occasionally called 709AUC) was provoked by the
+c "years of confusion" resulting from arbitrary application of the rules
+c for the existing Roman calendar, other confusions remain unresolved,
+c so precise dating remains uncertain despite apparently precise specifications
+c (and much later, Dennis the Short chose wrongly for the birth of Christ)
+c and the Roman practice of inclusive reckoning meant that every four years
+c was interpreted as every third (by our exclusive reckoning) so that the
+c leap years were not as we now interpret them. This was resolved by Augustus
+c but exactly when (and what date name is assigned) and whose writings used
+c which system at the time of writing is a matter of more confusion,
+c and this has continued for centuries.
+C   Accordingly, although an algorithm may give a regular sequence of date names,
+c that does not mean that those date names were used at the time even if the
+c calendar existed then, because the interpretation of the algorithm varied.
+c This in turn means that a date given as being on the Julian calendar
+c prior to about 10AD is not as definite as it may appear and its alignment
+c with the astronomical day number is uncertain even though the calculation
+c is quite definite.
+c
+C   Computationally, year 1 is preceded by year 0, in a smooth progression.
+C But there was never a year zero despite what astronomers like to say,
+C so the formula's year 0 corresponds to 1BC, year -1 to 2BC, and so on back.
+C Thus y-4713 in this counting would be 4714BC on the Gregorian calendar,
+C were it to have existed then which it didn't.
+C   To conform to the civil usage, the incoming YY, presumed a proper BC (negative)
+C and AD (positive) year is converted into the computational counting sequence, Y,
+C and used in the formula. If a YY = 0 is (improperly) offered, it will manifest
+C as 1AD. Thus YY = -4714 will lead to calculations with Y = -4713.
+C Thus, 1BC is a leap year on the proleptic Gregorian calendar.
+C   For their convenience, astronomers decreed that a day starts at noon, so that
+C in Europe, observations through the night all have the same day number.
+C The current Western civil calendar however has the day starting just after midnight
+C and that day's number lasts until the following midnight.
+C
+C   There is no constraint on the values of D, which is just added as it stands.
+C This means that if D = 0, the daynumber will be that of the last day of the
+C previous month. Likewise, M = 0 or M = 13 will wrap around so that Y,M + 1,0
+C will give the last day of month M (whatever its length) as one day before
+C the first day of the next month.
+C
+C   Example: Y = 1970, M = 1, D = 1;  JDAYN = 2440588, a Thursday but MOD(2440588,7) = 3.
+C   and with the adjustment JDAYSHIFT, DAYNUM = 25568; mod 7 = 4 and DAYNAME(4) = "Thursday".
+C   The Julian Day number 2440588.0 is for NOON that Thursday, 2440588.5 is twelve hours later.
+C   And Julian Day number 2440587.625 is for three a.m. Thursday.
+C
+C   DAYNUM and MUNYAD are the infamous routines of H. F. Fliegel and T.C. van Flandern,
+C   presented in Communications of the ACM, Vol. 11, No. 10 (October, 1968).
+Carefully typed in again by R.N.McLean (whom God preserve) December XXMMIIX.
+C   Though I remain puzzled as to why they used I,J,K for Y,M,D,
+C given that the variables were named in the INTEGER statement anyway.
+        INTEGER*4 JDAYN		!Without rebasing, this won't fit in INTEGER*2.
+        INTEGER YY,Y,M,MM,D	!NB! Full year number, so 1970, not 70.
+Caution: integer division in Fortran does not produce fractional results.
+C The fractional part is discarded so that 4/3 gives 1 and -4/3 gives -1.
+C Thus 4/3 might be Trunc(4/3) or 4 div 3 in other languages. Beware of negative numbers!
+         Y = YY		!I can fiddle this copy without damaging the original's value.
+         IF (Y.LT.1) Y = Y + 1	!Thus YY = -2=2BC, -1=1BC, +1=1AD, ... becomes Y = -1, 0, 1, ...
+         MM = (M - 14)/12	!Calculate once. Note that this is integer division, truncating.
+         JDAYN = D - 32075	!This is the proper astronomer's Julian Day Number.
+     a    + 1461*(Y + 4800  + MM)/4
+     b    +  367*(M - 2     - MM*12)/12
+     c    -    3*((Y + 4900 + MM)/100)/4
+         DAYNUM = JDAYN - JDAYSHIFT	!Thus, *NOT* the actual *Julian* Day Number.
+       END FUNCTION DAYNUM		!But one such that Mod(n,7) gives day names.
+
+Could compute the day of the year somewhat as follows...
+c  DN:=D + (61*Month + (Month div 8)) div 2 - 30
+c        + if Month > 2 then FebLength - 30 else 0;
+
+       TYPE(DATEBAG) FUNCTION MUNYAD(DAYNUM)	!Oh for palindromic programming!
+Conversion from a Julian day number to a Gregorian calendar date. See JDAYN/DAYNUM.
+        INTEGER*4 DAYNUM,JDAYN	!Without rebasing, this won't fit in INTEGER*2.
+        INTEGER Y,M,D,L,N		!Y will be a full year number: 1950 not 50.
+         JDAYN = DAYNUM + JDAYSHIFT	!Revert to a proper Julian day number.
+         L = JDAYN + 68569	!Further machinations of H. F. Fliegel and T.C. van Flandern.
+         N = 4*L/146097
+         L = L - (146097*N + 3)/4
+         Y = 4000*(L + 1)/1461001
+         L = L - 1461*Y/4 + 31
+         M = 80*L/2447
+         D = L - 2447*M/80
+         L = M/11
+         M = M + 2 - 12*L
+         Y = 100*(N - 49) + Y + L
+         IF (Y.LT.1) Y = Y - 1	!The other side of conformity to BC/AD, as in DAYNUM.
+         MUNYAD%YEAR  = Y	!Now place for the world to see.
+         MUNYAD%MONTH = M
+         MUNYAD%DAY   = D
+       END FUNCTION MUNYAD	!A year has 365.2421988 days...
+
+       INTEGER FUNCTION PMOD(N,M)	!Remainder, mod M; always positive even if N is negative.
+c   For date calculations, the MOD function is expected to yield positive remainders,
+c in line with the idea that MOD(a,b) = MOD(a ± b,b) as is involved in shifting the zero
+c of the daynumber count by a multiple of seven when considering the day of the week.
+c For this reason, the zero day was chosen to be 31/12/1899, a Sunday, so that all
+c day numbers would be positive. But, there was generation at Reefton in 1886.
+c   For some computers, the positive interpretation is implemented, for others, not.
+c In the case MOD(N,M) = N - Truncate(N/M)*M, MOD(-6,7) = -6 even though MOD(1,7) = 1.
+        INTEGER N,M			!The numbers. M presumed positive.
+         PMOD = MOD(MOD(N,M) + M,M)	!Double do does de deed.
+       END FUNCTION PMOD		!Simple enough.
+
+      SUBROUTINE CALENDAR(Y1,Y2,COLUMNS)	!Print a calendar, with holiday annotations.
+Careful with the MOD function. MOD(-6,7) may be negative on some systems, positive on others. Thus, PMOD.
+       INTEGER Y1,Y2,YEAR		!Ah yes. Year stuff.
+       INTEGER M,M1,M2,MONTH		!And within each year are the months.
+       INTEGER*4 DN1,DN2,DN,D		!But days are handled via day numbers.
+       INTEGER W,G			!Layout: width and gap.
+       INTEGER L,LINE			!Vertical layout.
+       INTEGER COL,COLUMNS,COLWIDTH	!Horizontal layout.
+       INTEGER CODE			!Days are not all alike.
+       CHARACTER*200 STRIPE(6),SPECIAL(6),MLINE,DLINE	!Scratchpads.
+        IF (Y1.LE.0) CALL SAY(MSG,"Despite the insinuations of "
+     1   //"astronomers seduced by the ease of their arithmetic, "
+     2   //"there is no year zero. 1AD is preceded by 1BC, "
+     3   //"corresponding to year -1, 2BC to year -2, etc.")
+        IF (Y1.LT.1582) CALL SAY(MSG,"This Gregorian calendar"
+     1   //" scheme did not exist prior to 1582.")
+c        COLUMNS = 4	!Number of months across the page.
+c        W = 4		!Width of a day's field.
+c        G = 3		!Added gap between month columns.
+        W = 3		!Abandon the annotation of the day's class, so just a space and two digits.
+        G = 1		!Set the gap to one.
+        COLWIDTH = 7*W + G	!Seven days to a week, plus a gap.
+      Y:DO YEAR = Y1,Y2		!Step through the years.
+          CALL SAY(MSG,"")	!Space out between each year's schedule.
+          IF (YEAR.EQ.0) THEN	!This year number is improper.
+            CALL SAY(MSG,"There is no year zero.")	!Declare correctness.
+            CYCLE Y		!Skip this year.
+          END IF		!Otherwise, no evasions.
+          MLINE = ""		!Prepare a field..
+          L = (COLUMNS*COLWIDTH - G - 8)/2	!Find the centre.
+          IF (YEAR.GT.0) THEN	!Ordinary Anno Domine years?
+            MLINE(L:) = I8FMT(YEAR)	!Yes. Place the year number.
+           ELSE			!Otherwise, we're in BC.
+            MLINE(L - 1:) = I8FMT(-YEAR)//"BC"	!There is no year zero.
+          END IF		!So much for year games.
+          CALL SAY(MSG,MLINE)		!Splot the year.
+          DO MONTH = 1,12,COLUMNS	!Step through the months of this YEAR.
+            M1 = MONTH			!The first of this lot.
+            M2 = MIN(12,M1 + COLUMNS - 1)	!The last.
+            MLINE = ""			!Scrub the month names.
+            DLINE = ""			!Wipe the day names in case COLUMNS does not divide 12.
+            STRIPE = ""			!Scrub the day table.
+            SPECIAL = ""		!And the associated special day remarks.
+c            L0 = W - 1			!Locate the first day number's first column.
+            L0 = 1			!Cram: no space in front of the Sunday day-of-the-month.
+            DO M = M1,M2		!Work through the months.
+              L = (COLWIDTH - G - LSTNB(MONTHNAME(M)))/2 - 1	!Centre the month name.
+              MLINE(L0 + L:) = MONTHNAME(M)	!Splot.
+              DO D = 0,6		!Prepare this month's day name heading.
+                L = L0 + (3 - W) + D*W	!Locate its first column.
+                DLINE(L:L + 2) = DAYNAME(D)(1:W - 1)	!Squish.
+              END DO		!On to the next day.
+              DN1 = DAYNUM(YEAR,M,1)	!Day number of the first day of the month.
+              DN2 = DAYNUM(YEAR,M + 1,0)!Thus the last, without annoyance.
+              COL = MOD(PMOD(DN1,7) + 7,7)	!What day of the week is the first day?
+              LINE = 1			!Whichever it is, it is on the first line.
+              D = 1			!Day of the month, not number of the day.
+              DO DN = DN1,DN2		!Step through the day numbers of this month.
+                L = L0 + COL*W		!Finger the starting column.
+                STRIPE(LINE)(L:L + 1) = I2FMT(D)	!Place the two-digit day number.
+                D = D + 1		!Advance to the next day of the current month
+                COL = COL + 1		!So, one more day along in the week.
+                IF (COL.GT.6) THEN	!A fresh week is needed?
+                  LINE = LINE + 1	!Yes.
+                  COL = 0		!Start the new week.
+                END IF		!So much for the end of a week.
+              END DO		!On to the next day of this month.
+              L0 = L0 + 7*W + G	!Locate the start column of the next month's column.
+            END DO	!On to the next month in this layer.
+            CALL SAY(MSG,MLINE)	!Name the months.
+C            CALL SAY(MSG,"")	!Set off.
+            CALL SAY(MSG,DLINE)	!Give the day name headings.
+            DO LINE = 1,6	!Now roll the day number table.
+              IF (STRIPE(LINE).NE."") THEN	!Perhaps there was no use of the sixth line.
+                CALL SAY(MSG,STRIPE(LINE))	!Ah well. Show the day numbers.
+              END IF				!So much for that week line.
+            END DO			!On to the next week line.
+          END DO		!On to the next batch of months of the YEAR.
+        END DO Y		!On to the next YEAR.
+        CALL SAY(MSG,"")	!Take a breath.
+      END SUBROUTINE CALENDAR	!Enough of this.
+      END MODULE DATEGNASH	!An ad-hoc assemblage.
+
+      PROGRAM SHOW1968		!Put it to the test.
+       USE DATEGNASH
+       INTEGER NCOL
+        DO NCOL = 1,6
+          CALL CALENDAR(1969,1969,NCOL)
+        END DO
+      END

Task/Calendar/FreeBASIC/calendar.basic

@@ -0,0 +1,125 @@
+' version 17-02-2016
+' compile with: fbc -s console
+
+' TRUE/FALSE are built-in constants since FreeBASIC 1.04
+' For older versions they have to be defined.
+#Ifndef TRUE
+    #Define FALSE 0
+    #Define TRUE Not FALSE
+#EndIf
+
+Function WD(m As Integer, d As Integer, y As Integer) As Integer
+    ' Zellerish
+    ' 0 = Sunday, 1 = Monday, 2 = Tuesday, 3 = Wednesday
+    ' 4 = Thursday, 5 = Friday, 6 = Saturday
+
+    If m < 3 Then        ' if m = 1 or m = 2 then
+        m += 12
+        y -= 1
+    End If
+    Return (y + (y \ 4) - (y \ 100) + (y \ 400) + d + ((153 * m + 8) \ 5)) Mod 7
+End Function
+
+Function LEAPYEAR(y As Integer) As Integer
+    If (y Mod 4) <> 0 Then Return FALSE
+    If (y Mod 100) = 0 AndAlso (y Mod 400) <> 0 Then Return FALSE
+    Return TRUE
+End Function
+
+' ------=< main >=------
+
+Dim As String wdn = "Mo Tu We Th Fr Sa Su"  ' weekday names
+Dim As String mo(1 To 12) => {"January", "February", "March", "April", _
+                         "May", "June", "July", "August", "September", _
+                                    "October", "November", "December"}
+Dim As String tmp1, tmp2, d(1 To 12)
+
+Dim As UInteger ml(1 To 12) => {31,28,31,30,31,30,31,31,30,31,30,31}
+Dim As UInteger i, i1, j, k, y = 1969
+Dim As UInteger m_row = 6
+
+Do
+    While InKey <> "" : Wend  ' clear keyboard buffer
+    Print : Print " For wich year do want a calendar"
+    Print " Year must be greater then 1752"
+    Input " Input year (enter = 1969)";tmp1
+    If tmp1 = "" Then Exit Do
+    i = Val(tmp1)
+    If i < 1752 Then
+        Print
+        Print " Can only make a calendar for a year after 1752"
+        Beep : Sleep 5000, 1 : Print
+    Else
+        y = i : Exit Do
+    End If
+Loop
+
+Cls
+Do
+    While InKey <> "" : Wend  ' clear keyboard buffer
+    Print : Print " Make device choice"
+    Print " 132 characters Line printer, 6x2 months (Enter or 1)"
+    Print " 80x43 display,               3x4 months          (2)"
+    Do
+        tmp1 = InKey
+        If tmp1 = Chr(13) Or tmp1 = "1" Then Exit Do, Do
+        If tmp1 = "2" Then
+            m_row = 3
+            Exit Do, Do
+        End If
+    Loop Until tmp1 <> ""
+    Print : Print " Enter, 1 or 2 only"
+    Beep : Sleep 5000, 1 : Print
+Loop
+Cls
+
+Dim As UInteger char_line = m_row * 22 - 1
+If LEAPYEAR(y) = TRUE Then ml(2) = 29
+
+tmp1 = ""
+For i = 1 To 31
+    tmp1 = tmp1 + Right(("  " + Str(i)), 3)
+Next
+
+For i = 1 To 12
+    tmp2 = ""
+    j = WD(i,1, y)
+    If j = 0 Then j = 7
+    j = j - 1
+    tmp2 = Space(j * 3) + Left(tmp1, ml(i) * 3) + Space(21)
+    d(i) = tmp2
+Next
+
+Print
+tmp1 = Str(y)
+Print Space((char_line + (char_line And 1) - Len(tmp1)) \ 2); tmp1
+Print
+
+tmp2 = " "    ' make the weekday names line
+For i = 1 To m_row
+    tmp2 = tmp2 + wdn
+    If i < m_row Then tmp2 = tmp2 + "  "
+Next
+
+For i = 1 To 12 Step m_row
+    tmp1 = ""
+    For j = i To i + m_row -2 ' make the month names line
+        tmp1 = tmp1 + Left(Space((22 - Len(mo(j))) \ 2) + mo(j) + Space(21), 22)
+    Next
+    tmp1 = tmp1 + Space((22 - Len(mo(i + m_row -1))) \ 2) + mo(i + m_row -1)
+    Print tmp1
+    Print tmp2
+    For j = 1 To 85 Step 21
+        For k = i To i + m_row -2
+            Print Mid(d(k), j ,21); " ";
+        Next
+        Print Mid(d(i + m_row -1), j ,21)
+    Next
+    Print
+Next
+
+' empty keyboard buffer
+While InKey <> "" : Wend
+'Print : Print "hit any key to end program
+Sleep
+End

Task/Calendar/FutureBasic/calendar-1.basic

@@ -0,0 +1,12 @@
+window 1, @"Calendar", (0, 0, 520, 520 )
+
+Str255 a
+
+open "UNIX", 1,"cal 1969"
+do
+  line input #1, a
+  print a
+until eof(1)
+close 1
+
+HandleEvents

Task/Calendar/FutureBasic/calendar-2.basic

@@ -0,0 +1,17 @@
+include "NSLog.incl"
+
+local fn RunCommand( command as CFStringRef ) as CFStringRef
+  TaskRef tsk = fn TaskInit
+  TaskSetExecutableURL( tsk, fn URLFileURLWithPath( @"/bin/sh" ) )
+  TaskSetArguments( tsk, @[@"-c",command] )
+  PipeRef pip = fn PipeInit
+  TaskSetStandardOutput( tsk, pip )
+  FileHandleRef fh = fn PipeFileHandleForReading( pip )
+  fn TaskLaunch( tsk, NULL )
+  CFDataRef dta = fn FileHandleReadDataToEndOfFile( fh, NULL )
+  CFStringRef outputStr = fn StringWithData( dta, NSUTF8StringEncoding )
+end fn = outputStr
+
+NSLog( @"%@", fn RunCommand( @"cal 1969" ) )
+
+HandleEvents

Task/Calendar/Gambas/calendar.gambas

@@ -0,0 +1,5 @@
+Public Sub Main()
+
+Shell "cal 1969"
+
+End

Task/Calendar/Go/calendar.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+const pageWidth = 80
+
+func main() {
+	printCal(1969)
+}
+
+func printCal(year int) {
+	thisDate := time.Date(year, 1, 1, 1, 1, 1, 1, time.UTC)
+	var (
+		dayArr                  [12][7][6]int // month, weekday, week
+		month, lastMonth        time.Month
+		weekInMonth, dayInMonth int
+	)
+	for thisDate.Year() == year {
+		if month = thisDate.Month(); month != lastMonth {
+			weekInMonth = 0
+			dayInMonth = 1
+		}
+		weekday := thisDate.Weekday()
+		if weekday == 0 && dayInMonth > 1 {
+			weekInMonth++
+		}
+		dayArr[int(month)-1][weekday][weekInMonth] = thisDate.Day()
+		lastMonth = month
+		dayInMonth++
+		thisDate = thisDate.Add(time.Hour * 24)
+	}
+	centre := fmt.Sprintf("%d", pageWidth/2)
+	fmt.Printf("%"+centre+"s\n\n", "[SNOOPY]")
+	centre = fmt.Sprintf("%d", pageWidth/2-2)
+	fmt.Printf("%"+centre+"d\n\n", year)
+	months := [12]string{
+		" January ", " February", "  March  ", "  April  ",
+		"   May   ", "   June  ", "   July  ", "  August ",
+		"September", " October ", " November", " December"}
+	days := [7]string{"Su", "Mo", "Tu", "We", "Th", "Fr", "Sa"}
+	for qtr := 0; qtr < 4; qtr++ {
+		for monthInQtr := 0; monthInQtr < 3; monthInQtr++ { // Month names
+			fmt.Printf("      %s           ", months[qtr*3+monthInQtr])
+		}
+		fmt.Println()
+		for monthInQtr := 0; monthInQtr < 3; monthInQtr++ { // Day names
+			for day := 0; day < 7; day++ {
+				fmt.Printf(" %s", days[day])
+			}
+			fmt.Printf("     ")
+		}
+		fmt.Println()
+		for weekInMonth = 0; weekInMonth < 6; weekInMonth++ {
+			for monthInQtr := 0; monthInQtr < 3; monthInQtr++ {
+				for day := 0; day < 7; day++ {
+					if dayArr[qtr*3+monthInQtr][day][weekInMonth] == 0 {
+						fmt.Printf("   ")
+					} else {
+						fmt.Printf("%3d", dayArr[qtr*3+monthInQtr][day][weekInMonth])
+					}
+				}
+				fmt.Printf("     ")
+			}
+			fmt.Println()
+		}
+		fmt.Println()
+	}
+}

Task/Calendar/Haskell/calendar.hs

@@ -0,0 +1,90 @@
+import qualified Data.Text as T
+import Data.Time
+import Data.Time.Calendar
+import Data.Time.Calendar.WeekDate
+import Data.List.Split (chunksOf)
+import Data.List
+
+data Day = Su | Mo | Tu | We | Th | Fr | Sa
+           deriving (Show, Eq, Ord, Enum)
+
+data Month = January | February | March
+           | April   | May      | June
+           | July    | August   | September
+           | October | November | December
+             deriving (Show, Eq, Ord, Enum)
+
+monthToInt :: Month -> Int
+monthToInt = (+ 1) . fromEnum
+
+dayFromDate :: Integer -> Month -> Int -> Int
+dayFromDate year month day = day' `mod` 7
+    where (_, _, day') = toWeekDate $ fromGregorian year (monthToInt month) day
+
+nSpaces :: Int -> T.Text
+nSpaces n = T.replicate n (T.pack " ")
+
+space :: T.Text
+space = nSpaces 1
+
+calMarginWidth = 3
+
+calMargin :: T.Text
+calMargin = nSpaces calMarginWidth
+
+calWidth = 20
+
+listMonth :: Integer -> Month -> [T.Text]
+listMonth year month = [monthHeader, weekHeader] ++ weeks'
+    where
+      monthHeader = (T.center calWidth ' ') . T.pack $ show month
+
+      weekHeader = (T.intercalate space) $ map (T.pack . show) [(Su)..]
+
+      monthLength = toInteger $
+                    gregorianMonthLength year $
+                    monthToInt month
+
+      firstDay = dayFromDate year month 1
+
+      days = replicate firstDay (nSpaces 2) ++
+             map ((T.justifyRight 2 ' ') . T.pack . show) [1..monthLength]
+
+      weeks = map (T.justifyLeft calWidth ' ') $
+              map (T.intercalate space) $
+              chunksOf 7 days
+
+      weeks' = weeks ++ replicate (6 - length weeks) (nSpaces calWidth)
+
+listCalendar :: Integer -> Int -> [[[T.Text]]]
+listCalendar year calColumns = (chunksOf calColumns) . (map (listMonth year)) $
+                               enumFrom January
+
+calColFromCol :: Int -> Int
+calColFromCol columns = c + if r >= calWidth then 1 else 0
+    where (c, r) = columns `divMod` (calWidth + calMarginWidth)
+
+colFromCalCol :: Int -> Int
+colFromCalCol calCol = calCol * calWidth + ((calCol - 1) * calMarginWidth)
+
+center :: Int -> String -> String
+center i a = T.unpack . (T.center i ' ') $ T.pack a
+
+printCal :: [[[T.Text]]] -> IO ()
+printCal = mapM_ f where
+  f c = mapM_ (putStrLn . T.unpack) rows
+    where rows = map (T.intercalate calMargin) $ transpose c
+
+printCalendar :: Integer -> Int -> IO ()
+printCalendar year columns =
+    if columns < 20
+    then putStrLn $ "Cannot print less than 20 columns"
+    else do
+      putStrLn $ center columns' "[Maybe Snoopy]"
+      putStrLn $ center columns' $ show year
+      putStrLn ""
+      printCal $ listCalendar year calcol'
+    where
+      calcol' = calColFromCol columns
+
+      columns' = colFromCalCol calcol'

