Initial data commit

Task/Set/Liberty-BASIC/set.basic

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+A$ ="red hot chili peppers rule OK"
+B$ ="lady in red"
+
+print " New set, in space-separated form. Extra spaces and duplicates will be removed. "
+input newSet$
+ newSet$  =trim$(           newSet$)
+ newSet$  =stripBigSpaces$( newSet$)
+ newSet$  =removeDupes$(    newSet$)
+print " Set stored as the string '"; newSet$; "'"
+
+print
+print " 'red'  is an element of '"; A$; "' is "; isAnElementOf$( "red",  A$)
+print " 'blue' is an element of '"; A$; "' is "; isAnElementOf$( "blue",  A$)
+print " 'red'  is an element of '"; B$; "' is "; isAnElementOf$( "red",  B$)
+print
+print " Union        of '"; A$; "' & '"; B$; "' is '"; unionOf$( A$, B$); "'."
+print
+print " Intersection of '"; A$; "' & '"; B$; "' is '"; intersectionOf$( A$, B$); "'."
+print
+print " Difference   of '"; A$; "' & '"; B$; "' is '"; differenceOf$( A$, B$); "'."
+print
+print " '"; A$; "' equals '";        A$; "' is "; equalSets$( A$, A$)
+print " '"; A$; "' equals '";        B$; "' is "; equalSets$( A$, B$)
+print
+print  " '"; A$; "' is a subset of '"; B$; "' is "; isSubsetOf$( A$, B$)
+print  " 'red peppers' is a subset of 'red hot chili peppers rule OK' is "; isSubsetOf$( "red peppers", "red hot chili peppers rule OK")
+
+end
+
+function removeDupes$( a$)
+    numElements =countElements( a$)
+    redim elArray$( numElements)         '   ie 4 elements are array entries 1 to 4 and 0 is spare =""
+    for m =0 to numElements
+        el$ =word$( a$, m, " ")
+        elArray$( m) =el$
+    next m
+    sort elArray$(), 0, numElements
+    b$           =""
+    penultimate$ ="999"
+    for jk =0 to numElements    '   do not use "" ( nuls) or elementsalready seen
+        if elArray$( jk) ="" then [on]
+        if elArray$( jk) <>penultimate$ then b$ =b$ +elArray$( jk) +" ": penultimate$ =elArray$( jk)
+        [on]
+    next jk
+    b$ =trim$( b$)
+    removeDupes$ =b$
+end function
+
+function stripBigSpaces$( a$)   '   copy byte by byte, but id=f a space had a preceding space, ignore it.
+    lenA =len( a$)
+    penul$ =""
+    for i =1 to len( a$)
+        c$ =mid$( a$, i, 1)
+        if c$ <>" " then
+            if penul$ <>" " then
+                b$ =b$ +c$
+            else
+                b$ =b$ +" " +c$
+            end if
+        end if
+        penul$ =c$
+    next i
+    stripBigSpaces$ =b$
+end function
+
+function countElements( a$) '   count elements repr'd by space-separated words in string rep'n.
+    if isNul$( a$) ="True" then countElements =0: exit function
+    i  =0
+    do
+        el$ =word$( a$, i +1, " ")
+        i =i +1
+    loop until el$ =""
+    countElements =i -1
+end function
+
+function isNul$( a$)    '   a nul set implies its string rep'n is length zero.
+    if a$ ="" then isNul$ ="True" else isNul$ ="False"
+end function
+
+function isAnElementOf$( a$, b$)    '   check element a$ exists in set b$.
+    isAnElementOf$ ="False"
+    i  =0
+    do
+        el$ =word$( b$, i +1, " ")
+        if a$ =el$ then isAnElementOf$ ="True"
+        i =i +1
+    loop until el$ =""
+end function
+
+function unionOf$( a$, b$)
+    i  =1
+    o$ =a$
+    do
+        w$ =word$( b$, i, " ")
+        if w$ ="" then exit do
+        if isAnElementOf$( w$, a$) ="False" then o$ =o$ +" " +w$
+        i =i +1
+    loop until w$ =""
+    unionOf$ =o$
+end function
+
+function intersectionOf$( a$, b$)
+    i  =1
+    o$ =""
+    do
+        el$ =word$( a$, i, " ")
+        if el$ ="" then exit do
+        if ( isAnElementOf$( el$, b$) ="True") and ( o$ ="")  then o$ =el$
+        if ( isAnElementOf$( el$, b$) ="True") and ( o$ <>el$) then o$ =o$ +" " +el$
+        i =i +1
+    loop until el$ =""
+    intersectionOf$ =o$
+end function
+
+function equalSets$( a$, b$)
+    if len( a$) <>len( b$) then equalSets$ ="False": exit function
+    i =1
+    do
+        el$ =word$( a$, i, " ")
+        if isAnElementOf$( el$, b$) ="False" then equalSets$ ="False": exit function
+        i =i +1
+    loop until w$ =""
+    equalSets$ ="True"
+end function
+
+function differenceOf$( a$, b$)
+    i  =1
+    o$ =""
+    do
+        el$ =word$( a$, i, " ")
+        if el$ ="" then exit do
+        if ( isAnElementOf$( el$, b$) ="False") and ( o$ ="")   then o$ =el$
+        if ( isAnElementOf$( el$, b$) ="False") and ( o$ <>el$) then o$ =o$ +" " +el$
+        i =i +1
+    loop until el$ =""
+    differenceOf$ =o$
+end function
+
+function isSubsetOf$( a$, b$)
+    isSubsetOf$ ="True"
+    i  =1
+    do
+        el$ =word$( a$, i, " ")
+        if el$ ="" then exit do
+        if ( isAnElementOf$( el$, b$) ="False") then isSubsetOf$ ="False": exit function
+        i =i +1
+    loop until el$ =""
+end function