Task/Calendar/Huginn/calendar.huginn

@@ -0,0 +1,61 @@
+import DateTime as dt;
+import Algorithms as algo;
+import Text as text;
+
+class Calendar {
+  _monthNames_ = none;
+  _dayNames_ = none;
+  constructor() {
+    t = dt.now();
+    _monthNames_ = algo.materialize( algo.map( algo.range( 1, 13 ), @[t]( m ) { dt.format( "%B", t.set_date( 1, m, 1 ) ); } ), tuple );
+    _dayNames_ = algo.materialize( algo.map( algo.range( 1, 8 ), @[t]( d ) { dt.format( "%a", t.set_date( 1, 1, d ) )[:2]; } ), tuple );
+  }
+  print_year( year_, cols_ ) {
+    t = dt.now();
+    print( "{:^66d}\n".format( year_ ) );
+    for ( rm : algo.range( 12 / cols_ ) ) {
+      m = rm * cols_;
+      print( text.repeat( "{:^22s}", cols_ ).format( _monthNames_[m:m + cols_]... ) + "\n" );
+      day = [];
+      daysInMonth = [];
+      for ( mc : algo.range( cols_ ) ) {
+        print( " {} {} {} {} {} {} {} ".format( _dayNames_... ) );
+        t.set_date( year_, m + mc + 1, 1 );
+        day.push( - t.get_day_of_week() + 1 );
+        daysInMonth.push( t.get_days_in_month() );
+      }
+      print( "\n" );
+      haveDay = true;
+      while ( haveDay ) {
+        haveDay = false;
+        for ( mc : algo.range( cols_ ) ) {
+          for ( d : algo.range( 7 ) ) {
+            if ( ( day[mc] > 0 ) && ( day[mc] <= daysInMonth[mc] ) ) {
+              print( " {:2d}".format( day[mc] ) );
+              haveDay = true;
+            } else {
+              print( "   " );
+            }
+            day[mc] += 1;
+          }
+          print( " " );
+        }
+        print( "\n" );
+      }
+    }
+  }
+}
+
+main( argv_ ) {
+  cal = Calendar();
+  cols = size( argv_ ) > 2 ? integer( argv_[2] ) : 3;
+  if ( 12 % cols != 0 ) {
+    cols = 3;
+  }
+  cal.print_year(
+    size( argv_ ) > 1
+      ? integer( argv_[1] )
+      : dt.now().get_year(),
+    cols
+  );
+}

Task/Calendar/Icon/calendar.icon

@@ -0,0 +1,45 @@
+procedure main(A)
+   printCalendar(\A[1]|1969)	
+end
+
+procedure printCalendar(year)          #: Print a 3 column x 80 char calendar
+   cols := 3                                        # fixed width
+   mons := []                                       # table of months
+   "January February March April May June " ||
+   "July August September October November December " ?
+          while put(mons, tab(find(" "))) do move(1)
+
+   write(center("[Snoopy Picture]",cols * 24 + 4))  # mandatory ..
+   write(center(year,cols * 24 + 4), "\n")          # ... headers
+
+   M := list(cols)                                  # coexpr container
+   every  mon := 0 to 9 by cols do {                # go through months by cols
+      writes("    ")
+      every i := 1 to cols do {
+         writes(center(mons[mon+i],24))             # header months
+         M[i] := create CalendarFormatWeek(year,mon + i)  # formatting coexpr
+         }
+      write()
+      every 1 to 7 do {                             # 1 to max rows
+         every c := 1 to cols do {                  # for each column
+            writes("    ")
+            every 1 to 7 do writes(right(@M[c],3))  # each row day element
+            }
+         write()
+         }
+      }
+   return
+end
+
+link datetime
+
+procedure CalendarFormatWeek(year,m)                #: Format Week for Calendar
+   static D
+   initial D := [31,28,31,30,31,30,31,31,30,31,30,31]
+
+   every suspend "Su"|"Mo"|"Tu"|"We"|"Th"|"Fr"|"Sa"          # header
+   every 1 to (d := (julian(m,1,year)+1)%7) do suspend ""    # lead day alignment
+   every suspend 1 to D[m] do d +:= 1                        # days
+   if m = 2 & IsLeapYear(year) then suspend (d +:= 1, 29)    # LY adjustment
+   every d to (6*7) do suspend ""                            # trailer alignment
+end

Task/Calendar/J/calendar-1.j

@@ -0,0 +1,5 @@
+require 'dates format'               NB. J6.x
+require 'dates general/misc/format'  NB. J7.x
+calBody=: (1 1 }. _1 _1 }. ":)@(-@(<.@%&22)@[ ]\ calendar@])
+calTitle=: (<: - 22&|)@[ center '[Insert Snoopy here]' , '' ,:~ ":@]
+formatCalendar=: calTitle , calBody

Task/Calendar/J/calendar-2.j

@@ -0,0 +1,39 @@
+   80 formatCalendar 1969
+                      [Insert Snoopy here]
+                              1969
+
+         Jan         │         Feb         │         Mar
+ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa
+           1  2  3  4│                    1│                    1
+  5  6  7  8  9 10 11│  2  3  4  5  6  7  8│  2  3  4  5  6  7  8
+ 12 13 14 15 16 17 18│  9 10 11 12 13 14 15│  9 10 11 12 13 14 15
+ 19 20 21 22 23 24 25│ 16 17 18 19 20 21 22│ 16 17 18 19 20 21 22
+ 26 27 28 29 30 31   │ 23 24 25 26 27 28   │ 23 24 25 26 27 28 29
+                     │                     │ 30 31
+─────────────────────┼─────────────────────┼─────────────────────
+         Apr         │         May         │         Jun
+ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa
+        1  2  3  4  5│              1  2  3│  1  2  3  4  5  6  7
+  6  7  8  9 10 11 12│  4  5  6  7  8  9 10│  8  9 10 11 12 13 14
+ 13 14 15 16 17 18 19│ 11 12 13 14 15 16 17│ 15 16 17 18 19 20 21
+ 20 21 22 23 24 25 26│ 18 19 20 21 22 23 24│ 22 23 24 25 26 27 28
+ 27 28 29 30         │ 25 26 27 28 29 30 31│ 29 30
+                     │                     │
+─────────────────────┼─────────────────────┼─────────────────────
+         Jul         │         Aug         │         Sep
+ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa
+        1  2  3  4  5│                 1  2│     1  2  3  4  5  6
+  6  7  8  9 10 11 12│  3  4  5  6  7  8  9│  7  8  9 10 11 12 13
+ 13 14 15 16 17 18 19│ 10 11 12 13 14 15 16│ 14 15 16 17 18 19 20
+ 20 21 22 23 24 25 26│ 17 18 19 20 21 22 23│ 21 22 23 24 25 26 27
+ 27 28 29 30 31      │ 24 25 26 27 28 29 30│ 28 29 30
+                     │ 31                  │
+─────────────────────┼─────────────────────┼─────────────────────
+         Oct         │         Nov         │         Dec
+ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa│ Su Mo Tu We Th Fr Sa
+           1  2  3  4│                    1│     1  2  3  4  5  6
+  5  6  7  8  9 10 11│  2  3  4  5  6  7  8│  7  8  9 10 11 12 13
+ 12 13 14 15 16 17 18│  9 10 11 12 13 14 15│ 14 15 16 17 18 19 20
+ 19 20 21 22 23 24 25│ 16 17 18 19 20 21 22│ 21 22 23 24 25 26 27
+ 26 27 28 29 30 31   │ 23 24 25 26 27 28 29│ 28 29 30 31
+                     │ 30                  │

Task/Calendar/Java/calendar.java

@@ -0,0 +1,57 @@
+import java.text.*;
+import java.util.*;
+
+public class CalendarTask {
+
+    public static void main(String[] args) {
+        printCalendar(1969, 3);
+    }
+
+    static void printCalendar(int year, int nCols) {
+        if (nCols < 1 || nCols > 12)
+            throw new IllegalArgumentException("Illegal column width.");
+
+        Calendar date = new GregorianCalendar(year, 0, 1);
+
+        int nRows = (int) Math.ceil(12.0 / nCols);
+        int offs = date.get(Calendar.DAY_OF_WEEK) - 1;
+        int w = nCols * 24;
+
+        String[] monthNames = new DateFormatSymbols(Locale.US).getMonths();
+
+        String[][] mons = new String[12][8];
+        for (int m = 0; m < 12; m++) {
+
+            String name = monthNames[m];
+            int len = 11 + name.length() / 2;
+            String format = MessageFormat.format("%{0}s%{1}s", len, 21 - len);
+
+            mons[m][0] = String.format(format, name, "");
+            mons[m][1] = " Su Mo Tu We Th Fr Sa";
+            int dim = date.getActualMaximum(Calendar.DAY_OF_MONTH);
+
+            for (int d = 1; d < 43; d++) {
+                boolean isDay = d > offs && d <= offs + dim;
+                String entry = isDay ? String.format(" %2s", d - offs) : "   ";
+                if (d % 7 == 1)
+                    mons[m][2 + (d - 1) / 7] = entry;
+                else
+                    mons[m][2 + (d - 1) / 7] += entry;
+            }
+            offs = (offs + dim) % 7;
+            date.add(Calendar.MONTH, 1);
+        }
+
+        System.out.printf("%" + (w / 2 + 10) + "s%n", "[Snoopy Picture]");
+        System.out.printf("%" + (w / 2 + 4) + "s%n%n", year);
+
+        for (int r = 0; r < nRows; r++) {
+            for (int i = 0; i < 8; i++) {
+                for (int c = r * nCols; c < (r + 1) * nCols && c < 12; c++)
+                    System.out.printf("   %s", mons[c][i]);
+                System.out.println();
+            }
+            System.out.println();
+        }
+    }
+}

Task/Calendar/JavaScript/calendar.js

@@ -0,0 +1,121 @@
+/**
+ * Given a width, return a function that takes a string, and
+ * pads it at both ends to the given width
+ * @param {number} width
+ * @returns {function(string): string}
+ */
+const printCenter = width =>
+    s => s.padStart(width / 2 + s.length / 2, ' ').padEnd(width);
+
+/**
+ * Given an locale string and options, return a function that takes a date
+ * object, and retrurns the date formatted to the locale and options.
+ * @param {string} locale
+ * @param {DateTimeFormatOptions} options
+ * @returns {function(Date): string}
+ */
+const localeName = (locale, options) => {
+  const formatter = new Intl.DateTimeFormat(locale, options);
+  return date => formatter.format(date);
+};
+
+/**
+ * Increment the date by number.
+ * @param {Date} date
+ * @param {number} inc
+ * @returns {Date}
+ */
+const addDay = (date, inc = 1) => {
+  const res = new Date(date.valueOf());
+  res.setDate(date.getDate() + inc);
+  return res;
+}
+
+/**
+ * Given a date, build a string of the week, and return it along with
+ * the mutated date object.
+ * @param {Date} date
+ * @returns {[boolean, Date, string]}
+ */
+const makeWeek = date => {
+  const month = date.getMonth();
+  let [wdi, md, m] = [date.getUTCDay(), date.getDate(), date.getMonth()];
+  const line = Array(7).fill('  ').map((e, i) => {
+    if (i === wdi && m === month) {
+      const result = (md + '').padStart(2, ' ');
+      date = addDay(date);
+      [wdi, md, m] = [date.getUTCDay(), date.getDate(), date.getMonth()];
+      return result;
+    } else {
+      return e;
+    }
+  }).join(' ');
+  return [month !== m, date, line];
+}
+
+/**
+ * Print a nicely formatted calender for the given year in the given locale.
+ * @param {number} year The required year of the calender
+ * @param {string} locale The locale string. Defaults to US English.
+ * @param {number} cols The number of columns for the months. Defaults to 3.
+ * @param {number} coll_space The space between the columns. Defaults to 5.
+ */
+const cal = (year, locale = 'en-US', cols = 3, coll_space = 5) => {
+  const MONTH_LINES = 9;  // Number of lines that make up a month.
+  const MONTH_COL_WIDTH = 20;  // Character width of a month
+  const COL_SPACE = ' '.padStart(coll_space);
+  const FULL_WIDTH = MONTH_COL_WIDTH * cols + coll_space * (cols - 1);
+
+  const collArr = Array(cols).fill('');
+  const monthName = localeName(locale, {month: 'long'});
+  const weekDayShort = localeName(locale, {weekday: 'short'});
+  const monthCenter = printCenter(MONTH_COL_WIDTH);
+  const pageCenter = printCenter(FULL_WIDTH);
+
+  // Get the weekday in the given locale.
+  const sun = new Date(Date.UTC(2017, 0, 1)); // A sunday
+  const weekdays = Array(7).fill('').map((e, i) =>
+      weekDayShort(addDay(sun, i)).padStart(2, ' ').substring(0, 2)).join(' ');
+
+  // The start date.
+  let date = new Date(Date.UTC(year, 0, 1, 0, 0, 0));
+  let nextMonth = true;
+  let line = '';
+  const fullYear = date.getUTCFullYear();
+
+  // The array into which each of the lines are populated.
+  const accumulate = [];
+
+  // Populate the month table heading and columns.
+  const preAmble = date => {
+    accumulate.push(monthCenter(' '))
+    accumulate.push(monthCenter(monthName(date)));
+    accumulate.push(weekdays);
+  };
+
+  // Accumulate the week lines for the year.
+  while (date.getUTCFullYear() === fullYear) {
+    if (nextMonth) {
+      if (accumulate.length % MONTH_LINES !== 0) {
+        accumulate.push(monthCenter(' '))
+      }
+      preAmble(date);
+    }
+    [nextMonth, date, line] = makeWeek(date);
+    accumulate.push(line);
+  }
+
+  // Print the calendar.
+  console.log(pageCenter(String.fromCodePoint(0x1F436)));
+  console.log(pageCenter(`--- ${fullYear} ---`));
+  accumulate.reduce((p, e, i) => {
+    if (!p.includes(i)) {
+      const indexes = collArr.map((e, ci) => i + ci * MONTH_LINES);
+      console.log(indexes.map(e => accumulate[e]).join(COL_SPACE));
+      p.push(...indexes);
+    }
+    return p;
+  }, []);
+};
+
+cal(1969, 'en-US', 3);

Task/Calendar/Jq/calendar-1.jq

@@ -0,0 +1,11 @@
+def nwise($n):
+  def n: if length <= $n then . else .[0:$n] , (.[$n:] | n) end;
+  n;
+
+def lpad($len): tostring | ($len - length) as $l | (" " * $l)[:$l] + .;
+
+def center(width):
+  tostring
+  | length as $l
+  | ((width - $l)/2 | floor) as $k
+  | (" " * $k) + . + (" " * (width - ($k+$l)));

Task/Calendar/Jq/calendar-2.jq

@@ -0,0 +1,56 @@
+def weekdaynames: ["Su", "Mo","Tu", "We", "Th", "Fr", "Sa"];
+
+# q.v. weekday
+# Output the integer index of weekdaynames, i.e. Sunday is 0
+def dayofweek($year; $month; $day):
+  "\($year)-\($month)-\($day)" | strptime("%Y-%m-%d") | .[-2];
+
+def isLeapYear(y):
+   y%4 == 0 and ((y%100 != 0) or (y%400 == 0));
+
+# January is 1
+def monthLength($y; $m):
+  def __diy: [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365];
+  def __diy2: [0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366];
+
+  if isLeapYear($y)
+  then __diy2[$m] - __diy2[$m-1]
+  else __diy[$m] - __diy[$m-1]
+  end;
+
+def calendar(year):
+  def snoopy: "🐶";
+  def months: [
+        "January", "February", "March", "April", "May", "June",
+        "July", "August", "September", "October", "November", "December" ];
+  (weekdaynames | join(" ")) as $days
+  # $chunk is a list of three months in group number $c
+  | def printRow($chunk; $c):
+    # The line of month names:
+    (" " + ($chunk | map(center(20)) | join("     "))),
+    # The line of weekday names
+    (" " + ([range(0;3)| $days] | join("     "))),
+    # The body of the calendar
+    (   [ dayofweek(year; $c*3 + 1; 1),
+          dayofweek(year; $c*3 + 2; 1),
+          dayofweek(year; $c*3 + 3; 1)] as $first
+      | [ monthLength(year; $c*3 + 1),
+          monthLength(year; $c*3 + 2),
+          monthLength(year; $c*3 + 3) ] as $mlen
+      # Print up to 6 lines
+      | range(0;6) as $i
+      | reduce range(0;3) as $j ("";
+            (1 + (7 * $i) - $first[$j]) as $start
+            | (reduce range($start; $start+7) as $k (.;
+                   if ($k >= 1 and $k <= $mlen[$j])
+                   then . + ($k|lpad(3))
+                   else . + "   "
+                   end )  +  "    " ) )
+        ),
+	"";
+
+    (snoopy, "--- \(year) ---" | center(72)),
+    ( [months|nwise(3)] as $chunks
+      | range(0;3) | printRow( $chunks[.]; .) );
+
+calendar(1969)

Task/Calendar/Julia/calendar.julia

@@ -0,0 +1,64 @@
+using Dates
+
+const pagesizes = Dict( "lpr" => [132, 66], "tn3270" => [80, 43])
+
+pagefit(prn) = haskey(pagesizes, prn) ?
+    [div(pagesizes[prn][1], 22), div(pagesizes[prn][2], 12)] : [1, 1]
+pagecols(prn) = haskey(pagesizes, prn) ? pagesizes[prn][1] : 20
+
+function centerobject(x, cols)
+    content = string(x)
+    rpad(lpad(content, div(cols + length(content), 2)), cols)
+end
+
+function ljustlines(x, cols)
+    arr = Vector{String}()
+    for s in split(x, "\n")
+        push!(arr, rpad(s, cols)[1:cols])
+    end
+    join(arr, "\n")
+end
+
+function formatmonth(yr, mo)
+    dt = Date("$yr-$mo-01")
+    dayofweekfirst = dayofweek(dt)
+    numweeklines = 1
+    str = centerobject(monthname(dt), 20) * "\nMo Tu We Th Fr Sa Su\n"
+    str *= " " ^ (3 * (dayofweekfirst - 1)) * lpad(string(1), 2)
+    for i = 2:daysinmonth(dt)
+        if (i + dayofweekfirst + 5) % 7 == 0
+            str *= "\n" * lpad(i, 2)
+            numweeklines += 1
+        else
+            str *= lpad(string(i), 3)
+        end
+    end
+    str *= numweeklines < 6 ? "\n\n\n" : "\n\n"
+    ljustlines(str, 20)
+end
+
+function formatyear(displayyear, printertype)
+    calmonths = [formatmonth(displayyear, mo) for mo in 1:12]
+    columns = pagecols(printertype)
+    monthsperline = pagefit(printertype)[1]
+    joinspaces = max( (monthsperline > 1) ?
+        div(columns - monthsperline * 20, monthsperline - 1) : 1, 1)
+    str = "\n" * centerobject(displayyear, columns) * "\n"
+    monthcal = [split(formatmonth(displayyear, i), "\n") for i in 1:12]
+    for i in 1:monthsperline:length(calmonths) - 1
+        for j in 1:length(monthcal[1])
+            monthlines = map(x->monthcal[x][j], i:i + monthsperline - 1)
+            str *= rpad(join(monthlines, " " ^ joinspaces), columns) * "\n"
+        end
+        str *= "\n"
+    end
+    str
+end
+
+function lineprintcalendar(years)
+    for year in years, printer in keys(pagesizes)
+        println(formatyear(year, printer))
+    end
+end
+
+lineprintcalendar(1969)

Task/Calendar/Kotlin/calendar.kotlin

@@ -0,0 +1,55 @@
+import java.io.PrintStream
+import java.text.DateFormatSymbols
+import java.text.MessageFormat
+import java.util.Calendar
+import java.util.GregorianCalendar
+import java.util.Locale
+
+internal fun PrintStream.printCalendar(year: Int, nCols: Byte, locale: Locale?) {
+    if (nCols < 1 || nCols > 12)
+        throw IllegalArgumentException("Illegal column width.")
+    val w = nCols * 24
+    val nRows = Math.ceil(12.0 / nCols).toInt()
+
+    val date = GregorianCalendar(year, 0, 1)
+    var offs = date.get(Calendar.DAY_OF_WEEK) - 1
+
+    val days = DateFormatSymbols(locale).shortWeekdays.slice(1..7).map { it.slice(0..1) }.joinToString(" ", " ")
+    val mons = Array(12) { Array(8) { "" } }
+    DateFormatSymbols(locale).months.slice(0..11).forEachIndexed { m, name ->
+        val len = 11 + name.length / 2
+        val format = MessageFormat.format("%{0}s%{1}s", len, 21 - len)
+        mons[m][0] = String.format(format, name, "")
+        mons[m][1] = days
+        val dim = date.getActualMaximum(Calendar.DAY_OF_MONTH)
+        for (d in 1..42) {
+            val isDay = d > offs && d <= offs + dim
+            val entry = if (isDay) String.format(" %2s", d - offs) else "   "
+            if (d % 7 == 1)
+                mons[m][2 + (d - 1) / 7] = entry
+            else
+                mons[m][2 + (d - 1) / 7] += entry
+        }
+        offs = (offs + dim) % 7
+        date.add(Calendar.MONTH, 1)
+    }
+
+    printf("%" + (w / 2 + 10) + "s%n", "[Snoopy Picture]")
+    printf("%" + (w / 2 + 4) + "s%n%n", year)
+
+    for (r in 0 until nRows) {
+        for (i in 0..7) {
+            var c = r * nCols
+            while (c < (r + 1) * nCols && c < 12) {
+                printf("   %s", mons[c][i])
+                c++
+            }
+            println()
+        }
+        println()
+    }
+}
+
+fun main(args: Array<String>) {
+    System.out.printCalendar(1969, 3, Locale.US)
+}

Task/Calendar/Liberty-BASIC/calendar.basic

@@ -0,0 +1,59 @@
+rem Adapted from LB examples included with software
+[start]
+    prompt "Enter year(yyyy)?";year
+    if year<1900 then notice "1900 or later":goto [start]
+    ax=1:gx=8:ay=3:gy=10
+    locate 52,1:print year
+    for mr = 0 to 3
+        for mc = 0 to 2
+            mt=mt+1
+            aDate$ = str$(mt)+"/01/"+str$(year)
+            px = ax+mc*gx
+            py = ay+mr*gy
+            gosub [printout]
+        next mc
+    next mr
+    gosub [snoopy]
+end
+
+[printout]
+    locate 4*px-3+int((30-len(monthname$(aDate$)))/2),py
+    print monthname$(aDate$)
+    FirstDay=date$(word$(aDate$,1,"/")+"/1/"+word$(aDate$,3,"/"))
+    LastDay$=date$(date$(word$(date$(FirstDay+32),1,"/")+"/1/"+word$(date$(FirstDay+32),3,"/"))-1)
+    dow=val(word$("3 4 5 x 6 7 x 1 2",int((FirstDay/7-int(FirstDay/7))*10)+1))
+    locate px*4-3, py+1
+    print " Su Mo  Tu  We  Th  Fr  Sa"
+    for i=1 to val(mid$(LastDay$,4,2))
+        y=int((i+dow-2)/7)
+        x=px+(i+dow-2)-y*7
+        x=4*x
+        locate x-4,py+y+2
+        print using("###",i)
+    next i
+return
+
+[snoopy]
+    locate ax, ay+4*gy
+    print space$(4*gx);"           ,-~~-.___."
+    print space$(4*gx);"          / ()=(()   \"
+    print space$(4*gx);"         (   (        0"
+    print space$(4*gx);"          \._\, ,----'"
+    print space$(4*gx);"     ##XXXxxxxxxx"
+    print space$(4*gx);"            /  ---'~;"
+    print space$(4*gx);"           /    /~|-"
+    print space$(4*gx);"    _____=(   ~~  |______ "
+    print space$(4*gx);"   /_____________________\ "
+    print space$(4*gx);"  /_______________________\"
+    print space$(4*gx);" /_________________________\"
+    print space$(4*gx);"/___________________________\"
+    print space$(4*gx);"   |____________________|"
+    print space$(4*gx);"   |____________________|"
+    print space$(4*gx);"   |____________________|"
+    print space$(4*gx);"   |                    |"
+return
+
+function monthname$(aDate$)
+    month=val(aDate$)
+    monthname$=word$("January February March April May June July August September October November December",month)
+end function

Task/Calendar/Lingo/calendar-1.lingo

@@ -0,0 +1,57 @@
+----------------------------------------
+-- @desc      Class "Calendar"
+-- @file      parent script "Calendar"
+----------------------------------------
+property _months
+property _weekdayStr
+property _refDateObj
+property _year
+property _calStr
+
+on new (me)
+  me._months = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"]
+  me._weekdayStr = "Mo Tu We Th Fr Sa Su"
+  me._refDateObj = date(1905,1,2)
+  return me
+end
+
+on make (me, year)
+  me._year = year
+  me._calStr = ""
+  -- prefill cal string with spaces
+  emptyLine = bytearray(68,32).readRawString(68)&RETURN
+  repeat with i = 1 to 38
+    put emptyLine after _calStr
+  end repeat
+  me._write (string(year), 32, 1)
+  repeat with i = 1 to 12
+    me._writeMonth(i)
+  end repeat
+  return me._calStr
+end
+
+on _writeMonth (me, monthNum)
+  xOffset = (monthNum-1) mod 3 * 24
+  yOffset = (monthNum-1)/3 * 9 + 2
+  pre = (20 - me._months[monthNum].length)/2
+  me._write(me._months[monthNum], 1+xOffset+pre, 1+yOffset)
+  me._write(me._weekdayStr, 1+xOffset, 2+yOffset)
+  y = 3
+  x = ((date(me._year, monthNum, 1) - me._refDateObj) mod 7)+1
+  repeat with i = 1 to 31
+    if date(me._year, monthNum, i).month<>monthNum then exit repeat
+    dayStr = string(i)
+    if i<10 then put " " before dayStr
+    me._write(dayStr, x*3-2+xOffset, y+yOffset)
+    if x=7 then
+      y = y+1
+      x = 1
+    else
+      x = x+1
+    end if
+  end repeat
+end
+
+on _write (me, str, x, y)
+  put str into char x to x+str.length-1 of line y of _calStr
+end

Task/Calendar/Lingo/calendar-2.lingo

@@ -0,0 +1,3 @@
+calObj = script("Calendar").new()
+calStr = calObj.make(1969)
+put calStr

Task/Calendar/Lua/calendar.lua

@@ -0,0 +1,63 @@
+function print_cal(year)
+  local months={"JANUARY","FEBRUARY","MARCH","APRIL","MAY","JUNE",
+                "JULY","AUGUST","SEPTEMBER","OCTOBER","NOVEMBER","DECEMBER"}
+  local daysTitle="MO TU WE TH FR SA SU"
+  local daysPerMonth={31,28,31,30,31,30,31,31,30,31,30,31}
+  local startday=((year-1)*365+math.floor((year-1)/4)-math.floor((year-1)/100)+math.floor((year-1)/400))%7
+  if year%4==0 and year%100~=0 or year%400==0 then
+    daysPerMonth[2]=29
+  end
+  local sep=5
+  local monthwidth=daysTitle:len()
+  local calwidth=3*monthwidth+2*sep
+
+  function center(str, width)
+    local fill1=math.floor((width-str:len())/2)
+    local fill2=width-str:len()-fill1
+    return string.rep(" ",fill1)..str..string.rep(" ",fill2)
+  end
+
+  function makeMonth(name, skip,days)
+    local cal={
+      center(name,monthwidth),
+      daysTitle
+    }
+    local curday=1-skip
+    while #cal<9 do
+      line={}
+      for i=1,7 do
+        if curday<1 or curday>days then
+          line[i]="  "
+        else
+          line[i]=string.format("%2d",curday)
+        end
+        curday=curday+1
+      end
+      cal[#cal+1]=table.concat(line," ")
+    end
+    return cal
+  end
+
+  local calendar={}
+  for i,month in ipairs(months) do
+    local dpm=daysPerMonth[i]
+    calendar[i]=makeMonth(month, startday, dpm)
+    startday=(startday+dpm)%7
+  end
+
+
+  print(center("[SNOOPY]",calwidth),"\n")
+  print(center("--- "..year.." ---",calwidth),"\n")
+
+  for q=0,3 do
+    for l=1,9 do
+      line={}
+      for m=1,3 do
+        line[m]=calendar[q*3+m][l]
+      end
+      print(table.concat(line,string.rep(" ",sep)))
+    end
+  end
+end
+
+print_cal(1969)

Task/Calendar/M2000-Interpreter/calendar.m2000

@@ -0,0 +1,67 @@
+Module Calendar (Year, LocaleId) {
+      Function GetMax(Year, Month) {
+            a=date(str$(Year)+"-"+str$(Month)+"-1")
+            max=32
+            do {
+                  max--
+                  m=val(str$(cdate(a,0,0,max), "m"))
+            } until m=Month
+             =max+1
+      }
+      Function SkipMo(Year, Month) {
+            a=date(str$(Year)+"-"+str$(Month)+"-1")
+            =(val(str$(a, "w"))-8) mod 7 +7
+      }
+      Function Title$(a$) {
+            =Ucase$(left$(a$,1))+Lcase$(Mid$(a$, 2))
+      }
+      locale LocaleId
+      Cursor 0,Height-1  ' last line, so each new line scroll all lines up
+      Print Over $(2), Year
+      Print
+      For j=0 to 3 {
+            Print
+            For i=1 to 3 {
+                  Month=i+j*3
+                  Print  Part @((i-1)*29-1), $(2,22), Title$(Ucase$(locale$(55+Month)))
+            }
+            Print
+            Dim Skip(1 to 3), Count(1 to 3), D(1 to 3)=1
+            For i=1 to 3 {
+                  Month=i+j*3
+                  if i>1 Then Print String$(" ",8);
+                  For k=42 to 48 :Print Title$(Ucase$(Left$(locale$(k),2)));" ";:Next k
+                  Skip(i)=SkipMo(Year, Month)
+                  Count(i)=GetMax(Year, Month)
+            }
+            Print
+            For i=1 to 3 {
+                      if i>1 Then Print String$(" ",8);
+                      For k=1 to 7 {
+                        skip(i)--
+                        if  skip(i)>0 Then Print "   "; :continue
+                        Count(i)--
+                        Print format$("{0::-2} ", d(i));
+                        d(i)++
+                  }
+            }
+            Print
+            Print @(0)
+            For m=1 to 5 {
+                  For i=1 to 3 {
+                        if i>1 Then Print String$(" ",8);
+                        For k=1 to 7 {
+                              Count(i)--
+                              if Count(i)<0 Then Print "   "; : Continue
+                              Print format$("{0::-2} ", d(i));
+                              d(i)++
+                        }
+                  }
+            Print
+            }
+      }
+}
+Form 80,43
+Calendar 1969, 1033 ' English
+k=Key$ ' wait key
+Calendar 2018, 1032  ' Greek

Task/Calendar/Mathematica/calendar-1.math

@@ -0,0 +1,49 @@
+DataGrid[
+  rowHeights:{__Integer},
+  colWidths:{__Integer},
+  spacings:{_Integer,_Integer},
+  borderWidths:{{_Integer,_Integer},{_Integer,_Integer}},
+  options_Association,
+  data:{__List?MatrixQ}]:=
+  With[
+    (*Need to make sure we have sensible defaults for the decoration options.*)
+    {alignment=Lookup[options,"alignment",{0,0}],
+     background=Lookup[options,"background"," "],
+     dividers=Lookup[options,"dividers",{" "," "," "}],
+     border=Lookup[options,"border"," "],
+     dims={Length[rowHeights],Length[colWidths]}},
+    (*Pad the data so that it will fit into the specified rectangle (list of lists).*)
+    With[{augmentedData=PadRight[data,Times@@dims,{{{background}}}]},
+      (*Create a matrix of dimensions based on desired rectangle. Once we have a matrix of cells we can "thread" these two matrices and use that data to coerce each cell into its final dimensions.*)
+      With[{cellDims=ArrayReshape[Outer[List,rowHeights,colWidths],{Times@@dims,2}]},
+        (*MatrixAlign, defined below, rescales and aligns each cell's data.*)
+        With[{undecoratedGrid=Partition[MapThread[MatrixAlign[alignment,#1,background][#2]&, {cellDims,augmentedData}],dims[[2]]]},
+          (*Add the spacing to each row.*)
+          With[{dividedRows=MapThread[Transpose[Riffle[#2,{ConstantArray[dividers[[2]],{#1,spacings[[2]]}]},{2,-2,2}]]&, {rowHeights,undecoratedGrid}]},
+            (*Add the spacing between rows.*)
+            With[{dividedColumn=Riffle[dividedRows,{Transpose[Riffle[ConstantArray[dividers[[1]],{spacings[[1]],#}]&/@colWidths,{ConstantArray[dividers[[3]],spacings]},{2,-2,2}]]},{2,-2,2}]},
+              (*Assemble all cell rows into actual character rows. We now have one large matrix.*)
+              With[{dividedGrid=Catenate[Map[Flatten,dividedColumn,{2}]]},
+                (*Add borders.*)
+                ArrayPad[dividedGrid,borderWidths,border]]]]]]]];
+
+DataGrid[dims:{_Integer,_Integer},spacings_,borderWidths_,options_,data:{__List?MatrixQ}]:=
+(*Calculate the max height for each row and max width for each column, and then just call the previous DataGrid function above.*)
+  With[
+    {rowHeights=Flatten@BlockMap[Max[Part[#,All,All,1]]&,ArrayReshape[Dimensions/@data,Append[dims,2],1],{1,dims[[2]]}],
+     colWidths=Flatten@BlockMap[Max[Part[#,All,All,2]]&,ArrayReshape[Dimensions/@data,Append[dims,2],1],{dims[[1]],1}]},
+    DataGrid[rowHeights,colWidths,spacings,borderWidths,options,data]];
+
+(*This could probably be simplified, but I like having all of the aligment options explicit and separate for testability.*)
+MatrixAlign[{-1,-1},dims_,pad_]:=PadRight[#,dims,pad]&;
+MatrixAlign[{-1,0},dims_,pad_]:=PadRight[CenterArray[#,{Dimensions[#][[1]],dims[[2]]},pad],dims,pad]&;
+MatrixAlign[{-1,1},dims_,pad_]:=PadRight[PadLeft[#,{Dimensions[#][[1]],dims[[2]]},pad],dims,pad]&;
+MatrixAlign[{0,-1},dims_,pad_]:=CenterArray[PadRight[#,{Dimensions[#][[1]],dims[[2]]},pad],dims,pad]&;
+MatrixAlign[{0,0},dims_,pad_]:=CenterArray[#,dims,pad]&;
+MatrixAlign[{0,1},dims_,pad_]:=CenterArray[PadLeft[#,{Dimensions[#][[1]],dims[[2]]},pad],dims,pad]&;
+MatrixAlign[{1,-1},dims_,pad_]:=PadLeft[PadRight[#,{Dimensions[#][[1]],dims[[2]]},pad],dims,pad]&;
+MatrixAlign[{1,0},dims_,pad_]:=PadLeft[CenterArray[#,{Dimensions[#][[1]],dims[[2]]},pad],dims,pad]&;
+MatrixAlign[{1,1},dims_,pad_]:=PadLeft[#,dims,pad]&;
+
+(*While the grid functions make no assumptions about the format of the data, we will be using them with string/character data, and we will eventually want to output a calendar as a single large string. AsString gives us a standard method for transforming a matrix of characters into a string with rows delimited by newlines.*)
+AsString[matrix_List?MatrixQ]:=StringRiffle[matrix,"\n",""];

Task/Calendar/Mathematica/calendar-10.math

@@ -0,0 +1,2 @@
+(*Choose a best fit for our 1969 calendar data on 80 character wide display.*)
+WidestFitDimensions[80,4,{0,0},MonthGrids1969]

Task/Calendar/Mathematica/calendar-11.math

@@ -0,0 +1,2 @@
+(*Choose a best fit for our 1969 calendar data on 132 character wide display.*)
+WidestFitDimensions[132,4,{0,0},MonthGrids1969]

Task/Calendar/Mathematica/calendar-12.math

@@ -0,0 +1,2 @@
+(*Can we fit into a 20-character wide display?*)
+WidestFitDimensions[20,4,{0,0},MonthGrids1969]

Task/Calendar/Mathematica/calendar-2.math

@@ -0,0 +1,9 @@
+DataA={{"A"}};
+GridA = DataGrid[{2},{5},{0,0},{{1,1},{1,1}},<|"border"->"*","alignment"->{1,-1}|>,{DataA}];
+DataB = {{"B"},{"B"}};
+GridB =
+  DataGrid[{4,3},{4,8},{2,3},{{0,0},{0,0}},<|"background"->".","alignment"->{0,1},"dividers"->{"-","|","+"}|>,{DataB,DataB,DataB}];
+GridC =
+  DataGrid[{2,3},{2,3},{{0,1},{2,3}},<|"border"->"@","alignment"->{0,0},"dividers"->{"/","/","/"}|>,{GridA,GridB,GridA,GridB,GridA}];
+
+DataGrid[{2,3},{2,12},{{0,0},{0,0}},<||>,{{{"A"}},{{"B"}},{{"C"}},GridA,GridB,GridC}]//AsString

Task/Calendar/Mathematica/calendar-3.math

@@ -0,0 +1,23 @@
+HeadedGrid[
+  finalSpacings:{_Integer,_Integer},
+  finalBorderWidths:{{_Integer,_Integer},{_Integer,_Integer}},
+  finalOptions_Association,
+  headerCellGridder_Function,
+  rawHeaders:{__String},
+  dataCellGridder_Function,
+  rawData:{__String}]:=
+  With[
+    {finalDims={Ceiling[(Length@rawData+Length@rawHeaders)/Length@rawHeaders],Length@rawHeaders},
+     headerCells=headerCellGridder/@List/@List/@Characters[rawHeaders],
+     dataCells=dataCellGridder/@List/@List/@Characters[rawData]},
+    DataGrid[finalDims,finalSpacings,finalBorderWidths,finalOptions,Join[headerCells,dataCells]]];
+
+(*An example with a few decorations:*)
+HeadedGrid[
+  {1,1},
+  {{1,1},{1,1}},
+  <|"dividers"->{"-","|","+"},"border"->"*"|>,
+  DataGrid[{3},{6},{0,0},{{0,0},{0,0}},<|"background"->"-"|>,#]&,
+  {"Su","Mo","Tu","We","Th","Fr","Sa"},
+  DataGrid[{3},{4},{0,0},{{0,0},{0,0}},<|"alignment"->{-1,1}|>,#]&,
+  ToString/@Range[31]]//AsString

Task/Calendar/Mathematica/calendar-4.math

@@ -0,0 +1,26 @@
+MonthGrid[
+  finalSpacings:{_Integer,_Integer},
+  finalBorderWidths:{{_Integer,_Integer},{_Integer,_Integer}},
+  finalOptions_Association,
+  titleGridder_Function,
+  monthName_String,
+  monthSpacings:{_Integer,_Integer},
+  monthBorderWidths:{{_Integer,_Integer},{_Integer,_Integer}},
+  monthOptions_Association,
+  headerCellGridder_Function,
+  weekdayNames:{__String},
+  dayCellGridder_Function,
+  dayOffset_Integer,
+  days:{__String}]:=
+  DataGrid[{2,1},finalSpacings,finalBorderWidths,finalOptions,
+    {titleGridder[List/@List/@Characters[monthName]],
+    HeadedGrid[monthSpacings,monthBorderWidths,monthOptions,headerCellGridder,weekdayNames,dayCellGridder,ArrayPad[days,{dayOffset,0},""]]}];
+
+(*A compact example:*)
+MonthGrid[{0, 0}, {{0, 0}, {0, 0}}, <||>,
+  DataGrid[{1, Length@#}, {0, 1}, {{1, 1}, {0, 0}}, <||>,ToUpperCase@#] &,
+  "September", {0, 1}, {{0, 0}, {0, 0}}, <||>,
+  DataGrid[{1}, {2}, {0, 0}, {{0, 0}, {0, 0}}, <||>, #] &,
+  {"Su", "Mo", "Tu", "We", "Th", "Fr", "Sa"},
+  DataGrid[{1}, {2}, {0, 0}, {{0, 0}, {0, 0}}, <|"alignment" -> {-1, 1}|>, #] &,
+  2, ToString /@ Range[31]]//AsString

Task/Calendar/Mathematica/calendar-5.math

@@ -0,0 +1,12 @@
+FractalChars[rasterSize_,font_,char_String/;1==StringLength[char]]:=
+  ReplaceAll[ImageData[ImageCrop[Binarize[Rasterize[Style[char,FontFamily->font],RasterSize->rasterSize]]]],{1->" ",0->char}];
+FractalChars[rasterSize_,font_,word_String]:=FractalChars[rasterSize,font,#]&/@Characters[word];
+
+(*And here's the convenience function that ultimately calls DataGrid.*)
+BannerGrid[finalSpacings_,finalBorderWidths_,finalOptions_,charGridder_Function,rasterSize_,text_String]:=
+With[
+  {charData=FractalChars[rasterSize,"Courier",text]},
+  DataGrid[{1,StringLength@text},finalSpacings,finalBorderWidths,finalOptions,charGridder/@List/@charData]];
+
+(*An example banner.*)
+BannerGrid[{0,5},{{1,1},{0,0}},<|"border"->"X"|>,DataGrid[{1,1},{0,0},{{1,1},{0,0}},<||>,#]&,20,"1969"]//AsString

Task/Calendar/Mathematica/calendar-6.math

@@ -0,0 +1,9 @@
+(*Mathematica makes it easy to get month names and day names for several standard calendars.*)
+MonthNames[]:=MonthNames["Gregorian"];
+MonthNames[calType_]:=Lookup[CalendarData[calType,"PropertyAssociation"],"MonthNames"];
+
+WeekdayNames[]:=WeekdayNames["Gregorian"];
+WeekdayNames[calType_]:=Lookup[CalendarData[calType,"PropertyAssociation"],"DayNames"];
+
+(*Since month boundaries don't align with week boundaries on most calendars, we need to pad month data with empty cells. I was tempted to create a function that would generate offsets for a given year on a given calendar, but even that required too many decisions on the part of the calendar maker to be feasible. So, I removed all of the calendar semantics. If you provide the fixed small group length (week length), the initial offset, and the list of the large group lengths (month lengths), this function will give you the offsets you need for each large group (month).*)
+Offsets[groupLength_,firstOffset_,lengths_List]:=FoldPairList[{#1,Mod[#1+#2,groupLength]}&,firstOffset,lengths];

Task/Calendar/Mathematica/calendar-7.math

@@ -0,0 +1,23 @@
+Data1969=GroupBy[Most[DateRange[DateObject[{1969,1,1}],DateObject[{1+1969,1,1}]]],DateValue[#,"MonthName"]&];
+InitialOffset1969=QuantityMagnitude[DateDifference[PreviousDate[DateObject[{1969,1,1}],Sunday],DateObject[{1969,1,1}]]];
+MonthLengths1969=Length/@Values[Data1969];
+Offsets1969=Offsets[7,InitialOffset1969,MonthLengths1969];
+MonthNames1969=Keys@Data1969;
+
+YearBanner1969=BannerGrid[{0,0},{{1,1},{0,0}},<|"border"->"X"|>,DataGrid[{1,1},{1,1},{{1,1},{5,5}},<||>,#]&,13,"1969"];
+
+MonthGrids1969=
+  With[
+    {monthNameGridder=DataGrid[{1,Length@#},{0,1},{{1,1},{0,0}},<||>,ToUpperCase@#]&,
+     dayNameGridder=DataGrid[{1},{2},{0,0},{{0,0},{0,0}},<|"alignment"->{0,-1}|>,#]&,
+     dayGridder=DataGrid[{1},{2},{0,0},{{0,0},{0,0}},<|"alignment"->{-1,1}|>,#]&},
+    With[
+      {monthGridder=
+         MonthGrid[{0,0},{{0,0},{0,0}},<||>,monthNameGridder,#1,
+         {0,1},{{0,0},{0,0}},<||>,dayNameGridder,WeekdayNames[],
+         dayGridder,#2,#3]&},
+      MapThread[monthGridder,{MonthNames1969,Offsets1969,Map[ToString,Range/@MonthLengths1969,{2}]}]]];
+
+MonthsGrid1969=DataGrid[{3,4},{1,4},{{0,0},{0,0}},<||>,MonthGrids1969];
+
+DataGrid[{2,1},{2,0},{{0,0},{0,0}},<||>,{YearBanner1969,MonthsGrid1969}]//AsString

Task/Calendar/Mathematica/calendar-8.math

@@ -0,0 +1,30 @@
+Dates1582France=
+  Join[
+    DateRange[DateObject[{1582,1,1},CalendarType->"Julian"],DateObject[{1582,10,4},CalendarType->"Julian"],CalendarType->"Julian"],
+    DateRange[DateObject[{1582,10,15}],DateObject[{1582,12,31}]]];
+Data1582France=GroupBy[Dates1582France,DateValue[#,"MonthName"]&];
+InitialOffset1582France=
+  QuantityMagnitude[DateDifference[
+    PreviousDate[CalendarConvert[DateObject[{1582,1,1},CalendarType->"Julian"],"Gregorian"],Sunday],
+    CalendarConvert[DateObject[{1582,1,1},CalendarType->"Julian"],"Gregorian"]]];
+MonthLengths1582France=Length/@Values[Data1582France];
+DatesByMonth1582France=Map[DateString[#,"DayShort"]&,Values[Data1582France],{2}];
+Offsets1582France=Offsets[7,InitialOffset1582France,MonthLengths1582France];
+MonthNames1582France=Keys@Data1582France;
+
+With[
+  {yearBanner=BannerGrid[{0,0},{{1,1},{0,0}},<|"border"->"X"|>,DataGrid[{1,1},{1,1},{{1,1},{5,5}},<||>,#]&,13,"1582"],
+   monthNameGridder=DataGrid[{1,Length@#},{0,1},{{1,1},{0,0}},<||>,ToUpperCase@#]&,
+   dayNameGridder=DataGrid[{1},{2},{0,0},{{0,0},{0,0}},<|"alignment"->{0,-1}|>,#]&,
+   dayGridder=DataGrid[{1},{2},{0,0},{{0,0},{0,0}},<|"alignment"->{-1,1}|>,#]&},
+  With[
+    {monthGridder=MonthGrid[{0,0},{{0,0},{0,0}},<||>,monthNameGridder,#1,{0,1},{{0,0},{0,0}},<||>,dayNameGridder,WeekdayNames[],dayGridder,#2,#3]&},
+    With[
+      {monthCells=MapThread[monthGridder,{MonthNames1582France,Offsets1582France,Map[ToString,Range/@MonthLengths1582France,{2}]}],
+       octoberCells=DataGrid[{1},{2},{0,0},Switch[#,"4"|"15",{{1,1},{1,1}},_,{{0,0},{0,0}}],<|"alignment"->{-1,1},"border"->"|","background"->Switch[#,"4"|"15","|",_," "]|>,{{Characters[#]}}]&/@ArrayPad[DatesByMonth1582France[[10]],{Offsets1582France[[10]],0},""]},
+      With[
+        {octoberGrid=
+           DataGrid[{2,1},{0,0},{{1,1},{1,1}},<|"border"->"*"|>,
+             {monthNameGridder[{{Characters[MonthNames1582France[[10]]]}}],
+              DataGrid[{1+Ceiling[Length@octoberCells/7],7},{0,1},{{0,0},{0,0}},<|"alignment"->{0,0}|>,octoberCells]}]},
+        DataGrid[{2,1},{2,0},{{0,0},{0,0}},<||>,{yearBanner,DataGrid[{3,4},{2,4},{{0,0},{0,0}},<|"alignment"->{-1,0}|>,ReplacePart[monthCells,10->octoberGrid]]}]]]]]//AsString

Task/Calendar/Mathematica/calendar-9.math

@@ -0,0 +1,17 @@
+WidestFitDimensions[
+  targetWidth_Integer,
+  columnSpacings_Integer,
+  leftRightBorderWidths:{_Integer,_Integer},
+  data:{__List?MatrixQ}]:=
+  With[
+    {widths=Last/@Dimensions/@data,
+     fullWidthOfRow=Total[ArrayPad[Riffle[#,columnSpacings],leftRightBorderWidths,1]]&},
+    With[
+      {fullWidthOfGrid=Max[fullWidthOfRow/@#]&},
+      With[
+        {isTooLarge=(targetWidth<fullWidthOfGrid[#])&},
+        With[
+          {bestFitGrid=
+             NestWhile[Partition[widths,-1+Last@Dimensions@#,-1+Last@Dimensions@#,{1,1},0]&,
+               {widths},isTooLarge[#]&,1,-1+Length@widths]},
+          <|"dimensions"->Dimensions@bestFitGrid,"width"->fullWidthOfGrid@bestFitGrid|>]]]];

Task/Calendar/Nim/calendar.nim

@@ -0,0 +1,38 @@
+import times
+import strformat
+
+proc printCalendar(year, nCols: int) =
+  var rows = 12 div nCols
+  var date = initDateTime(1, mJan, year, 0, 0, 0, utc())
+  if rows mod nCols != 0:
+    inc rows
+  var offs = getDayOfWeek(date.monthday, date.month, date.year).int
+  var mons: array[12, array[8, string]]
+  for m in 0..11:
+    mons[m][0] = &"{$date.month:^21}"
+    mons[m][1] = " Su Mo Tu We Th Fr Sa"
+    var dim = getDaysInMonth(date.month, date.year)
+    for d in 1..42:
+      var day = d > offs and d <= offs + dim
+      var str = if day: &" {d-offs:2}" else: "   "
+      mons[m][2 + (d - 1) div 7] &= str
+    offs = (offs + dim) mod 7
+    date = date + months(1)
+  var snoopyString, yearString: string
+  formatValue(snoopyString, "[Snoopy Picture]", "^" & $(nCols * 24 + 4))
+  formatValue(yearString, $year, "^" & $(nCols * 24 + 4))
+  echo snoopyString, "\n" , yearString, "\n"
+  for r in 0..<rows:
+    var s: array[8, string]
+    for c in 0..<nCols:
+      if r * nCols + c > 11:
+        break
+      for i, line in mons[r * nCols + c]:
+        s[i] &= &"   {line}"
+    for line in s:
+      if line == "":
+        break
+      echo line
+    echo ""
+
+printCalendar(1969, 3)

Task/Calendar/OCaml/calendar.ocaml

@@ -0,0 +1,196 @@
+#load "unix.cma"
+
+let lang = "en"  (* language: English *)
+
+let usage () =
+  Printf.printf "Usage:\n%s\n" Sys.argv.(0)
+
+let month_pattern =
+  [
+    [  0;  4;  8 ];
+    [  1;  5;  9 ];
+    [  2;  6; 10 ];
+    [  3;  7; 11 ];
+
+    (*
+    [  0;  1;  2;  3;  4;  5 ];
+    [  6;  7;  8;  9; 10; 11 ];
+
+    [  0;  1;  2;  3 ];
+    [  4;  5;  6;  7 ];
+    [  8;  9; 10; 11 ];
+    *)
+  ]
+
+let month_langs = [
+  "en", [|
+    "January"; "February"; "March"; "April";
+    "May"; "June"; "July"; "August"; "September";
+    "October"; "November"; "December";
+  |];
+  "fr", [|
+    "janvier"; "février"; "mars"; "avril"; "mai";
+    "juin"; "juillet"; "août"; "septembre";
+    "octobre"; "novembre"; "décembre";
+  |];
+]
+
+let days_lang = [
+  "en", [| "Monday"; "Tuesday"; "Wednesday";
+    "Thursday"; "Friday"; "Saturday"; "Sunday" |];
+  "fr", [| "lundi"; "mardi"; "mercredi";
+    "jeudi"; "vendredi"; "samedi"; "dimanche" |];
+]
+
+let titles_lang = [
+  "en", "( Snoopy's best pic )";
+  "fr", "( Le meilleur profil de Snoopy )";
+]
+
+let days = List.assoc lang days_lang
+let month = List.assoc lang month_langs
+let title = List.assoc lang titles_lang
+
+let monday_first = 6, [| 0; 1; 2; 3; 4; 5; 6 |]
+let sunday_first = 0, [| 6; 0; 1; 2; 3; 4; 5 |]
+
+let off, days_order = sunday_first
+let off, days_order = monday_first
+
+
+let shorten n s =
+  let len = String.length s in
+  if n >= len then s else
+    let n = if s.[n-1] = '\xC3' then n+1 else n in
+    if n >= len then s else
+      (String.sub s 0 n)
+
+
+let pad size c s =
+  let len = String.length s in
+  let n1 = (size - len) / 2 in
+  let n2 = size - len - n1 in
+  String.make n1 c ^ s ^
+  String.make n2 c
+
+
+let days = Array.map (shorten 2) days
+
+
+let indices ofs =
+  (ofs / 7, ofs mod 7)
+
+
+let t_same t1 t2 =
+  ( t1.Unix.tm_year = t2.Unix.tm_year &&
+    t1.Unix.tm_mon  = t2.Unix.tm_mon &&
+    t1.Unix.tm_mday = t2.Unix.tm_mday )
+
+
+let current_year () =
+  let t = Unix.localtime (Unix.time ()) in
+  (t.Unix.tm_year + 1900)
+
+
+let make_month t year month =
+  let empty_day = 0 in
+  let m = Array.make_matrix 6 7 empty_day in
+  let ofs = ref 0 in
+  for day = 1 to 31 do
+    let tm =
+      { t with
+        Unix.tm_year = year - 1900;
+        Unix.tm_mon = month;
+        Unix.tm_mday = day;
+      }
+    in
+    let _, this = Unix.mktime tm in
+    if !ofs = 0 then ofs := (this.Unix.tm_wday + off) mod 7;
+    if t_same this tm then
+      let i, j = indices !ofs in
+      m.(i).(j) <- day;
+    incr ofs;
+  done;
+  (m)
+
+
+let cal ~year =
+  let empty = [| [| |] |] in
+  let months = Array.make 12 empty in
+  let t = Unix.gmtime 0.0 in
+  for mon = 0 to 11 do
+    months.(mon) <- make_month t year mon;
+  done;
+  (months)
+
+
+let print_month_label mp =
+  List.iter (fun i ->
+    let mon = pad 20 ' ' month.(i) in
+    Printf.printf " %s " mon
+  ) mp;
+  print_newline ()
+
+
+let print_day_label mp =
+  List.iter (fun _ ->
+    Array.iter (fun i ->
+      Printf.printf " %s" days.(i)
+    ) days_order
+    ; print_string " "
+  ) mp;
+  print_newline ()
+
+
+let print_mon m mp =
+  print_month_label mp;
+  print_day_label mp;
+  for w = 0 to pred 6 do
+    print_string begin
+      String.concat " " begin
+        List.map (fun i ->
+          let b = Buffer.create 132 in
+          for d = 0 to pred 7 do
+            match m.(i).(w).(d) with
+            | 0 -> Buffer.add_string b "   "
+            | d -> Printf.kprintf (Buffer.add_string b) " %2d" d
+          done;
+          (Buffer.contents b)
+        ) mp
+      end
+    end
+    ; print_string "\n"
+  done
+
+
+let print_cal ~y:m =
+  List.iter (fun mon_row ->
+    print_mon m mon_row
+  ) month_pattern
+
+
+let print_header lbl =
+  let n = List.length (List.hd month_pattern) in
+  let year_lbl = pad (23*n-7) ' ' lbl in
+  Printf.printf " %s\n" year_lbl
+
+
+let print_calendar ~year =
+  print_header title;
+  print_header (string_of_int year);
+  print_cal (cal ~year)
+
+
+let () =
+  let args = List.tl (Array.to_list Sys.argv) in
+  match args with
+  | [] ->
+      let year = current_year () in
+      print_calendar ~year
+
+  | ["--year"; _year] ->
+      let year = int_of_string _year in
+      print_calendar ~year
+
+  | _ ->
+      usage ()

Task/Calendar/PL-I/calendar.pli

@@ -0,0 +1,51 @@
+calendar: procedure (year) options (main);
+   declare year character (4) varying;
+   declare (a, b, c) (0:5,0:6) character (3);
+   declare name_month(12) static character (9) varying initial (
+      'JANUARY', 'FEBRUARY', 'MARCH',     'APRIL',   'MAY',      'JUNE',
+      'JULY',    'AUGUST',   'SEPTEMBER', 'OCTOBER', 'NOVEMBER', 'DECEMBER');
+   declare i fixed;
+   declare (mm, mmp1, mmp2) pic '99';
+
+   put edit (center('CALENDAR FOR ' || YEAR, 67)) (a);
+   put skip (2);
+
+   do mm = 1 to 12 by 3;
+      mmp1 = mm + 1; mmp2 = mm + 2;
+      call prepare_month('01' || mm   || YEAR, a);
+      call prepare_month('01' || mmp1 || YEAR, b);
+      call prepare_month('01' || mmp2 || YEAR, c);
+
+      put skip edit (center(name_month(mm),   23),
+                     center(name_month(mmp1), 23),
+                     center(name_month(mmp2), 23) ) (a);
+      put skip edit ((3)'  M  T  W  T  F  S  S  ') (a);
+      do i = 0 to 5;
+         put skip edit (a(i,*), b(i,*), c(i,*)) (7 a, x(2));
+      end;
+   end;
+
+prepare_month: procedure (start, month);
+   declare month(0:5,0:6) character (3);
+   declare start character (8);
+   declare i pic 'ZZ9';
+   declare offset fixed;
+   declare (j, day) fixed binary (31);
+   declare (this_month, next_month, k) fixed binary;
+
+   day = days(start, 'DDMMYYYY');
+   offset = weekday(day) - 1;
+   if offset  = 0 then offset = 7;
+   month = '';
+   do j = day by 1;
+      this_month = substr(daystodate(j,   'DDMMYYYY'), 3, 2);
+      next_month = substr(daystodate(j+1, 'DDMMYYYY'), 3, 2);
+      if this_month^= next_month then leave;
+   end;
+   i = 1;
+   do k = offset-1 to offset+j-day-1;
+      month(k/7, mod(k,7)) = i; i = i + 1;
+   end;
+end prepare_month;
+
+end calendar;

Task/Calendar/Perl/calendar.pl

@@ -0,0 +1,33 @@
+#!/usr/bin/perl -l
+
+use strict; # https://rosettacode.org/wiki/Calendar
+use warnings;
+use Time::Local;
+
+my $year = shift // 1969;
+my $width = shift // 80;
+my $columns = int +($width + 2) / 22 or die "width too short at $width";
+print map { center($_, $width), "\n" } '<reserved for snoopy>', $year;
+my @months = qw( January February March April May June
+  July August September October November December );
+my @days = qw( 31 28 31 30 31 30 31 31 30 31 30 31 );
+(gmtime 86400 + timegm 1,1,1,28,1,$year)[3] == 29 and $days[1]++;
+my @blocks = map # block per month
+  {
+  my $m = center($months[$_], 20) . "\nSu Mo Tu We Th Fr Sa\n" .
+    "00 00 00 00 00 00 00\n" x 6;
+  $m =~ s/00/  / for 1 .. (gmtime timegm 1,1,1,1,$_,$year )[6]; # day of week
+  $m =~ s/00/ center($_, 2) /e for 1 .. $days[$_];
+  $m =~ s/00/  /g;
+  [ split /\n/, $m ]
+  } 0 .. 11;
+while( my @row = splice @blocks, 0, $columns ) # print by rows of months
+  {
+  print center(join('  ', map shift @$_, @row), $width) for 1 .. @{$row[0]};
+  }
+
+sub center
+  {
+  my ($string, $w) = @_;
+  sprintf "%${w}s", $string . ' ' x ($w - length($string) >> 1);
+  }

Task/Calendar/Phix/calendar.phix

@@ -0,0 +1,74 @@
+(phixonline)-->
+ <span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
+ <span style="color: #008080;">constant</span> <span style="color: #000000;">year</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1969</span>
+
+ <span style="color: #008080;">include</span> <span style="color: #000000;">builtins</span><span style="color: #0000FF;">\</span><span style="color: #004080;">timedate</span><span style="color: #0000FF;">.</span><span style="color: #000000;">e</span>
+
+ <span style="color: #008080;">function</span> <span style="color: #000000;">centre</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">width</span><span style="color: #0000FF;">)</span>
+     <span style="color: #004080;">integer</span> <span style="color: #000000;">gap</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">width</span><span style="color: #0000FF;">-</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">),</span>
+             <span style="color: #000000;">left</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">(</span><span style="color: #000000;">gap</span><span style="color: #0000FF;">/</span><span style="color: #000000;">2</span><span style="color: #0000FF;">),</span>
+             <span style="color: #000000;">right</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">gap</span><span style="color: #0000FF;">-</span><span style="color: #000000;">left</span>
+     <span style="color: #008080;">return</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">left</span><span style="color: #0000FF;">)</span> <span style="color: #0000FF;">&</span> <span style="color: #000000;">s</span> <span style="color: #0000FF;">&</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">right</span><span style="color: #0000FF;">)</span>
+ <span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
+
+ <span style="color: #008080;">function</span> <span style="color: #000000;">one_month</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">year</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">month</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">bool</span> <span style="color: #000000;">sun_to_sat</span><span style="color: #0000FF;">)</span>
+     <span style="color: #004080;">string</span> <span style="color: #000000;">weekdays</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sun_to_sat</span><span style="color: #0000FF;">?</span><span style="color: #008000;">"Su Mo Tu We Th Fr Sa"</span>
+                                     <span style="color: #0000FF;">:</span><span style="color: #008000;">"Mo Tu We Th Fr Sa Su"</span><span style="color: #0000FF;">),</span>
+            <span style="color: #000000;">line</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">20</span><span style="color: #0000FF;">)</span>
+     <span style="color: #004080;">sequence</span> <span style="color: #000000;">ldm</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">adjust_timedate</span><span style="color: #0000FF;">(</span><span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #000000;">month</span><span style="color: #0000FF;">=</span><span style="color: #000000;">12</span><span style="color: #0000FF;">?{</span><span style="color: #000000;">year</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">}</span>
+                                                <span style="color: #0000FF;">:{</span><span style="color: #000000;">year</span><span style="color: #0000FF;">,</span><span style="color: #000000;">month</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">}),</span>
+                                    <span style="color: #7060A8;">timedelta</span><span style="color: #0000FF;">(</span><span style="color: #000000;">days</span><span style="color: #0000FF;">:=-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)),</span>
+              <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">centre</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">format_timedate</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ldm</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Mmmm"</span><span style="color: #0000FF;">),</span><span style="color: #000000;">20</span><span style="color: #0000FF;">),</span><span style="color: #000000;">weekdays</span><span style="color: #0000FF;">}</span>
+     <span style="color: #004080;">integer</span> <span style="color: #000000;">dow</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">day_of_week</span><span style="color: #0000FF;">(</span><span style="color: #000000;">year</span><span style="color: #0000FF;">,</span><span style="color: #000000;">month</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span>
+     <span style="color: #008080;">if</span> <span style="color: #000000;">sun_to_sat</span> <span style="color: #008080;">then</span> <span style="color: #000000;">dow</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">remainder</span><span style="color: #0000FF;">(</span><span style="color: #000000;">dow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">7</span><span style="color: #0000FF;">)+</span><span style="color: #000000;">1</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+     <span style="color: #004080;">integer</span> <span style="color: #000000;">lastday</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ldm</span><span style="color: #0000FF;">[</span><span style="color: #004600;">DT_DAY</span><span style="color: #0000FF;">],</span>
+             <span style="color: #000000;">p</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">dow</span><span style="color: #0000FF;">*</span><span style="color: #000000;">3</span><span style="color: #0000FF;">-</span><span style="color: #000000;">2</span>
+     <span style="color: #008080;">for</span> <span style="color: #000000;">d</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">lastday</span> <span style="color: #008080;">do</span>
+         <span style="color: #000000;">line</span><span style="color: #0000FF;">[</span><span style="color: #000000;">p</span><span style="color: #0000FF;">..</span><span style="color: #000000;">p</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sprintf</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"%2d"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">d</span><span style="color: #0000FF;">)</span>
+         <span style="color: #000000;">p</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">3</span>
+         <span style="color: #008080;">if</span> <span style="color: #000000;">dow</span><span style="color: #0000FF;">=</span><span style="color: #000000;">7</span> <span style="color: #008080;">or</span> <span style="color: #000000;">d</span><span style="color: #0000FF;">=</span><span style="color: #000000;">lastday</span> <span style="color: #008080;">then</span>
+             <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">res</span><span style="color: #0000FF;">,</span><span style="color: #000000;">line</span><span style="color: #0000FF;">)</span>
+             <span style="color: #000000;">line</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">20</span><span style="color: #0000FF;">)</span>
+             <span style="color: #000000;">dow</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
+             <span style="color: #000000;">p</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
+         <span style="color: #008080;">else</span>
+             <span style="color: #000000;">dow</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
+         <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+     <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+     <span style="color: #008080;">return</span> <span style="color: #000000;">res</span>
+ <span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
+
+ <span style="color: #008080;">procedure</span> <span style="color: #000000;">print_calendar</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">year</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">width</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">bool</span> <span style="color: #000000;">sun_to_sat</span><span style="color: #0000FF;">=</span><span style="color: #004600;">false</span><span style="color: #0000FF;">)</span>
+     <span style="color: #004080;">sequence</span> <span style="color: #000000;">months</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">12</span><span style="color: #0000FF;">)</span>
+     <span style="color: #004080;">integer</span> <span style="color: #000000;">wide</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">((</span><span style="color: #000000;">width</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span><span style="color: #0000FF;">)/</span><span style="color: #000000;">22</span><span style="color: #0000FF;">)</span>
+     <span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">centre</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"[Spot Reserved For Snoopy]"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">width</span><span style="color: #0000FF;">)&</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">)</span>
+     <span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">centre</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">sprintf</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"%d"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">year</span><span style="color: #0000FF;">),</span><span style="color: #000000;">width</span><span style="color: #0000FF;">)&</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">)</span>
+     <span style="color: #008080;">for</span> <span style="color: #000000;">month</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">12</span> <span style="color: #008080;">do</span>
+         <span style="color: #000000;">months</span><span style="color: #0000FF;">[</span><span style="color: #000000;">month</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">one_month</span><span style="color: #0000FF;">(</span><span style="color: #000000;">year</span><span style="color: #0000FF;">,</span><span style="color: #000000;">month</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sun_to_sat</span><span style="color: #0000FF;">)</span>
+     <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+     <span style="color: #008080;">for</span> <span style="color: #000000;">month</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">12</span> <span style="color: #008080;">by</span> <span style="color: #000000;">wide</span> <span style="color: #008080;">do</span>
+         <span style="color: #008080;">for</span> <span style="color: #000000;">k</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">9</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- (more than enough)</span>
+             <span style="color: #004080;">integer</span> <span style="color: #000000;">any</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
+             <span style="color: #004080;">string</span> <span style="color: #000000;">line</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span>
+             <span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">wide</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
+                 <span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
+                     <span style="color: #000000;">line</span> <span style="color: #0000FF;">&=</span> <span style="color: #008000;">"  "</span>
+                 <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+                 <span style="color: #008080;">if</span> <span style="color: #000000;">k</span><span style="color: #0000FF;">></span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">months</span><span style="color: #0000FF;">[</span><span style="color: #000000;">month</span><span style="color: #0000FF;">+</span><span style="color: #000000;">j</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">then</span>
+                     <span style="color: #000000;">line</span> <span style="color: #0000FF;">&=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">20</span><span style="color: #0000FF;">)</span>
+                 <span style="color: #008080;">else</span>
+                     <span style="color: #000000;">line</span> <span style="color: #0000FF;">&=</span> <span style="color: #000000;">months</span><span style="color: #0000FF;">[</span><span style="color: #000000;">month</span><span style="color: #0000FF;">+</span><span style="color: #000000;">j</span><span style="color: #0000FF;">][</span><span style="color: #000000;">k</span><span style="color: #0000FF;">]</span>
+                     <span style="color: #000000;">any</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
+                 <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+             <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+             <span style="color: #008080;">if</span> <span style="color: #000000;">any</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+             <span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">centre</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">,</span><span style="color: #000000;">width</span><span style="color: #0000FF;">)&</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">)</span>
+         <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+     <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+ <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
+
+ <span style="color: #000000;">print_calendar</span><span style="color: #0000FF;">(</span><span style="color: #000000;">year</span><span style="color: #0000FF;">,</span><span style="color: #000000;">80</span><span style="color: #0000FF;">)</span>
+ <span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"1234567890"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">8</span><span style="color: #0000FF;">),</span><span style="color: #008000;">""</span><span style="color: #0000FF;">)&</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">)</span>
+ <span style="color: #000000;">print_calendar</span><span style="color: #0000FF;">(</span><span style="color: #000000;">year</span><span style="color: #0000FF;">,</span><span style="color: #000000;">132</span><span style="color: #0000FF;">,</span><span style="color: #004600;">true</span><span style="color: #0000FF;">)</span>
+ <span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"1234567890"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">13</span><span style="color: #0000FF;">),</span><span style="color: #008000;">""</span><span style="color: #0000FF;">)&</span><span style="color: #008000;">"12\n"</span><span style="color: #0000FF;">)</span>
+<!--

Task/Calendar/Phixmonti/calendar.phixmonti

@@ -0,0 +1,120 @@
+include ..\Utilitys.pmt
+
+32 var space
+
+def bksp    /# -- backspace #/
+    8 tochar print
+enddef
+
+def floor
+    .5 + int
+enddef
+
+def center
+    tostr align
+enddef
+
+def startday    /# year -- day of the week of january 1 #/
+    1 - >ps
+    tps 365 * tps 4 / floor + tps 100 / floor - ps> 400 / floor + 7 mod
+enddef
+
+def bisiesto? /# year -- true if leap #/
+    dup 4 mod not over 100 mod and swap 400 mod not or
+enddef
+
+def snoopy
+    0 tcolor 15 bcolor
+    "snoopy.txt" "r" fopen var f
+
+    true
+    while
+        f fgets
+        dup -1 == if
+            drop
+            f fclose
+            false
+        else
+            print
+            true
+        endif
+    endwhile
+
+    15 tcolor 0 bcolor
+enddef
+
+( "JANUARY" "FEBRUARY" "MARCH" "APRIL" "MAY" "JUNE" "JULY" "AUGUST" "SEPTEMBER" "OCTOBER" "NOVEMBER" "DECEMBER" ) var months
+"MO TU WE TH FR SA SU" var daysTitle
+( 31 28 31 30 31 30 31 31 30 31 30 31 ) var daysPerMonth
+daysTitle len nip var monthwidth
+
+def makeMonth var days >ps
+    monthwidth center daysTitle 2 tolist
+
+    1 ps> - 1 + >ps
+
+    true
+    while
+      ( )
+      7 for drop
+        tps 1 < tps days > or if
+            " "
+        else
+            tps
+        endif
+        2 align 0 put
+        ps> 1 + >ps
+      endfor
+      0 put
+      len 8 <
+    endwhile
+    ps> drop
+enddef
+
+def print_cal >ps
+    tps bisiesto? if daysPerMonth 29 2 set var daysPerMonth endif
+    5 space over repeat var spaces
+
+    snoopy
+
+    3 monthwidth * swap 2 * +
+    "--- " tps tostr " ---" chain chain swap center ? nl
+
+    ps> startday var inicio
+
+    ( )
+
+    12 for >ps
+        months tps get nip inicio
+        daysPerMonth ps> get nip >ps
+        tps makeMonth 0 put
+        inicio ps> + 7 mod var inicio
+    endfor
+
+    ( 0 3 ) for var i
+        8 for var k
+            3 for var j
+                i 3 * j + get
+                k get
+                list? if
+                    10 tcolor
+                    len for
+                        get print " " print
+                    endfor
+                    drop
+                    bksp
+                else
+                    11 tcolor
+                    print
+                endif
+                drop
+                spaces print
+            endfor
+            nl
+        endfor
+        nl
+    endfor
+    drop
+enddef
+
+2020 print_cal

Task/Calendar/PicoLisp/calendar.l

@@ -0,0 +1,13 @@
+(de cal (Year)
+   (prinl "====== " Year " ======")
+   (for Dat (range (date Year 1 1) (date Year 12 31))
+      (let D (date Dat)
+         (tab (3 3 4 8)
+            (when (= 1 (caddr D))
+               (get *Mon (cadr D)) )
+            (caddr D)
+            (day Dat *Day)
+            (when (=0 (% (inc Dat) 7))
+               (pack "Week " (week Dat)) ) ) ) ) )
+
+(cal 1969)

Task/Calendar/Pike/calendar.pike

@@ -0,0 +1,119 @@
+#!/bin/env pike
+
+int main(int argc, array(string) argv)
+{
+    object cal = Calendar;
+    object year;
+    string region = "us";
+
+    array date = argv[1..];
+    if (sizeof(date) && objectp(Calendar[date[0]]) && Calendar[date[0]]->Day)
+    {
+        cal = Calendar[date[0]];
+        date = Array.shift(date)[1];
+    }
+
+    if (sizeof(date) && (int)date[0])
+    {
+        year = cal.Year((int)date[0]);
+        date = Array.shift(date)[1];
+    }
+
+    if (sizeof(date))
+        region = date[0];
+
+    if (!year)
+        year = cal.Year();
+
+    print_year(year, region);
+}
+
+array make_month(object month, int field_width, void|string region)
+{
+    array out =({});
+    mapping holidays = ([]);
+    object today = Calendar.Day();
+
+    if (region)
+        holidays = Calendar.Events.find_region(region)->scan_events(month);
+
+    array weekday_names =
+        sprintf("%*.*s", field_width, field_width, month->week()->days()->week_day_shortname()[*]);
+
+    out += ({ ({ month->month_name(), month->month_no(), month->year_name() }) });
+    out += ({ weekday_names });
+    out += showday(month->weeks()->days()[*][*], month, today, holidays, field_width);
+
+    out += ({ ({ " "*field_width })*sizeof(weekday_names) });
+
+    return out;
+}
+
+string print_month(object _month, void|int field_width, void|string region)
+{
+    if (!field_width)
+        field_width = 2;
+    array month = make_month(_month, field_width, region);
+    string out = "";
+
+    out += sprintf("%|*s\n", (field_width+1)*sizeof(month[1])-1, sprintf("%s", month[0][0]));
+    out += sprintf((month[1..][*]*" ")*"\n");
+    return out;
+}
+
+string print_year(object year, void|string region)
+{
+        array output = ({});
+        int day_width = 2;
+        int columns = Stdio.stdout.tcgetattr()->columns;
+        int month_width = sizeof(make_month(year->month(), day_width)[1]) * (day_width+1) - 1;
+        if (columns < month_width)
+            columns = month_width;
+
+        // try to find an optimal good looking solution to spread the months
+        // across the terminal width
+        // for the common calendar of 12 months this is easy but we need to
+        // account for caledars that have more than 12 months
+        float max_width = (float)((columns+2)/(month_width+2));
+        float max_height = ceil(year->number_of_months()/max_width);
+        float w = max_width;
+
+        while(ceil(year->number_of_months()/(w-1)) == max_height)
+            w--;
+
+        foreach(print_month(year->months()[*], day_width, region)/w;; array row)
+        {
+            array rows = row[*]/"\n";
+            int l = max(@sizeof(rows[*]));
+            foreach(rows; int i;)
+            {
+                // the last line of each month is an empty line.
+                // repeat the line as many times as needed to make the months equally long
+                rows[i]+=({ rows[i][-1] })*(l-sizeof(rows[i]));
+            }
+            rows = Array.transpose(rows);
+            output += rows[*]*"  ";
+        }
+        write("%*|s\n", sizeof(output[1]), year->format_nice());
+        write(output * "\n");
+        write("\n");
+}
+
+string showday(object day, object month, object today, mapping holidays, int field_width)
+{
+    string dayname;
+    if (day->month() == month)
+    {
+        dayname = (string)day->month_day();
+        dayname = " "*(sizeof((string)month->number_of_days())-sizeof(dayname))+dayname;
+        if (day == today)
+            dayname = sprintf("%|*.*s", field_width, field_width, dayname);
+        else
+            dayname = sprintf("%|*.*s", field_width, field_width, dayname);
+        if (holidays[day])
+            dayname = sprintf("%|s", dayname);
+    }
+    else
+        dayname = " "*field_width;
+    return dayname;
+}

Task/Calendar/PowerShell/calendar.psh

@@ -0,0 +1,36 @@
+Param([int]$Year = 1969)
+Begin {
+    $COL_WIDTH = 21
+    $COLS = 3
+    $MONTH_COUNT = 12
+    $MONTH_LINES = 9
+
+    Function CenterStr([string]$s, [int]$lineSize) {
+        $padSize = [int](($lineSize - $s.Length) / 2)
+        ($(if ($padSize -gt 0) { ' ' * $padSize } else { '' }) + $s).PadRight($lineSize,' ')
+    }
+
+    Function MonthLines([int]$month) {
+        $dt = [System.DateTime]::new($Year, $month, 1)
+        $line = CenterStr $dt.ToString("MMMM") $COL_WIDTH
+        $line += 'Su Mo Tu We Th Fr Sa'
+        $line += $('   ' * $dt.DayOfWeek.value__)
+        $line += (-join ($(1..$($dt.AddMonths(1).AddDays(-1).Day)) | %{ $("" + $_).PadLeft(3) }))
+        $line = $line.PadRight($MONTH_LINES * $COL_WIDTH)
+        New-Object –TypeName PSObject –Prop(@{
+            'Lines'=(0..($MONTH_LINES - 1)) | %{ $_ * $COL_WIDTH } | %{ -join $line[$_..($_ + $COL_WIDTH - 1)] }
+            'Dt'=$dt})
+    }
+}
+Process {
+    Write-Output (CenterStr $Year ($COL_WIDTH * $COLS + 4))
+    $(0..($MONTH_COUNT / $COLS - 1)) | %{
+        $fm = $_ * $COLS
+        $monthNums = $fm..($fm + $COLS - 1) | %{ $_ + 1 }
+        $months = $monthNums | %{ MonthLines $_ }
+        $(0..($MONTH_LINES - 1)) | %{
+            $ml = $_
+            Write-Output $(-join ($(0..($COLS - 1)) | %{ $(if ($_ -eq 0) { '' } else {'  '}) + $months[$_].Lines[$ml] }))
+        }
+    }
+}

Task/Calendar/Prolog/calendar.pro

@@ -0,0 +1,94 @@
+% Write out the calender, because format can actually span multiple lines, it is easier
+% to write out the static parts in place and insert the generated parts into that format.
+write_calendar(Year) :-
+	month_x3_format(Year, 1, 2, 3, F1_3),
+	month_x3_format(Year, 4, 5, 6, F4_6),
+	month_x3_format(Year, 7, 8, 9, F7_9),
+	month_x3_format(Year, 10, 11, 12, F10_12),
+	
+	format('
+
+                                      ~w
+
+            January                  February                   March
+      Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa
+~w
+
+             April                     May                      June
+      Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa
+~w
+
+              July                    August                  September
+      Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa
+~w
+
+            October                  November                 December
+      Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa
+~w	
+', [Year, F1_3, F4_6, F7_9, F10_12]), !.
+
+% Generate the data for a row of months and then create an atom one row at a time
+% for all of the months.
+month_x3_format(Year, M1, M2, M3, F) :-
+	calc_month_rows(Year, M1, M1r),
+	calc_month_rows(Year, M2, M2r),
+	calc_month_rows(Year, M3, M3r),
+	month_x3_format(M1r, M2r, M3r, F).
+	
+month_x3_format(M1, M2, M3, '') :- maplist(=('   '), M1), maplist(=('   '), M2), maplist(=('   '), M3).
+month_x3_format(M1, M2, M3, F) :-
+		month_format('      ', M1, M1r, F1),
+		month_format(F1, M2, M2r, F2),
+		month_format(F2, M3, M3r, F3),
+		atom_concat(F3, '\n', F4),
+		month_x3_format(M1r, M2r, M3r, Fr),
+		atom_concat(F4, Fr, F).
+	
+month_format(Orig, [Su,Mo,Tu,We,Th,Fr,Sa|R], R, F) :-
+	maplist(day_format, [Su,Mo,Tu,We,Th,Fr,Sa], Formatted),
+	format(atom(F2), '~w~w~w~w~w~w~w    ', Formatted),
+	atom_concat(Orig, F2, F).
+
+day_format('   ', '   ') :- !.
+day_format(D, F) :- D < 10, format(atom(F), '~w  ', D).
+day_format(D, F) :- D >= 10, format(atom(F), '~w ', D).
+
+% Calculate the days of a month, this is done by getting the first day of the month,
+% then offsetting that with spaces from the start and then adding 1-NumDaysinMonth and
+% finally spaces until the end. The maximum possible size is used and then truncated later.
+calc_month_rows(Year, Month, Result) :-
+	length(Result, 42), % max 6 rows of 7 days
+	month_days(Month, Year, DaysInMonth),
+	day_of_the_week(date(Year, Month, 1), FirstWeekDay),
+	day_offset(FirstWeekDay, Offset),
+	day_print_map(DaysInMonth, Offset, Result).
+
+day_print_map(DaysInMonth, 0, [1|R]) :-	
+	day_print_map2(DaysInMonth, 2, R).	
+day_print_map(DaysInMonth, Offset, ['   '|R]) :-
+	dif(Offset, 0),
+	succ(NewOffset, Offset),
+	day_print_map(DaysInMonth, NewOffset, R).
+
+day_print_map2(D, D, [D|R])	:- day_print_map(R).
+day_print_map2(D, N, [N|R]) :- dif(D,N), succ(N, N1), day_print_map2(D, N1, R).
+
+day_print_map([]).
+day_print_map(['   '|R]) :- day_print_map(R).
+
+% Figure out the number of days in a month based on whether it is a leap year or not.
+month_days(2, Year, Days) :-
+	is_leap_year(Year) -> Days = 29
+	; Days = 28.
+month_days(Month, _, Days) :-
+	dif(Month, 2),
+	nth1(Month, [31, _, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31], Days).
+
+% Figure out the space offset based on the day the month starts on.
+day_offset(D, D) :- dif(D, 7).
+day_offset(7, 0).
+
+% Test for leap years
+is_leap_year(Year) :-
+	0 is Year mod 100 -> 0 is Year mod 400
+	; 0 is Year mod 4.

Task/Calendar/Python/calendar.py

@@ -0,0 +1,43 @@
+>>> import calendar
+>>> help(calendar.prcal)
+Help on method pryear in module calendar:
+
+pryear(self, theyear, w=0, l=0, c=6, m=3) method of calendar.TextCalendar instance
+    Print a years calendar.
+
+>>> calendar.prcal(1969)
+                                  1969
+
+      January                   February                   March
+Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
+       1  2  3  4  5                      1  2                      1  2
+ 6  7  8  9 10 11 12       3  4  5  6  7  8  9       3  4  5  6  7  8  9
+13 14 15 16 17 18 19      10 11 12 13 14 15 16      10 11 12 13 14 15 16
+20 21 22 23 24 25 26      17 18 19 20 21 22 23      17 18 19 20 21 22 23
+27 28 29 30 31            24 25 26 27 28            24 25 26 27 28 29 30
+                                                    31
+
+       April                      May                       June
+Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
+    1  2  3  4  5  6                1  2  3  4                         1
+ 7  8  9 10 11 12 13       5  6  7  8  9 10 11       2  3  4  5  6  7  8
+14 15 16 17 18 19 20      12 13 14 15 16 17 18       9 10 11 12 13 14 15
+21 22 23 24 25 26 27      19 20 21 22 23 24 25      16 17 18 19 20 21 22
+28 29 30                  26 27 28 29 30 31         23 24 25 26 27 28 29
+                                                    30
+
+        July                     August                  September
+Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
+    1  2  3  4  5  6                   1  2  3       1  2  3  4  5  6  7
+ 7  8  9 10 11 12 13       4  5  6  7  8  9 10       8  9 10 11 12 13 14
+14 15 16 17 18 19 20      11 12 13 14 15 16 17      15 16 17 18 19 20 21
+21 22 23 24 25 26 27      18 19 20 21 22 23 24      22 23 24 25 26 27 28
+28 29 30 31               25 26 27 28 29 30 31      29 30
+
+      October                   November                  December
+Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
+       1  2  3  4  5                      1  2       1  2  3  4  5  6  7
+ 6  7  8  9 10 11 12       3  4  5  6  7  8  9       8  9 10 11 12 13 14
+13 14 15 16 17 18 19      10 11 12 13 14 15 16      15 16 17 18 19 20 21
+20 21 22 23 24 25 26      17 18 19 20 21 22 23      22 23 24 25 26 27 28
+27 28 29 30 31            24 25 26 27 28 29 30      29 30 31

Task/Calendar/REBOL/calendar.rebol

@@ -0,0 +1,13 @@
+Rebol []
+do [if "" = y: ask "Year (ENTER for current):^/^/" [prin y: now/year]
+foreach m system/locale/months [
+  prin rejoin ["^/^/     " m "^/^/ "]
+  foreach day system/locale/days [prin join copy/part day 2 " "]
+  print ""  f: to-date rejoin ["1-"m"-"y]  loop f/weekday - 1 [prin "   "]
+  repeat i 31 [
+    if attempt [c: to-date rejoin [i"-"m"-"y]][
+      prin join either 1 = length? form i ["  "][" "] i
+      if c/weekday = 7 [print ""]
+    ]
+  ]
+] ask "^/^/Press [ENTER] to Continue..."]

Task/Calendar/REXX/calendar.rexx

@@ -0,0 +1,147 @@
+/*REXX program to show any year's (monthly) calendar (with/without grid)*/
+
+@abc='abcdefghijklmnopqrstuvwxyz'; @abcU=@abc; upper @abcU
+calfill=' '; mc=12; _='1 3 1234567890' "fb"x
+parse var _ grid calspaces # chk . cv_ days.1 days.2 days.3 daysn sd sw
+_=0; parse var _ cols 1 jd 1 lowerCase 1 maxKalPuts 1 narrow 1,
+                 narrower 1 narrowest 1 short 1 shorter 1 shortest 1,
+                 small 1 smaller 1 smallest 1 upperCase
+parse arg mm '/' dd "/" yyyy _ '(' ops;  uops=ops
+if _\=='' | \is#(mm) | \is#(dd) | \is#(yyyy) then call erx 86
+
+  do while ops\==''; ops=strip(ops,'L'); parse var ops _1 2 1 _ . 1 _o ops
+  upper _
+       select
+       when  abb('CALSPaces')  then calspaces=nai()
+       when  abb('DEPth')      then        sd=nai()
+       when abbn('GRIDs')      then      grid=no()
+       when abbn('LOWercase')  then lowerCase=no()
+       when  abb('CALMONths')  then        mc=nai()
+       when abbn('NARrow')     then    narrow=no()
+       when abbn('NARROWER')   then  narrower=no()
+       when abbn('NARROWESt')  then narrowest=no()
+       when abbn('SHORt')      then     short=no()
+       when abbn('SHORTER')    then   shorter=no()
+       when abbn('SHORTESt')   then  shortest=no()
+       when abbn('SMALl')      then     small=no()
+       when abbn('SMALLER')    then   smaller=no()
+       when abbn('SMALLESt')   then  smallest=no()
+       when abbn('UPPercase')  then upperCase=no()
+       when  abb('WIDth')      then        sw=nai()
+       otherwise nop
+       end    /*select*/
+  end         /*do while opts\== ...*/
+
+mc=int(mc,'monthscalender'); if mc>0 then cal=1
+days='Sunday Monday Tuesday Wednesday Thursday Friday Saturday'
+months='January February March April May June July August September October November December'
+days=' 'days;  months=' 'months
+cyyyy=right(date(),4);  hyy=left(cyyyy,2);  lyy=right(cyyyy,2)
+dy.=31; _=30; parse var _ dy.4 1 dy.6 1 dy.9 1 dy.11; dy.2=28+ly(yyyy)
+yy=right(yyyy,2); sd=p(sd 43); sw=p(sw 80); cw=10; cindent=1; calwidth=76
+if small    then do; narrow=1   ; short=1   ; end
+if smaller  then do; narrower=1 ; shorter=1 ; end
+if smallest then do; narrowest=1; shortest=1; end
+if shortest then shorter=1
+if shorter  then short  =1
+if narrow    then do; cw=9; cindent=3; calwidth=69; end
+if narrower  then do; cw=4; cindent=1; calwidth=34; end
+if narrowest then do; cw=2; cindent=1; calwidth=20; end
+cv_=calwidth+calspaces+2
+calfill=left(copies(calfill,cw),cw)
+      do j=1 for 7;         _=word(days,j)
+            do jw=1 for 3;  _d=strip(substr(_,cw*jw-cw+1,cw))
+            if jw=1 then _d=centre(_d,cw+1)
+                    else _d=left(_d,cw+1)
+            days.jw=days.jw||_d
+            end   /*jw*/
+      __=daysn
+      if narrower  then daysn=__||centre(left(_,3),5)
+      if narrowest then daysn=__||center(left(_,2),3)
+      end   /*j*/
+_yyyy=yyyy; calPuts=0; cv=1; _mm=mm+0; month=word(months,mm)
+dy.2=28+ly(_yyyy); dim=dy._mm; _dd=01; dow=dow(_mm,_dd,_yyyy); $dd=dd+0
+
+/*─────────────────────────────now: the business of the building the cal*/
+call calGen
+               do _j=2 to mc
+               if cv_\=='' then do
+                                cv=cv+cv_
+                                if cv+cv_>=sw then do; cv=1; call calPut
+                                                   call fcalPuts;call calPb
+                                                   end
+                                              else calPuts=0
+                                end
+                           else do;call calPb;call calPut;call fcalPuts;end
+               _mm=_mm+1;  if _mm==13 then do;  _mm=1; _yyyy=_yyyy+1;  end
+               month=word(months,_mm); dy.2=28+ly(_yyyy); dim=dy._mm
+               dow=dow(_mm,_dd,_yyyy); $dd=0; call calGen
+               end   /*_j*/
+call fcalPuts
+return _
+
+/*─────────────────────────────calGen subroutine────────────────────────*/
+calGen: cellX=;cellJ=;cellM=;calCells=0;calline=0
+call calPut
+call calPutl copies('─',calwidth),"┌┐"; call calHd
+call calPutl month ' ' _yyyy          ; call calHd
+if narrowest | narrower then call calPutl daysn
+                        else do jw=1 for 3
+                             if space(days.jw)\=='' then call calPutl days.jw
+                             end
+calft=1; calfb=0
+  do jf=1 for dow-1; call cellDraw calFill,calFill; end
+  do jy=1 for dim; call cellDraw jy; end
+calfb=1
+  do 7; call cellDraw calFill,calFill; end
+if sd>32 & \shorter then call calPut
+return
+
+/*─────────────────────────────cellDraw subroutine──────────────────────*/
+cellDraw: parse arg zz,cdDOY;zz=right(zz,2);calCells=calCells+1
+if calCells>7 then do
+                   calLine=calLine+1
+                   cellX=substr(cellX,2)
+                   cellJ=substr(cellJ,2)
+                   cellM=substr(cellM,2)
+                   cellB=translate(cellX,,")(─-"#)
+                   if calLine==1 then call cx
+                   call calCsm; call calPutl cellX; call calCsj; call cx
+                   cellX=; cellJ=; cellM=; calCells=1
+                   end
+cdDOY=right(cdDOY,cw); cellM=cellM'│'center('',cw)
+cellX=cellX'│'centre(zz,cw); cellJ=cellJ'│'center('',cw)
+return
+
+/*═════════════════════════════general 1-line subs══════════════════════*/
+abb:arg abbu;parse arg abb;return abbrev(abbu,_,abbl(abb))
+abbl:return verify(arg(1)'a',@abc,'M')-1
+abbn:parse arg abbn;return abb(abbn)|abb('NO'abbn)
+calCsj:if sd>49&\shorter then call calPutl cellB;if sd>24&\short then call calPutl cellJ; return
+calCsm:if sd>24&\short then call calPutl cellM;if sd>49&\shorter then call calPutl cellB;return
+calHd:if sd>24&\shorter then call calPutl;if sd>32&\shortest then call calPutl;return
+calPb:if \grid&shortest then call put chk;return
+calPut:calPuts=calPuts+1;maxKalPuts=max(maxKalPuts,calPuts);if symbol('CT.'calPuts)\=='VAR' then ct.calPuts=;ct.calPuts=overlay(arg(1),ct.calPuts,cv);return
+calPutl:call calPut copies(' ',cindent)left(arg(2)"│",1)center(arg(1),calwidth)||right('│'arg(2),1);return
+cx:cx_='├┤';cx=copies(copies('─',cw)'┼',7);if calft then do;cx=translate(cx,'┬',"┼");calft=0;end;if calfb then do;cx=translate(cx,'┴',"┼");cx_='└┘';calfb=0;end;call calPutl cx,cx_;return
+dow:procedure;arg m,d,y;if m<3 then do;m=m+12;y=y-1;end;yl=left(y,2);yr=right(y,2);w=(d+(m+1)*26%10+yr+yr%4+yl%4+5*yl)//7;if w==0 then w=7;return w
+er:parse arg _1,_2;call '$ERR' "14"p(_1) p(word(_1,2) !fid(1)) _2;if _1<0 then return _1;exit result
+err:call er '-'arg(1),arg(2);return ''
+erx:call er '-'arg(1),arg(2);exit ''
+fcalPuts: do j=1 for maxKalPuts;call put ct.j;end;ct.=;maxKalPuts=0;calPuts=0;return
+int:int=numx(arg(1),arg(2));if \isint(int) then call erx 92,arg(1) arg(2);return int/1
+is#:return verify(arg(1),#)==0
+isint:return datatype(arg(1),'W')
+lower:return translate(arg(1),@abc,@abcU)
+ly:arg _;if length(_)==2 then _=hyy||_;ly=_//4==0;if ly==0 then return 0;ly=((_//100\==0)|_//400==0);return ly
+na:if arg(1)\=='' then call erx 01,arg(2);parse var ops na ops;if na=='' then call erx 35,_o;return na
+nai:return int(na(),_o)
+nan:return numx(na(),_o)
+no:if arg(1)\=='' then call erx 01,arg(2);return left(_,2)\=='NO'
+num:procedure;parse arg x .,f,q;if x=='' then return x;if datatype(x,'N') then return x/1;x=space(translate(x,,','),0);if datatype(x,'N') then return x/1;return numnot()
+numnot:if q==1 then return x;if q=='' then call er 53,x f;call erx 53,x f
+numx:return num(arg(1),arg(2),1)
+p:return word(arg(1),1)
+put:_=arg(1);_=translate(_,,'_'chk);if \grid then _=ungrid(_);if lowerCase then _=lower(_);if upperCase then upper _;if shortest&_=' ' then return;call tell _;return
+tell:say arg(1);return
+ungrid:return translate(arg(1),,"│║─═┤┐└┴┬├┼┘┌╔╗╚╝╟╢╞╡╫╪╤╧╥╨╠╣")

Task/Calendar/Racket/calendar.rkt

@@ -0,0 +1,32 @@
+#lang racket
+(require racket/date net/base64 file/gunzip)
+(define (calendar yr)
+  (define (nsplit n l) (if (null? l) l (cons (take l n) (nsplit n (drop l n)))))
+  (define months
+    (for/list ([mn (in-naturals 1)]
+               [mname '(January February March April May June July
+                        August September October November December)])
+      (define s (find-seconds 0 0 12 1 mn yr))
+      (define pfx (date-week-day (seconds->date s)))
+      (define days
+        (let ([? (if (= mn 12) (λ(x y) y) (λ(x y) x))])
+          (round (/ (- (find-seconds 0 0 12 1 (? (+ 1 mn) 1) (? yr (+ 1 yr))) s)
+                    60 60 24))))
+      (list* (~a mname #:width 20 #:align 'center) "Su Mo Tu We Th Fr Sa"
+             (map string-join
+                  (nsplit 7 `(,@(make-list pfx "  ")
+                              ,@(for/list ([d days])
+                                  (~a (+ d 1) #:width 2 #:align 'right))
+                              ,@(make-list (- 42 pfx days) "  ")))))))
+  (let ([s #"nZA7CsAgDED3nCLgoAU/3Uvv4SCE3qKD5OyNWvoBhdIHSswjMYp4YR2z80Tk8StOgP
+             sY0EyrMZOE6WsL3u4G5lyV+d8MyVOy8hZBt7RSMca9Ac/KUIs1L/BOysb50XMtMzEj
+             ZqiuRxIVqI+4kSpy7GqpXNsz+bfpfWIGOAA="]
+        [o (open-output-string)])
+    (inflate (open-input-bytes (base64-decode s)) o)
+    (display (regexp-replace #rx"~a" (get-output-string o) (~a yr))))
+  (for-each displayln
+    (dropf-right (for*/list ([3ms (nsplit 3 months)] [s (apply map list 3ms)])
+                   (regexp-replace #rx" +$" (string-join s "   ") ""))
+                 (λ(s) (equal? "" s)))))
+
+(calendar 1969)

Task/Calendar/Raku/calendar.raku

@@ -0,0 +1,29 @@
+my $months-per-row = 3;
+my @weekday-names  = <Mo Tu We Th Fr Sa Su>;
+my @month-names    = <Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec>;
+
+my Int() $year = @*ARGS.shift || 1969;
+say fmt-year($year);
+
+sub fmt-year ($year) {
+    my @month-strs;
+    @month-strs[$_] = [fmt-month($year, $_).lines] for 1 .. 12;
+    my @C = ' ' x 30 ~ $year, '';
+    for 1, 1+$months-per-row ... 12 -> $month {
+        while @month-strs[$month] {
+            for ^$months-per-row -> $column {
+                @C[*-1] ~= @month-strs[$month+$column].shift ~ ' ' x 3 if @month-strs[$month+$column];
+            }
+            @C.push: '';
+        }
+        @C.push: '';
+    }
+    @C.join: "\n";
+}
+
+sub fmt-month ($year, $month) {
+    my $date = Date.new($year,$month,1);
+    @month-names[$month-1].fmt("%-20s\n") ~ @weekday-names ~ "\n" ~
+    (('  ' xx $date.day-of-week - 1), (1..$date.days-in-month)».fmt('%2d')).flat.rotor(7, :partial).join("\n") ~
+    (' ' if $_ < 7) ~ ('  ' xx 7-$_).join(' ') given Date.new($year, $month, $date.days-in-month).day-of-week;
+}

Task/Calendar/Ring/calendar.ring

@@ -0,0 +1,156 @@
+# Project : Calendar
+
+load "guilib.ring"
+load "stdlib.ring"
+
+new qapp
+       {
+        win1 = new qwidget() {
+
+                   day = list(12)
+                   pos = newlist(12,37)
+                   month = list(12)
+                   week = list(7)
+                   weekday = list(7)
+                   button = newlist(7,6)
+                   monthsnames = list(12)
+                   week = ["Su", "Mo", "Tu", "We", "Th", "Fr", "Sa"]
+                   months = ["January", "February", "March", "April", "May", "June", "July",
+                                   "August", "September", "October", "November", "December"]
+                   daysnew = [[5,1], [6,2], [7,3], [1,4], [2,5], [3,6], [4,7]]
+                   mo = [4,0,0,3,5,1,3,6,2,4,0,2]
+                   mon = [31,28,31,30,31,30,31,31,30,31,30,31]
+                   m2 = (((1969-1900)%7) + floor((1969 - 1900)/4) % 7) % 7
+                   for n = 1 to 12
+                        month[n] = (mo[n] + m2) % 7
+                        x = (month[n] + 1) % 7 + 1
+                       for m = 1 to len(daysnew)
+                            if daysnew[m][1] = x
+                              nr = m
+                           ok
+                       next
+                       day[n] = daysnew[nr][2]
+                  next
+                  for m = 1 to 12
+                       for n = 1 to day[m] - 1
+                            pos[m][n] = "  "
+                       next
+                  next
+                  for m = 1 to 12
+                       for  n = day[m] to 37
+                             if n < (mon[m] + day[m])
+                                pos[m][n] = n - day[m] + 1
+                             else
+                                pos[m][n] = "  "
+                             ok
+                       next
+                  next
+                  setwindowtitle("Calendar")
+                  setgeometry(100,100,650,800)
+                  label1 = new qlabel(win1) {
+                              setgeometry(10,10,800,600)
+                              settext("")
+                  }
+                 year = new qpushbutton(win1)
+                                                  {
+                                                  setgeometry(280,20,60,20)
+                                                  year.settext("1969")
+                                                  }
+                 for n = 1 to 4
+                      nr = (n-1)*3+1
+                     showmonths(nr)
+                 next
+                 for n = 1 to 12
+                     showweeks(n)
+                 next
+                 for n = 1 to 12
+                     showdays(n)
+                 next
+                 show()
+        }
+        exec()
+        }
+
+func showmonths(m)
+       for n = m to m + 2
+            monthsnames[n] = new qpushbutton(win1)
+                                        {
+                                        if n%3 = 1
+                                           col = 120
+                                           rownr = floor(n/3)
+                                           if rownr = 0
+                                              rownr = n/3
+                                           ok
+                                           if n = 1
+                                              row = 40
+                                           else
+                                              row = 40+rownr*180
+                                           ok
+                                        else
+                                           colnr = n%3
+                                           if colnr = 0
+                                              colnr = 3
+                                           ok
+                                           rownr = floor(n/3)
+                                           if n%3 = 0
+                                              rownr = floor(n/3)-1
+                                           ok
+                                           col = 120 + (colnr-1)*160
+                                           row = 40 + rownr*180
+                                        ok
+                                        setgeometry(col,row,60,20)
+                                        monthsnames[n].settext(months[n])
+                                        }
+       next
+
+func showweeks(n)
+        for m = 1 to 7
+             col = m%7
+             if col = 0 col = 7 ok
+             weekday[m] = new qpushbutton(win1)
+                                  {
+                                  colnr = n % 3
+                                  if colnr = 0
+                                     colnr = 3
+                                  ok
+                                  rownr = floor(n/3)
+                                  if n%3 = 0
+                                     rownr = floor(n/3)-1
+                                  ok
+                                  colbegin = 60 + (colnr-1)*160
+                                  rowbegin = 60 + (rownr)*180
+                                  setgeometry(colbegin+col*20,rowbegin,20,20)
+                                  weekday[m].settext(week[m])
+                                  }
+        next
+
+func showdays(ind)
+        rownr = floor(ind/3)
+        if ind%3 = 0
+           rownr = floor(ind/3)-1
+        ok
+        rowbegin = 60+rownr*180
+        for m = 1 to 6
+             for n = 1 to 7
+                  col = n%7
+                  if col = 0 col = 7 ok
+                  row = m
+                   button[n][m] = new qpushbutton(win1)
+                                         {
+                                          if ind%3 = 1
+                                             colbegin = 60
+                                          elseif ind%3 = 2
+                                             colbegin = 220
+                                          else
+                                             colbegin = 380
+                                          ok
+                                          setgeometry(colbegin+col*20,rowbegin+row*20,20,20)
+                                          nr = (m-1)*7+n
+                                          if nr <= 37
+                                             if pos[ind][nr] != "  "
+                                                button[n][m].settext(string(pos[ind][nr]))
+                                             ok
+                                          ok
+                                          }
+             next
+        next

Task/Calendar/Ruby/calendar.rb

@@ -0,0 +1,70 @@
+require 'date'
+
+# Creates a calendar of _year_. Returns this calendar as a multi-line
+# string fit to _columns_.
+def cal(year, columns)
+
+  # Start at January 1.
+  #
+  # Date::ENGLAND marks the switch from Julian calendar to Gregorian
+  # calendar at 1752 September 14. This removes September 3 to 13 from
+  # year 1752. (By fortune, it keeps January 1.)
+  #
+  date = Date.new(year, 1, 1, Date::ENGLAND)
+
+  # Collect calendars of all 12 months.
+  months = (1..12).collect do |month|
+    rows = [Date::MONTHNAMES[month].center(20), "Su Mo Tu We Th Fr Sa"]
+
+    # Make array of 42 days, starting with Sunday.
+    days = []
+    date.wday.times { days.push "  " }
+    while date.month == month
+      days.push("%2d" % date.mday)
+      date += 1
+    end
+    (42 - days.length).times { days.push "  " }
+
+    days.each_slice(7) { |week| rows.push(week.join " ") }
+    next rows
+  end
+
+  # Calculate months per row (mpr).
+  #  1. Divide columns by 22 columns per month, rounded down. (Pretend
+  #     to have 2 extra columns; last month uses only 20 columns.)
+  #  2. Decrease mpr if 12 months would fit in the same months per
+  #     column (mpc). For example, if we can fit 5 mpr and 3 mpc, then
+  #     we use 4 mpr and 3 mpc.
+  mpr = (columns + 2).div 22
+  mpr = 12.div((12 + mpr - 1).div mpr)
+
+  # Use 20 columns per month + 2 spaces between months.
+  width = mpr * 22 - 2
+
+  # Join months into calendar.
+  rows = ["[Snoopy]".center(width), "#{year}".center(width)]
+  months.each_slice(mpr) do |slice|
+    slice[0].each_index do |i|
+      rows.push(slice.map {|a| a[i]}.join "  ")
+    end
+  end
+  return rows.join("\n")
+end
+
+
+ARGV.length == 1 or abort "usage: #{$0} year"
+
+# Guess width of terminal.
+#  1. Obey environment variable COLUMNS.
+#  2. Try to require 'io/console' from Ruby 1.9.3.
+#  3. Try to run `tput co`.
+#  4. Assume 80 columns.
+columns = begin Integer(ENV["COLUMNS"] || "")
+          rescue
+            begin require 'io/console'; IO.console.winsize[1]
+            rescue LoadError
+              begin Integer(`tput cols`)
+              rescue
+                80; end; end; end
+
+puts cal(Integer(ARGV[0]), columns)

Task/Calendar/Rust/calendar.rust

@@ -0,0 +1,98 @@
+// Assume your binary name is 'calendar'.
+// Command line:
+// >>$ calendar 2019 150
+// First argument: year number.
+// Second argument (optional): text area width (in characters).
+
+extern crate chrono;
+
+use std::{env, cmp};
+use chrono::{NaiveDate, Datelike};
+
+const MONTH_WIDTH: usize = 22;
+
+fn print_header(months: &[&str]) {
+    const DAYS_OF_WEEK: &str = "SU MO TU WE TH FR SA  ";
+    println!();
+    for m in months {
+        print!("{:^20}  ", m);
+    }
+    println!("\n{}", DAYS_OF_WEEK.repeat(months.len()));
+}
+
+fn get_week_str(days: i32, week_num: i32, start_day_of_week: i32) -> Option<String> {
+    let start = week_num * 7 - start_day_of_week + 1;
+    let end = (week_num + 1) * 7 - start_day_of_week;
+    let mut ret = String::with_capacity(MONTH_WIDTH);
+    if start > days {
+        None
+    } else {
+        for i in start..(end + 1) {
+            if i <= 0 || i > days {
+                ret.push_str("  ");
+            } else {
+                if i < 10 {
+                    ret.push_str(" ");
+                }
+                ret.push_str(&i.to_string());
+            }
+            ret.push_str(" ");
+        }
+        ret.push_str(" ");
+        Some(ret)
+    }
+}
+
+fn main() {
+    const MONTH_NAMES: [&str; 12] = ["JANUARY", "FEBRUARY", "MARCH", "APRIL", "MAY", "JUNE", "JULY",
+                                     "AUGUST", "SEPTEMBER", "OCTOBER", "NOVEMBER", "DECEMBER"];
+    const DEFAULT_TEXT_WIDTH: usize = 100;
+
+    let args: Vec<String> = env::args().collect();
+    let year: i32 = args[1].parse().expect("The first argument must be a year");
+    let width: usize = if args.len() > 2 {
+        cmp::max(MONTH_WIDTH, args[2].parse().expect("The second argument should be text width"))
+    } else {
+        DEFAULT_TEXT_WIDTH
+    };
+    let months_in_row = width / MONTH_WIDTH;
+    let month_rows = if MONTH_NAMES.len() % months_in_row == 0 {
+        MONTH_NAMES.len() / months_in_row
+    } else {
+        MONTH_NAMES.len() / months_in_row + 1
+    };
+
+    let start_days_of_week: Vec<i32> =
+        (1..13).map(|x| NaiveDate::from_ymd(year, x, 1).weekday().num_days_from_sunday() as i32).collect();
+
+    let month_days: [i32; 12] = if NaiveDate::from_ymd_opt(year, 2, 29).is_some() {
+        [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
+    } else {
+        [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
+    };
+
+    println!("{year:^w$}", w=width, year=year.to_string());
+    for i in 0..month_rows {
+        let start = i * months_in_row;
+        let end = cmp::min((i + 1) * months_in_row, MONTH_NAMES.len());
+        print_header(&MONTH_NAMES[start..end]);
+        let mut count = 0;
+        let mut row_num = 0;
+        while count < months_in_row {
+            let mut row_str = String::with_capacity(width);
+            for j in start..end {
+                match get_week_str(month_days[j], row_num, start_days_of_week[j]) {
+                    None => {
+                        count += 1;
+                        row_str.push_str(&" ".repeat(MONTH_WIDTH));
+                    },
+                    Some(week_str) => row_str.push_str(&week_str)
+                }
+            }
+            if count < months_in_row {
+                println!("{}", row_str);
+            }
+            row_num += 1;
+        }
+    }
+}

Task/Calendar/SPL/calendar.spl

@@ -0,0 +1,37 @@
+year = 1969
+#.output(#.str(year,">68<"))
+> row, 0..3
+  > col, 1..3
+    cal[col] = mcal(row*3+col,year)
+    size = #.size(cal[col],1)
+  <
+  > i, 1..8
+    str = ""
+    > col, 1..3
+      ? col>1, str += "    "
+      line = ""
+      ? #.size(cal[col],1)!<i, line = cal[col][i]
+      str += #.str(line,"<20<")
+    <
+    #.output(str)
+  <
+<
+mcal(m,y)=
+  months = ["January","February","March","April","May","June","July","August","September","October","November","December"]
+  days = [31,28,31,30,31,30,31,31,30,31,30,31]
+  ? y%4=0, days[2] = 29
+  lines = #.array(0)
+  lines[1] = #.str(months[m],">20<")
+  lines[2] = "Mo Tu We Th Fr Sa Su"
+  n = 3
+  > i, 1..#.weekday(1,m,y)-1
+    lines[n] += "   "
+  <
+  > d, 1..days[m]
+    wd = #.weekday(d,m,y)
+    lines[n] += #.str(d,">2>")
+    ? wd<7, lines[n] += " "
+    ? wd=7, n += 1
+  <
+  <= lines
+.

Task/Calendar/Scala/calendar-1.scala

@@ -0,0 +1,153 @@
+import java.util.{ Calendar, GregorianCalendar }
+import language.postfixOps
+import collection.mutable.ListBuffer
+
+object CalendarPrint extends App {
+  val locd = java.util.Locale.getDefault()
+  val cal = new GregorianCalendar
+  val monthsMax = cal.getMaximum(Calendar.MONTH)
+
+  def JDKweekDaysToISO(dn: Int) = {
+    val nday = dn - Calendar.MONDAY
+    if (nday < 0) (dn + Calendar.THURSDAY) else nday
+  }
+
+  def daysInMonth(year: Int, monthMinusOne: Int): Int = {
+    cal.set(year, monthMinusOne, 1)
+    cal.getActualMaximum(Calendar.DAY_OF_MONTH)
+  }
+
+  def namesOfMonths() = {
+    def f1(i: Int): String = {
+      cal.set(2013, i, 1)
+      cal.getDisplayName(Calendar.MONTH, Calendar.LONG, locd)
+    }
+    (0 to monthsMax) map f1
+  }
+
+  def offsets(year: Int): List[Int] = {
+    val months = cal.getMaximum(Calendar.MONTH)
+    def get1stDayOfWeek(i: Int) = {
+      cal.set(year, i, 1)
+      cal.get(Calendar.DAY_OF_WEEK)
+    }
+    (0 to monthsMax).toList map get1stDayOfWeek map { i => JDKweekDaysToISO(i) }
+  }
+
+  def headerNameOfDays() = {
+    val mdow = cal.getDisplayNames(Calendar.DAY_OF_WEEK, Calendar.SHORT, locd) // map days of week
+    val it = mdow.keySet.iterator
+    val keySet = new ListBuffer[String]
+    while (it.hasNext) keySet += it.next
+    (keySet.map { key => (JDKweekDaysToISO(mdow.get(key)), key.take(2))
+    }.sortWith(_._1 < _._1) map (_._2)).mkString(" ")
+  }
+
+  def getGregCal(year: Int) = {
+    {
+
+      def dayOfMonth(month: Int) = new Iterator[(Int, Int)] {
+        cal.set(year, month, 1)
+        var ldom = 0
+
+        def next() = {
+          val res = (cal.get(Calendar.MONTH), cal.get(Calendar.DAY_OF_MONTH))
+          ldom = res._2
+          cal.roll(Calendar.DAY_OF_MONTH, true)
+          res
+        }
+
+        def hasNext() = (cal.get(Calendar.DAY_OF_MONTH) > ldom)
+      }
+      var ret: List[(Int, Int)] = Nil
+      for (i <- 0 to monthsMax) ret = ret ++ (dayOfMonth(i).toSeq)
+      (ret, offsets(year))
+    }
+  }
+
+  def printCalendar(calendar: (List[(Int, Int)], List[Int]),
+                    headerList: List[String] = Nil,
+                    printerWidth: Int = 80) = {
+    val mw = 20 // month width
+    val gwf = 2 // gap width fixed
+    val gwm = 2 // gap width minimum
+    val fgw = true
+
+    val arr = Array.ofDim[String](6, 7)
+
+    def limits(printerWidth: Int): (Int, Int, Int, Int, Int) = {
+      val pw = if (printerWidth < 20) 20 else if (printerWidth > 300) 300 else printerWidth
+
+      // months side by side, gaps sum minimum
+      val (msbs, gsm) = {
+        val x1 = {
+          val c = if (pw / mw > 12) 12 else pw / mw
+          val a = (c - 1)
+          if (c * mw + a * gwm <= pw) c else a
+        } match {
+          case 5                      => 4
+          case a if (a > 6 && a < 12) => 6
+          case other                  => other
+        }
+        (x1, (x1 - 1) * gwm)
+      }
+
+      def getFGW(msbs: Int, gsm: Int) = { val r = (pw - msbs * mw - gsm) / 2; (r, gwf, r) } // fixed gap width
+      def getVGW(msbs: Int, gsm: Int) = pw - msbs * mw - gsm match { // variable gap width
+        case a if (a < 2 * gwm) => (a / 2, gwm, a / 2)
+        case b                  => { val x = (b + gsm) / (msbs + 1); (x, x, x) }
+      }
+
+      // left margin, gap width, right margin
+      val (lm, gw, rm) = if (fgw) getFGW(msbs, gsm) else getVGW(msbs, gsm)
+      (pw, msbs, lm, gw, rm)
+    } // def limits(
+
+    val (pw, msbs, lm, gw, rm) = limits(printerWidth)
+    val monthsList = (0 to monthsMax).map { m => calendar._1.filter { _._1 == m } }
+    val nom = namesOfMonths()
+    val hnod = headerNameOfDays
+
+    def fsplit(list: List[(Int, Int)]): List[String] = {
+      def fap(p: Int) = (p / 7, p % 7)
+      for (i <- 0 until 6) for (j <- 0 until 7) arr(i)(j) = "  "
+      for (i <- 0 until list.size)
+        arr(fap(i + calendar._2(list(i)._1))._1)(fap(i + calendar._2(list(i)._1))._2) =
+          f"${(list(i)._2)}%2d"
+      arr.toList.map(_.foldRight("")(_ + " " + _))
+    }
+    val monthsRows = monthsList.map(fsplit)
+
+    def center(s: String, l: Int): String = {
+      (if (s.size >= l) s
+      else " " * ((l - s.size) / 2) + s + " " * ((l - s.size) / 2) + " ").substring(0, l)
+    }
+
+    val maxMonths = monthsMax + 1
+
+    val rowblocks = (1 to maxMonths / msbs).map { i =>
+      (0 to 5).map { j =>
+        val lb = new ListBuffer[String]
+        val k = (i - 1) * msbs
+        (k to k + msbs - 1).map { l => lb += monthsRows(l)(j) }
+        lb
+      }
+    }
+
+    val mheaders = (1 to maxMonths / msbs).
+      map { i => (0 to msbs - 1).map { j => center(nom(j + (i - 1) * msbs), 20) } }
+    val dowheaders = (1 to maxMonths / msbs).
+      map { i => (0 to msbs - 1).map { j => center(hnod, 20) } }
+
+    headerList.foreach(xs => println(center(xs + '\n', pw)))
+    (1 to 12 / msbs).foreach { i =>
+      println(" " * lm + mheaders(i - 1).foldRight("")(_ + " " * gw + _))
+      println(" " * lm + dowheaders(i - 1).foldRight("")(_ + " " * gw + _))
+      rowblocks(i - 1).foreach { xs => println(" " * lm + xs.foldRight("")(_ + " " * (gw - 1) + _)) }
+      println
+    }
+  } //  def printCal(
+
+  printCalendar(getGregCal(1969), List("[Snoopy Picture]", "1969"))
+  printCalendar(getGregCal(1582), List("[Snoopy Picture]", "1582"), printerWidth = 132)
+}

Task/Calendar/Scala/calendar-2.scala

@@ -0,0 +1,50 @@
+/**
+ * Loosely based on the Ruby implementation.
+ *
+ * Focuses on immutability and Scala idioms,
+ * while trying to remain readable and clean.
+ */
+object YearCalendarApp extends App with Extras {
+
+  val defaultYear = 1752
+  val columns = 86
+
+  val year = args.headOption.map(_.toInt).getOrElse(defaultYear)
+
+  yearCalendarLines(year, columns).foreach(println)
+
+  def yearCalendarLines(year: Int, columns: Int): Seq[String] = {
+    // At least one. Divide rest columns by width + 2 spaces (separator)
+    val calendarsPerRow = 1 + (columns - 20) / (20 + 2)
+
+    // Use 20 columns per month + 2 spaces between months
+    val width = calendarsPerRow * 22 - 2
+
+    List(
+      "[Snoopy]".center(width),
+      s"${year}".center(width)) ++
+      // Get, group, transpose and join calendar lines
+      allMonthCalendarLines(year).grouped(calendarsPerRow).flatMap { calGroup =>
+        calGroup.transpose.map(stringsInRow => stringsInRow.mkString("  "))
+      }
+  }
+
+  def allMonthCalendarLines(year: Int): Seq[Seq[String]] = {
+    (1 to 12).map { monthNr =>
+      val date = MonthCalendar(monthInYear = monthNr, year)
+
+      // Make array of 42 days (7 * 6 weeks max.) starting with Sunday (which is 0)
+      val daySlotsInMonth = {
+        (Seq().padTo(date.dayOfWeek, "  ") ++
+          date.daysInMonth.map { dayNr => "%2d".format(dayNr) }).
+          padTo(42, "  ")
+      }
+
+      List(
+        date.monthName.center(20),
+        "Su Mo Tu We Th Fr Sa") ++
+        daySlotsInMonth.grouped(7).map { weekSlots => weekSlots.mkString(" ") }
+    }
+  }
+
+}

Task/Calendar/Scala/calendar-3.scala

@@ -0,0 +1,53 @@
+/**
+ * This provides extra classes needed for the main
+ * algorithm.
+ */
+trait Extras {
+
+  import java.util.Calendar
+  import java.util.GregorianCalendar
+  import java.text.SimpleDateFormat
+  import java.util.Locale
+
+  import scala.collection.mutable.Buffer
+
+  implicit class MyString(str: String) {
+    def center(width: Int): String = {
+      val leftSpaces = (width / 2) - (str.length() / 2)
+      val rightSpaces = width - (leftSpaces + str.length)
+      (" " * leftSpaces) + str + (" " * rightSpaces)
+    }
+  }
+
+  case class MonthCalendar(monthInYear: Int, year: Int) {
+    private val javaCalendar = makeJavaCalendar(year, monthInYear)
+    private def makeJavaCalendar(year: Int, monthInYear: Int): Calendar = {
+      val calendar = new GregorianCalendar()
+      // Actually, other countries changed already in 1582,
+      // which is the JDK's default implementation.
+      val gregorianDateChangeInEngland = {
+        val d = Calendar.getInstance()
+        d.set(1752, Calendar.SEPTEMBER, 14)
+        d.getTime()
+      }
+      // For England we need to set this explicitly.
+      calendar.setGregorianChange(gregorianDateChangeInEngland)
+      calendar.set(Calendar.DAY_OF_MONTH, 1)
+      calendar.set(Calendar.YEAR, year)
+      calendar.set(Calendar.MONTH, monthInYear - 1)
+      calendar
+    }
+    val monthName = javaCalendar.getDisplayName(Calendar.MONTH, Calendar.LONG, Locale.ENGLISH)
+    val dayOfWeek = javaCalendar.get(Calendar.DAY_OF_WEEK) - 1
+    val daysInMonth = {
+      val tempCal = makeJavaCalendar(year, monthInYear)
+      val dayNumbers = Buffer[Int]()
+      while (tempCal.get(Calendar.MONTH) == monthInYear - 1) {
+        dayNumbers += tempCal.get(Calendar.DAY_OF_MONTH)
+        tempCal.add(Calendar.DATE, 1)
+      }
+      dayNumbers
+    }
+  }
+
+}

Task/Calendar/Seed7/calendar.seed7

@@ -0,0 +1,53 @@
+$ include "seed7_05.s7i";
+  include "time.s7i";
+
+const func string: center (in string: stri, in integer: length) is
+  return ("" lpad (length - length(stri)) div 2 <& stri) rpad length;
+
+const proc: printCalendar (in integer: year, in integer: cols) is func
+  local
+    var time: date is time.value;
+    var integer: dayOfWeek is 0;
+    const array string: monthNames is [] ("January", "February", "March", "April", "May", "June",
+        "July", "August", "September", "October", "November", "December");
+    var array array string: monthTable is 12 times 9 times "";
+    var string: str is "";
+    var integer: month is 0;
+    var integer: position is 0;
+    var integer: row is 0;
+    var integer: column is 0;
+    var integer: line is 0;
+  begin
+    for month range 1 to 12 do
+      monthTable[month][1] := " " & center(monthNames[month], 20);
+      monthTable[month][2] := " Mo Tu We Th Fr Sa Su";
+      date := date(year, month, 1);
+      dayOfWeek := dayOfWeek(date);
+      for position range 1 to 43 do
+        if position >= dayOfWeek and position - dayOfWeek < daysInMonth(date.year, date.month) then
+          str := succ(position - dayOfWeek) lpad 3;
+        else
+          str := "" lpad 3;
+        end if;
+        monthTable[month][3 + pred(position) div 7] &:= str;
+      end for;
+    end for;
+    writeln(center("[Snoopy Picture]", cols * 24 + 4));
+    writeln(center(str(year),cols * 24 + 4));
+    writeln;
+    for row range 1 to succ(11 div cols) do
+      for line range 1 to 9 do
+        for column range 1 to cols do
+          if pred(row) * cols + column <= 12 then
+            write("   " & monthTable[pred(row) * cols + column][line]);
+          end if;
+        end for;
+        writeln;
+      end for;
+    end for;
+  end func;
+
+const proc: main is func
+  begin
+    printCalendar(1969, 3);
+  end func;

Task/Calendar/Sidef/calendar.sidef

@@ -0,0 +1,51 @@
+require('DateTime')
+
+define months_per_col = 3
+define week_day_names = <Mo Tu We Th Fr Sa Su>
+define month_names = <Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec>
+
+func fmt_month (year, month) {
+    var str = sprintf("%-20s\n", month_names[month-1])
+    str += week_day_names.join(' ')+"\n"
+
+    var dt = %s<DateTime>
+    var date = dt.new(year => year, month => month)
+    var week_day = date.day_of_week
+    str += (week_day-1 `of` "  " -> join(" "))
+
+    var last_day = dt.last_day_of_month(year => year, month => month).day
+    for day (date.day .. last_day) {
+        date = dt.new(year => year, month => month, day => day)
+        str += " " if (week_day ~~ (2..7))
+        if (week_day == 8) {
+            str += "\n"
+            week_day = 1
+        }
+        str += sprintf("%2d", day)
+        ++week_day
+    }
+    str += " " if (week_day < 8)
+    str += (8-week_day `of` "  " -> join(" "))
+    str += "\n"
+}
+
+func fmt_year (year) {
+    var month_strs = 12.of {|i| fmt_month(year, i+1).lines }
+
+    var str = (' '*30 + year + "\n")
+    for month (0..11 `by` months_per_col) {
+        while (month_strs[month]) {
+            for i (1..months_per_col) {
+                month_strs[month + i - 1] || next
+                str += month_strs[month + i - 1].shift
+                str += ' '*3
+            }
+            str += "\n"
+        }
+        str += "\n"
+    }
+
+    return str
+}
+
+print fmt_year(ARGV ? Number(ARGV[0]) : 1969)

Task/Calendar/Simula/calendar.simula

@@ -0,0 +1,144 @@
+BEGIN
+    INTEGER WIDTH, YEAR;
+    INTEGER COLS, LEAD, GAP;
+    TEXT ARRAY WDAYS(0:6);
+    CLASS MONTH(MNAME); TEXT MNAME;
+    BEGIN INTEGER DAYS, START_WDAY, AT_POS;
+    END MONTH;
+    REF(MONTH) ARRAY MONTHS(0:11);
+    WIDTH := 80; YEAR := 1969;
+
+    BEGIN
+        TEXT T;
+        INTEGER I, M;
+        FOR T :- "Su", "Mo", "Tu", "We", "Th", "Fr", "Sa" DO BEGIN
+            WDAYS(I) :- T; I := I+1;
+        END;
+        I := 0;
+        FOR T :- "January", "February", "March",
+                 "April", "May", "June",
+                 "July", "August", "September",
+                 "October", "November", "December" DO BEGIN
+            MONTHS(I) :- NEW MONTH(T); I := I+1;
+        END;
+        I := 0;
+        FOR M := 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 DO BEGIN
+            MONTHS(I).DAYS := M; I := I+1;
+        END;
+    END;
+
+    BEGIN
+
+        PROCEDURE SPACE(N); INTEGER N;
+        BEGIN
+            WHILE N > 0 DO BEGIN
+                OUTCHAR(' '); N := N-1;
+            END;
+        END SPACE;
+
+        PROCEDURE INIT_MONTHS;
+        BEGIN
+            INTEGER I;
+
+            IF MOD(YEAR,4) = 0 AND MOD(YEAR,100) <> 0 OR MOD(YEAR,400) = 0 THEN
+                MONTHS(1).DAYS := 29;
+
+            YEAR := YEAR-1;
+            MONTHS(0).START_WDAY
+                := MOD(YEAR * 365 + YEAR//4 - YEAR//100 + YEAR//400 + 1, 7);
+
+            FOR I := 1 STEP 1 UNTIL 12-1 DO
+                MONTHS(I).START_WDAY :=
+                    MOD(MONTHS(I-1).START_WDAY + MONTHS(I-1).DAYS, 7);
+
+            COLS := (WIDTH + 2) // 22;
+            WHILE MOD(12,COLS) <> 0 DO
+                COLS := COLS-1;
+            GAP := IF COLS - 1 <> 0 THEN (WIDTH - 20 * COLS) // (COLS - 1) ELSE 0;
+            IF GAP > 4 THEN
+                GAP := 4;
+            LEAD := (WIDTH - (20 + GAP) * COLS + GAP + 1) // 2;
+            YEAR := YEAR+1;
+        END INIT_MONTHS;
+
+        PROCEDURE PRINT_ROW(ROW); INTEGER ROW;
+        BEGIN
+            INTEGER C, I, FROM, UP_TO;
+            INTEGER PROCEDURE PREINCREMENT(I); NAME I; INTEGER I;
+            BEGIN I := I+1; PREINCREMENT := I;
+            END PREINCREMENT;
+            INTEGER PROCEDURE POSTINCREMENT(I); NAME I; INTEGER I;
+            BEGIN POSTINCREMENT := I; I := I+1;
+            END POSTINCREMENT;
+            FROM := ROW * COLS;
+            UP_TO := FROM + COLS;
+            SPACE(LEAD);
+            FOR C := FROM STEP 1 UNTIL UP_TO-1 DO BEGIN
+                I := MONTHS(C).MNAME.LENGTH;
+                SPACE((20 - I)//2);
+                OUTTEXT(MONTHS(C).MNAME);
+                SPACE(20 - I - (20 - I)//2 + (IF C = UP_TO - 1 THEN 0 ELSE GAP));
+            END;
+            OUTIMAGE;
+
+            SPACE(LEAD);
+            FOR C := FROM STEP 1 UNTIL UP_TO-1 DO BEGIN
+                FOR I := 0 STEP 1 UNTIL 7-1 DO BEGIN
+                    OUTTEXT(WDAYS(I)); OUTTEXT(IF I = 6 THEN "" ELSE " ");
+                END;
+                IF C < UP_TO - 1 THEN
+                    SPACE(GAP)
+                ELSE
+                    OUTIMAGE;
+            END;
+
+            WHILE TRUE DO BEGIN
+                FOR C := FROM STEP 1 UNTIL UP_TO-1 DO
+                    IF MONTHS(C).AT_POS < MONTHS(C).DAYS THEN
+                        GO TO IBREAK;
+            IBREAK:
+                IF C = UP_TO THEN
+                    GO TO OBREAK;
+
+                SPACE(LEAD);
+                FOR C := FROM STEP 1 UNTIL UP_TO-1 DO BEGIN
+                    FOR I := 0 STEP 1 UNTIL MONTHS(C).START_WDAY-1 DO
+                        SPACE(3);
+                    WHILE POSTINCREMENT(I) < 7 AND MONTHS(C).AT_POS < MONTHS(C).DAYS DO BEGIN
+                        OUTINT(PREINCREMENT(MONTHS(C).AT_POS),2);
+                        IF I < 7 OR C < UP_TO - 1 THEN
+                            SPACE(1);
+                    END;
+                    WHILE POSTINCREMENT(I) <= 7 AND C < UP_TO-1 DO
+                        SPACE(3);
+                    IF C < UP_TO - 1 THEN
+                        SPACE(GAP - 1);
+                    MONTHS(C).START_WDAY := 0;
+                END;
+                OUTIMAGE;
+            END;
+        OBREAK:
+            OUTIMAGE;
+        END PRINT_ROW;
+
+        PROCEDURE PRINT_YEAR;
+        BEGIN
+            INTEGER ROW;
+            TEXT BUF;
+            INTEGER STRLEN;
+            BUF :- BLANKS(32); BUF.PUTINT(YEAR); BUF.SETPOS(1);
+            WHILE BUF.MORE AND THEN BUF.GETCHAR = ' ' DO
+                STRLEN := STRLEN+1;
+            BUF :- BUF.SUB(STRLEN+1, 32-STRLEN);
+            SPACE((WIDTH - BUF.LENGTH) // 2);
+            OUTTEXT(BUF); OUTIMAGE; OUTIMAGE;
+            WHILE ROW * COLS < 12 DO BEGIN
+                PRINT_ROW(ROW);
+                ROW := ROW+1;
+            END;
+        END PRINT_YEAR;
+
+        INIT_MONTHS;
+        PRINT_YEAR;
+    END;
+END;

Task/Calendar/Smalltalk/calendar-1.st

@@ -0,0 +1 @@
+CalendarPrinter printOnTranscriptForYearNumber: 1969

Task/Calendar/Smalltalk/calendar-2.st

@@ -0,0 +1,136 @@
+"Instance Variables:
+- yearToPrint: The year to print the calendar of
+- stream: The stream used to print the calendar
+- monthsOfYear: A collection of all the months of yearToPrint, for example January 1969, February 1969, and so on
+- currentMonths: Group of 3 months under print, for example from January to March or April to June, and so on
+- monthOfYearCurrentDate: A collection that associates a month with the date to print for that month. It is used to
+  know which day number should be printed for each month when iterating over the day of weeks of each row"
+Object subclass: #CalendarPrinter
+	instanceVariableNames: 'yearToPrint stream monthsOfYear currentMonths monthOfYearCurrentDate'
+	classVariableNames: ''
+	poolDictionaries: ''
+	category: 'CalendarPrinter'
+
+CalendarPrinter class>>printOnTranscriptForYearNumber: aYearNumber
+	(self for: (GregorianYear number: aYearNumber) on: Transcript) value
+
+CalendarPrinter class>>for: aYear on: aStream
+  	^self new initializeFor: aYear on: aStream
+
+initializeFor: aYear on: aStream
+	yearToPrint := aYear.
+	stream := aStream.	
+	monthsOfYear := yearToPrint months.
+	monthOfYearCurrentDate := monthsOfYear collect: [ :aMonthOfYear | aMonthOfYear firstDate ].
+
+value
+	"Prints the year number (header) and then its months"
+	self
+		printHeader;
+		printMonths.
+
+printHeader
+	"Prints the year number centered"
+	self center: yearToPrint number printString in: self numberOfCharactersPerLine.
+	stream newLine; newLine.
+
+printMonths
+	"Prints each group of 3 months, for example from January to March, then April to June and so on"
+	(January to: December by: 3*month) do: [ :aMonth | self printMonthsStartingOn: aMonth ].
+
+printMonthsStartingOn: aMonth
+	"For each group of 3 months starting in aMonth, prints the name of the month (header),
+	the name of the days of the week (Mo Tu ...), and then the day numbers"
+	currentMonths := aMonth to: aMonth next next.
+	self
+		printMonthsHeader;
+		printDaysOfWeekHeader;
+		printDayNumbers.	
+
+printMonthsHeader
+	"Prints the current group of 3 months names, centered"
+	currentMonths
+		do: [ :currentMonth | self center: currentMonth printString in: self numberOfCharactersPerMonth ]
+		separatedBy: [ stream space: 3 ].
+	stream newLine.
+
+printDaysOfWeekHeader
+	"Prints the names of the days of week for each month of the current group of 3 months"
+	currentMonths
+		do: [ :currentMonth | self printOneMonthDaysOfWeekHeader ]
+		separatedBy: [ stream space: 3 ].
+	stream newLine.
+
+printOneMonthDaysOfWeekHeader
+	"Prints the name of the days of week"
+	(Sunday to: Saturday)
+		do: [ :aDayOfWeek | stream nextPutAll: (aDayOfWeek printString first: 2) ]
+		separatedBy: [ stream space ]
+
+printDayNumbers
+	"While there are day numbers to print, prints them in a row"
+	[self hasDayNumbersToPrint] whileTrue: [ self printDayNumbersRow ].
+
+hasDayNumbersToPrint
+	"If any of the group of 3 months currently printing has day numbers to print returns true, otherwise false"
+	^currentMonths anySatisfy: [ :currentMonth | self isCurrentDateAtSameMonthOfYearAs: currentMonth ]
+
+isCurrentDateAtSameMonthOfYearAs: currentMonth
+	"Returns true if the date to print for currentMonth is actually for the currentMonth"
+	^(self currentDateOf: currentMonth) month = currentMonth
+
+printDayNumbersRow
+	"For each month of the group of 3, prints a row of day numbers"
+	currentMonths
+		do: [ :currentMonth | self printDayNumbersRowOf: currentMonth ]
+		separatedBy: [ stream space: 3 ].
+	stream newLine
+
+printDayNumbersRowOf: currentMonth
+	"Prints the day numbers of the current week"
+	(Sunday to: Saturday)
+		do: [ :aDayOfWeek | self printDayNumberOf: currentMonth for: aDayOfWeek ]		
+		separatedBy: [ stream space ]
+
+printDayNumberOf: currentMonth for: aDayOfWeek
+	"If the current date of the current month corresponds to aDayOfWeeks, prints its day number,
+	if not, leaves a space
+	This is important to leave the spaces in the first row and last row for those day of week
+	that do not have a day number related"
+	| currentDate |	
+	currentDate := self currentDateOf: currentMonth.
+	(self hasToPrint: currentDate of: currentMonth for: aDayOfWeek)
+		ifTrue: [
+			currentDate dayNumber printOn: stream length: 2 zeroPadded: false.
+			self calculateNextCurrentDateOf: currentMonth ]
+		ifFalse: [ stream space: 2 ]! !
+
+hasToPrint: aDate of: aCurrentMonth for: aDayOfWeek		
+	"Returns whether aDate is part of aCurrentMonth and its day of week is aDayOfWeek.
+	It is used to decide whether to print the date day number or leave an space"
+	^(aDate month = aCurrentMonth) and: [aDate day = aDayOfWeek]
+
+currentDateOf: currentMonth		
+	"Returns the date to print for currentMonth"
+	^monthOfYearCurrentDate at: currentMonth number
+
+calculateNextCurrentDateOf: currentMonth
+	"Changes the date to print of the currentMonth to the next date"
+	monthOfYearCurrentDate at: currentMonth number put: (self currentDateOf: currentMonth) next
+
+center: stringToCenter in: aNumberOfCharacters
+	"Prints stringToCenter centered in a line of aNumberOfCharacters total"
+	| centerStart |	
+	centerStart := aNumberOfCharacters - stringToCenter size // 2.
+	stream
+		space: centerStart;
+		nextPutAll: stringToCenter;
+		space: aNumberOfCharacters - centerStart - stringToCenter size
+
+numberOfCharactersPerLine	
+	"Returns the number of characters per line"
+	^66
+
+numberOfCharactersPerMonth	
+	"Returns the number of character per month"
+	^20

Task/Calendar/Swift/calendar.swift

@@ -0,0 +1,93 @@
+import Foundation
+
+let monthWidth = 20
+let monthGap = 2
+let dayNames = "Su Mo Tu We Th Fr Sa"
+let dateFormatter = DateFormatter()
+dateFormatter.dateFormat = "MMMM"
+
+func rpad(string: String, width: Int) -> String {
+    return string.count >= width ? string
+        : String(repeating: " ", count: width - string.count) + string
+}
+
+func lpad(string: String, width: Int) -> String {
+    return string.count >= width ? string
+        : string + String(repeating: " ", count: width - string.count)
+}
+
+func centre(string: String, width: Int) -> String {
+    if string.count >= width {
+        return string
+    }
+    let c = (width - string.count)/2
+    return String(repeating: " ", count: c) + string
+        + String(repeating: " ", count: width - string.count - c)
+}
+
+func formatMonth(year: Int, month: Int) -> [String] {
+    let calendar = Calendar.current
+    let dc = DateComponents(year: year, month: month, day: 1)
+    let date = calendar.date(from: dc)!
+    let firstDay = calendar.component(.weekday, from: date) - 1
+    let range = calendar.range(of: .day, in: .month, for: date)!
+    let daysInMonth = range.count
+    var lines: [String] = []
+    lines.append(centre(string: dateFormatter.string(from: date), width: monthWidth))
+    lines.append(dayNames)
+    var padWidth = 2
+    var line = String(repeating: " ", count: 3 * firstDay)
+    for day in 1...daysInMonth {
+        line += rpad(string: String(day), width: padWidth)
+        padWidth = 3
+        if (firstDay + day) % 7 == 0 {
+            lines.append(line)
+            line = ""
+            padWidth = 2
+        }
+    }
+    if line.count > 0 {
+        lines.append(lpad(string: line, width: monthWidth))
+    }
+    return lines
+}
+
+func printCentred(string: String, width: Int) {
+    print(rpad(string: string, width: (width + string.count)/2))
+}
+
+public func printCalendar(year: Int, width: Int) {
+    let months = min(12, max(1, (width + monthGap)/(monthWidth + monthGap)))
+    let lineWidth = monthWidth * months + monthGap * (months - 1)
+    printCentred(string: "[Snoopy]", width: lineWidth)
+    printCentred(string: String(year), width: lineWidth)
+    var firstMonth = 1
+    while firstMonth <= 12 {
+        if firstMonth > 1 {
+            print()
+        }
+        let lastMonth = min(12, firstMonth + months - 1)
+        let monthCount = lastMonth - firstMonth + 1
+        var lines: [[String]] = []
+        var lineCount = 0
+        for month in firstMonth...lastMonth {
+            let monthLines = formatMonth(year: year, month: month)
+            lineCount = max(lineCount, monthLines.count)
+            lines.append(monthLines)
+        }
+        for i in 0..<lineCount {
+            var line = ""
+            for month in 0..<monthCount {
+                if month > 0 {
+                    line.append(String(repeating: " ", count: monthGap))
+                }
+                line.append(i < lines[month].count ? lines[month][i]
+                            : String(repeating: " ", count: monthWidth))
+            }
+            print(line)
+        }
+        firstMonth = lastMonth + 1
+    }
+}
+
+printCalendar(year: 1969, width: 80)

Task/Calendar/Tcl/calendar-1.tcl

@@ -0,0 +1,75 @@
+package require Tcl 8.5
+
+# Produce information about the days in a month, without any assumptions about
+# what those days actually are.
+proc calMonthDays {timezone locale year month} {
+    set days {}
+    set moment [clock scan [format "%04d-%02d-00 12:00" $year $month] \
+	    -timezone $timezone -locale $locale -format "%Y-%m-%d %H:%M"]
+    while 1 {
+	set moment [clock add $moment 1 day]
+	lassign [clock format $moment -timezone $timezone -locale $locale \
+		-format "%m %d %u"] m d dow
+	if {[scan $m %d] != $month} {
+	    return $days
+	}
+	lappend days $moment [scan $d %d] $dow
+    }
+}
+
+proc calMonth {year month timezone locale} {
+    set dow 0
+    set line ""
+    set lines {}
+    foreach {t day dayofweek} [calMonthDays $timezone $locale $year $month] {
+	if {![llength $lines]} {lappend lines $t}
+	if {$dow > $dayofweek} {
+	    lappend lines [string trimright $line]
+	    set line ""
+	    set dow 0
+	}
+	while {$dow < $dayofweek-1} {
+	    append line "   "
+	    incr dow
+	}
+	append line [format "%2d " $day]
+	set dow $dayofweek
+    }
+    lappend lines [string trimright $line]
+}
+
+proc cal3Month {year month timezone locale} {
+    # Extract the month data
+    set d1 [lassign [calMonth $year $month $timezone $locale] t1]; incr month
+    set d2 [lassign [calMonth $year $month $timezone $locale] t2]; incr month
+    set d3 [lassign [calMonth $year $month $timezone $locale] t3]
+    # Print the header line of month names
+    foreach t [list $t1 $t2 $t3] {
+	set m [clock format $t -timezone $timezone -locale $locale -format "%B"]
+	set l [expr {10 + [string length $m]/2}]
+	puts -nonewline [format "%-25s" [format "%*s" $l $m]]
+    }
+    puts ""
+    # Print the month days
+    foreach l1 $d1 l2 $d2 l3 $d3 {
+	puts [format "%-25s%-25s%s" $l1 $l2 $l3]
+    }
+}
+
+proc cal {{year ""} {timezone :localtime} {locale en}} {
+    if {$year eq ""} {
+	set year [clock format [clock seconds] -format %Y]
+    }
+    puts [format "%40s" "-- $year --"]
+    foreach m {1 4 7 10} {
+	puts ""
+	cal3Month $year $m $timezone $locale
+    }
+}
+
+proc snoopy {} {
+    puts [format "%43s\n" {[Snoopy Picture]}]
+}
+
+snoopy
+cal

Task/Calendar/Tcl/calendar-2.tcl

@@ -0,0 +1,2 @@
+snoopy
+cal 1969

Task/Calendar/Tcl/calendar-3.tcl

@@ -0,0 +1,2 @@
+snoopy
+cal 1582 :Europe/Madrid es_ES

Task/Calendar/UNIX-Shell/calendar.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+echo "Snoopy goes here"
+cal 1969

Task/Calendar/VBScript/calendar.vb

@@ -0,0 +1,74 @@
+'call it with year, number of months per row (1,2,3,4,6) and locale ("" for default)
+docal 1969,6,""
+
+function center (s,n) x=n-len(s):center=space(x\2+(x and 1))& s & space(x\2):end function
+sub print(x) wscript.stdout.writeline x : end sub
+function iif(a,b,c) :if a then iif=b else iif =c end if : end function
+
+sub docal (yr,nmonth,sloc)
+'yr     year to print
+'nmonth number of monts side to side, allowed values :1,2,3,4,6
+'sloc   locale to use . "" uses the default
+
+dim ld(6)
+dim d(6)
+if nmonth=5 or nmonth>6 or nmonth<1 then wscript.stderr.writeline "Can't use width " & nmonth :exit sub
+
+'set the locale (names of months and weekdays plus first day of week)
+if sloc<>"" then Setlocale sloc
+
+'make a row of short weekday names to put on top of the month days
+'trim the names to 2 char and align them right
+wday=""
+for i=1 to 7
+  wday=wday &" "&right(" "& left(weekdayname(i,true,vbUseSystemDayOfWeek),2),2)
+next
+
+'print header of the calendar
+ncols=nmonth*21+(nmonth-1)*1
+print center("[Snoopy]",ncols)
+print center(yr,ncols)
+print string(ncols,"=")
+
+'row of months
+for i=1 to 12\nmonth
+  s="": s1="":esp=""
+
+  for j=1 to nmonth
+    'build header of the month row
+    s=s & esp & center(monthname(m+j),21)
+    s1=s1 & esp & wday
+
+    'get negative offset of first day of week to the weekday of day 1 of each month
+    d(j)= -weekday(dateserial(yr,m+j,1),vbUseSystemDayOfWeek)+2
+    'get last day of each month from Windows
+    ld(j)=day(dateserial(yr,m+j+1,0))
+    esp=" "
+  next
+
+  'print the row of months header (name of month and weekday names)
+  print s:  print s1
+
+  'weekday rows. makes 5 or 6 rows according to the month requiring most
+  while(d(1)<ld(1)) or (d(2)<ld(2)) or (d(3)<ld(3)) or (d(4)<ld(4))or (d(5)<ld(5)) or (d(6)<ld(6))
+    s=""
+    for j=1 to nmonth
+      'fill present week row
+      for k=1 to 7
+        'add a day number only if inside the range of days of this montg
+        s=s& right(space(3)&iif(d(j)<1 or d(j)>ld(j),"",d(j)),3)
+        d(j)=d(j)+1
+      next
+      s=s&" "
+    next
+    'print a complete row of days
+    print s
+  wend
+  'go for the next row of monts
+  m=m+nmonth
+  if i<>12\nmonth then print ""
+next
+
+'print footer
+print string(ncols,"=")
+end sub

Task/Calendar/Vedit-macro-language/calendar-1.vedit

@@ -0,0 +1,21 @@
+Buf_Switch(Buf_Free)
+Config_Tab(5,30,55)
+#9 = 1                  // first day of week: 0=Su, 1=Mo
+#3 = 3                  // number of months per line
+#2 = 1969               // year
+#1 = 1                  // starting month
+Repeat(12/#3) {
+    Repeat (#3) {
+        Buf_Switch(Buf_Free)
+        Call_File(122, "calendar.vdm", "DRAW_CALENDAR")
+        Reg_Copy_Block(10, 1, EOB_Pos, COLSET, 1, 21)
+        Buf_Quit(OK)
+        EOL Ins_Char(9)
+        #5 = Cur_Pos
+        Reg_Ins(10)
+        Goto_Pos(#5)
+        #1++
+    }
+    EOF
+    Ins_Newline(2)
+}

Task/Calendar/Vedit-macro-language/calendar-2.vedit

@@ -0,0 +1 @@
+Config_Tab(22)

Task/Calendar/Visual-Basic-.NET/calendar-1.vb

@@ -0,0 +1,9 @@
+Option Compare Binary
+Option Explicit On
+Option Infer On
+Option Strict On
+
+Imports System.Globalization
+Imports System.Text
+Imports System.Runtime.InteropServices
+Imports System.Runtime.CompilerServices

Task/Calendar/Visual-Basic-.NET/calendar-2.vb

@@ -0,0 +1,38 @@
+Module ArgHelper
+    ReadOnly _ArgDict As New Dictionary(Of String, String)()
+
+    Delegate Function TryParse(Of T, TResult)(value As T, <Out> ByRef result As TResult) As Boolean
+
+    Sub InitializeArguments(args As String())
+        For Each item In args
+            item = item.ToUpperInvariant()
+
+            If item.Length > 0 AndAlso item(0) <> """"c Then
+                Dim colonPos = item.IndexOf(":"c, StringComparison.Ordinal)
+
+                If colonPos <> -1 Then
+                    ' Split arguments with colons into key(part before colon) / value(part after colon) pairs.
+                    _ArgDict.Add(item.Substring(0, colonPos), item.Substring(colonPos + 1, item.Length - colonPos - 1))
+                End If
+            End If
+        Next
+    End Sub
+
+    Sub FromArgument(Of T)(
+            key As String,
+            <Out> ByRef var As T,
+            getDefault As Func(Of T),
+            tryParse As TryParse(Of String, T),
+            Optional validate As Predicate(Of T) = Nothing)
+
+        Dim value As String = Nothing
+        If _ArgDict.TryGetValue(key.ToUpperInvariant(), value) Then
+            If Not (tryParse(value, var) AndAlso (validate Is Nothing OrElse validate(var))) Then
+                Console.WriteLine($"Invalid value for {key}: {value}")
+                Environment.Exit(-1)
+            End If
+        Else
+            var = getDefault()
+        End If
+    End Sub
+End Module

Task/Calendar/Visual-Basic-.NET/calendar-3.vb

@@ -0,0 +1,284 @@
+Module Program
+    Sub Main(args As String())
+        Dim dt As Date
+        Dim columns, rows, monthsPerRow As Integer
+        Dim vertStretch, horizStretch, resizeWindow As Boolean
+
+        InitializeArguments(args)
+        FromArgument("date", dt, Function() New Date(1969, 1, 1), AddressOf Date.TryParse)
+        FromArgument("cols", columns, Function() 80, AddressOf Integer.TryParse, Function(v) v >= 20)
+        FromArgument("rows", rows, Function() 43, AddressOf Integer.TryParse, Function(v) v >= 0)
+        FromArgument("ms/row", monthsPerRow, Function() 0, AddressOf Integer.TryParse, Function(v) v <= 12 AndAlso v <= columns \ 20)
+        FromArgument("vstretch", vertStretch, Function() True, AddressOf Boolean.TryParse)
+        FromArgument("hstretch", horizStretch, Function() True, AddressOf Boolean.TryParse)
+        FromArgument("wsize", resizeWindow, Function() True, AddressOf Boolean.TryParse)
+
+        ' The scroll bar in command prompt seems to take up part of the last column.
+        If resizeWindow Then
+            Console.WindowWidth = columns + 1
+            Console.WindowHeight = rows
+        End If
+
+        If monthsPerRow < 1 Then monthsPerRow = Math.Max(columns \ 22, 1)
+
+        For Each row In GetCalendarRows(dt:=dt, width:=columns, height:=rows, monthsPerRow:=monthsPerRow, vertStretch:=vertStretch, horizStretch:=horizStretch)
+            Console.Write(row)
+        Next
+    End Sub
+
+    Iterator Function GetCalendarRows(
+            dt As Date,
+            width As Integer,
+            height As Integer,
+            monthsPerRow As Integer,
+            vertStretch As Boolean,
+            horizStretch As Boolean) As IEnumerable(Of String)
+
+        Dim year = dt.Year
+        Dim calendarRowCount As Integer = CInt(Math.Ceiling(12 / monthsPerRow))
+        ' Make room for the three empty lines on top.
+        Dim monthGridHeight As Integer = height - 3
+
+        Yield "[Snoopy]".PadCenter(width) & Environment.NewLine
+        Yield year.ToString(CultureInfo.InvariantCulture).PadCenter(width) & Environment.NewLine
+        Yield Environment.NewLine
+
+        Dim month = 0
+        Do While month < 12
+            Dim rowHighestMonth = Math.Min(month + monthsPerRow, 12)
+
+            Dim cellWidth = width \ monthsPerRow
+
+            ' Special case when displaying only one calendar cell in a row to make 20-wide work. Adds padding between cells otherwise.
+            Dim cellContentWidth = If(monthsPerRow = 1, cellWidth, (cellWidth * 19) \ 20)
+
+            Dim cellHeight = monthGridHeight \ calendarRowCount
+            Dim cellContentHeight = (cellHeight * 19) \ 20
+
+            ' Creates a month cell for the specified month (1-12).
+            Dim getMonthFrom =
+                Function(m As Integer) BuildMonth(
+                    dt:=New Date(dt.Year, m, 1),
+                    width:=cellContentWidth,
+                    height:=cellContentHeight,
+                    vertStretch:=vertStretch,
+                    horizStretch:=horizStretch).Select(Function(x) x.PadCenter(cellWidth))
+
+            ' The months in this row of the calendar.
+            Dim monthsThisRow As IEnumerable(Of IEnumerable(Of String)) =
+                Enumerable.Select(Enumerable.Range(month + 1, rowHighestMonth - month), getMonthFrom)
+
+            Dim calendarRow As IEnumerable(Of String) =
+                Interleaved(
+                    monthsThisRow,
+                    useInnerSeparator:=False,
+                    useOuterSeparator:=True,
+                    outerSeparator:=Environment.NewLine)
+
+            Dim en = calendarRow.GetEnumerator()
+            Dim hasNext = en.MoveNext()
+            Do While hasNext
+
+                Dim current As String = en.Current
+
+                ' To maintain the (not strictly needed) contract of yielding complete rows, keep the newline after
+                ' the calendar row with the last terminal row of the row.
+                hasNext = en.MoveNext()
+                Yield If(hasNext, current, current & Environment.NewLine)
+            Loop
+
+            month += monthsPerRow
+        Loop
+    End Function
+
+    ''' <summary>
+    ''' Interleaves the elements of the specified sub-sources by making successive passes through the source
+    ''' enumerable, yielding a single element from each sub-source in sequence in each pass, optionally inserting a
+    ''' separator between elements of adjacent sub-sources and optionally a different separator at the end of each
+    ''' pass through all the sources. (i.e., between elements of the last and first source)
+    ''' </summary>
+    ''' <typeparam name="T">The type of the elements of the sub-sources.</typeparam>
+    ''' <param name="sources">A sequence of the sequences whose elements are to be interleaved.</param>
+    ''' <param name="useInnerSeparator">Whether to insert <paramref name="useInnerSeparator"/> between the elements ofadjacent sub-sources.</param>
+    ''' <param name="innerSeparator">The separator between elements of adjacent sub-sources.</param>
+    ''' <param name="useOuterSeparator">Whether to insert <paramref name="outerSeparator"/> between the elements of the last and first sub-sources.</param>
+    ''' <param name="outerSeparator">The separator between elements of the last and first sub-source.</param>
+    ''' <param name="whileAny">If <see langword="true"/>, the enumeration continues until every given subsource is empty;
+    ''' if <see langword="false"/>, the enumeration stops as soon as any enumerable no longer has an element to supply for the next pass.</param>
+    Iterator Function Interleaved(Of T)(
+            sources As IEnumerable(Of IEnumerable(Of T)),
+            Optional useInnerSeparator As Boolean = False,
+            Optional innerSeparator As T = Nothing,
+            Optional useOuterSeparator As Boolean = False,
+            Optional outerSeparator As T = Nothing,
+            Optional whileAny As Boolean = True) As IEnumerable(Of T)
+        Dim sourceEnumerators As IEnumerator(Of T)() = Nothing
+
+        Try
+            sourceEnumerators = sources.Select(Function(x) x.GetEnumerator()).ToArray()
+            Dim numSources = sourceEnumerators.Length
+            Dim enumeratorStates(numSources - 1) As Boolean
+
+            Dim anyPrevIters As Boolean = False
+            Do
+                ' Indices of first and last sub-sources that have elements.
+                Dim firstActive = -1, lastActive = -1
+
+                ' Determine whether each sub-source that still have elements.
+                For i = 0 To numSources - 1
+                    enumeratorStates(i) = sourceEnumerators(i).MoveNext()
+                    If enumeratorStates(i) Then
+                        If firstActive = -1 Then firstActive = i
+                        lastActive = i
+                    End If
+                Next
+
+                ' Determine whether to yield anything in this iteration based on whether whileAny is true.
+                ' Not yielding anything this iteration implies that the enumeration has ended.
+                Dim thisIterHasResults As Boolean = If(whileAny, firstActive <> -1, firstActive = 0 AndAlso lastActive = numSources - 1)
+                If Not thisIterHasResults Then Exit Do
+
+                ' Don't insert a separator on the first pass.
+                If anyPrevIters Then
+                    If useOuterSeparator Then Yield outerSeparator
+                Else
+                    anyPrevIters = True
+                End If
+
+                ' Go through and yield from the sub-sources that still have elements.
+                For i = 0 To numSources - 1
+                    If enumeratorStates(i) Then
+                        ' Don't insert a separator before the first element.
+                        If i > firstActive AndAlso useInnerSeparator Then Yield innerSeparator
+                        Yield sourceEnumerators(i).Current
+                    End If
+                Next
+            Loop
+
+        Finally
+            If sourceEnumerators IsNot Nothing Then
+                For Each en In sourceEnumerators
+                    en.Dispose()
+                Next
+            End If
+        End Try
+    End Function
+
+    ''' <summary>
+    ''' Returns the rows representing one month cell without trailing newlines. Appropriate leading and trailing
+    ''' whitespace is added so that every row has the length of width.
+    ''' </summary>
+    ''' <param name="dt">A date within the month to represent.</param>
+    ''' <param name="width">The width of the cell.</param>
+    ''' <param name="height">The height.</param>
+    ''' <param name="vertStretch">If <see langword="true" />, blank rows are inserted to fit the available height.
+    ''' Otherwise, the cell has a constant height of </param>
+    ''' <param name="horizStretch">If <see langword="true" />, the spacing between individual days is increased to
+    ''' fit the available width. Otherwise, the cell has a constant width of 20 characters and is padded to be in
+    ''' the center of the expected width.</param>
+    Iterator Function BuildMonth(dt As Date, width As Integer, height As Integer, vertStretch As Boolean, horizStretch As Boolean) As IEnumerable(Of String)
+        Const DAY_WDT = 2 ' Width of a day.
+        Const ALLDAYS_WDT = DAY_WDT * 7 ' Width of al ldays combined.
+
+        ' Normalize the date to January 1.
+        dt = New Date(dt.Year, dt.Month, 1)
+
+        ' Horizontal whitespace between days of the week. Constant of 6 represents 6 separators per line.
+        Dim daySep As New String(" "c, Math.Min((width - ALLDAYS_WDT) \ 6, If(horizStretch, Integer.MaxValue, 1)))
+        ' Number of blank lines between rows.
+        Dim vertblankCount = If(Not vertStretch, 0, (height - 8) \ 7)
+
+        ' Width of each day * 7 days in one row + day separator length * 6 separators per line.
+        Dim blockWidth = ALLDAYS_WDT + daySep.Length * 6
+
+        ' The whitespace at the beginning of each line.
+        Dim leftPad As New String(" "c, (width - blockWidth) \ 2)
+        ' The whitespace for blank lines.
+        Dim fullPad As New String(" "c, width)
+
+        ' Lines are "staged" in the stringbuilder.
+        Dim sb As New StringBuilder(leftPad)
+        Dim numLines = 0
+
+        ' Get the current line so far form the stringbuilder and begin a new line.
+        ' Returns the current line and trailing blank lines used for vertical padding (if any).
+        ' Returns empty enumerable if the height requirement has been reached.
+        Dim EndLine =
+         Function() As IEnumerable(Of String)
+             Dim finishedLine As String = sb.ToString().PadRight(width)
+             sb.Clear()
+             sb.Append(leftPad)
+
+             ' Use an inner iterator to prevent lazy execution of side effects of outer function.
+             Return If(numLines >= height,
+                 Enumerable.Empty(Of String)(),
+                 Iterator Function() As IEnumerable(Of String)
+                     Yield finishedLine
+                     numLines += 1
+
+                     For i = 1 To vertblankCount
+                         If numLines >= height Then Return
+                         Yield fullPad
+                         numLines += 1
+                     Next
+                 End Function())
+         End Function
+
+        ' Yield the month name.
+        sb.Append(PadCenter(dt.ToString("MMMM", CultureInfo.InvariantCulture), blockWidth))
+        For Each l In EndLine()
+            Yield l
+        Next
+
+        ' Yield the header of weekday names.
+        Dim weekNmAbbrevs = [Enum].GetNames(GetType(DayOfWeek)).Select(Function(x) x.Substring(0, 2))
+        sb.Append(String.Join(daySep, weekNmAbbrevs))
+        For Each l In EndLine()
+            Yield l
+        Next
+
+        ' Day of week of first day of month.
+        Dim startWkDy = CInt(dt.DayOfWeek)
+
+        ' Initialize with empty space for the first line.
+        Dim firstPad As New String(" "c, (DAY_WDT + daySep.Length) * startWkDy)
+        sb.Append(firstPad)
+
+        Dim d = dt
+        Do While d.Month = dt.Month
+            sb.AppendFormat(CultureInfo.InvariantCulture, $"{{0,{DAY_WDT}}}", d.Day)
+
+            ' Each row ends on saturday.
+            If d.DayOfWeek = DayOfWeek.Saturday Then
+                For Each l In EndLine()
+                    Yield l
+                Next
+            Else
+                sb.Append(daySep)
+            End If
+
+            d = d.AddDays(1)
+        Loop
+
+        ' Keep adding empty lines until the height quota is met.
+        Dim nextLines As IEnumerable(Of String)
+        Do
+            nextLines = EndLine()
+            For Each l In nextLines
+                Yield l
+            Next
+        Loop While nextLines.Any()
+    End Function
+
+    ''' <summary>
+    ''' Returns a new string that center-aligns the characters in this string by padding to the left and right with
+    ''' the specified character to a specified total length.
+    ''' </summary>
+    ''' <param name="s">The string to center-align.</param>
+    ''' <param name="totalWidth">The number of characters in the resulting string.</param>
+    ''' <param name="paddingChar">The padding character.</param>
+    <Extension()>
+    Private Function PadCenter(s As String, totalWidth As Integer, Optional paddingChar As Char = " "c) As String
+        Return s.PadLeft(((totalWidth - s.Length) \ 2) + s.Length, paddingChar).PadRight(totalWidth, paddingChar)
+    End Function
+End Module