Data Update

Task/Sisyphus-sequence/Free-Pascal-Lazarus/sisyphus-sequence.pas

@@ -0,0 +1,132 @@
+program Sisyphus;
+{$IFDEF FPC}
+  {$MODE DELPHI}{$Coperators ON}{$Optimization ON}
+{$ENDIF}
+{$IFDEF WINDOWS}
+  {$APPTYPE CONSOLE}
+{$ENDIF}
+uses
+  sysutils,
+  primsieve;// https://rosettacode.org/wiki/Extensible_prime_generator#Pascal
+
+function CommatizeUint64(num:Uint64):AnsiString;
+var
+   fromIdx,toIdx :Int32;
+Begin
+  str(num,result);
+  fromIdx := length(result);
+  toIdx := fromIdx-1;
+  if toIdx < 3 then
+    exit;
+
+  toIdx := 4*(toIdx DIV 3)+toIdx MOD 3 +1 ;
+  setlength(result,toIdx);
+  repeat
+    result[toIdx]   := result[FromIdx];
+    result[toIdx-1] := result[FromIdx-1];
+    result[toIdx-2] := result[FromIdx-2];
+    result[toIdx-3] := ',';
+    dec(toIdx,4);
+    dec(FromIdx,3);
+  until FromIdx<=3;
+end;
+
+procedure OutOne(n,count: Uint64);
+Begin
+  write(n:5);
+  If count mod 10 = 0 then
+    writeln;
+end;
+
+procedure OutRes(n,count,p:Uint64);
+Begin
+  writeln(CommatizeUint64(n):15, ' found after ',CommatizeUint64(count):12,' iterations: Max prime ',CommatizeUint64(p):12);
+end;
+
+procedure CheckSmall;
+var
+  CntOccurence : array[0..255] of byte;
+  n,count,p,limit : Uint64;
+begin
+  InitPrime;
+  writeln('The first 100 members of the Sisyphus sequence');
+  fillchar(CntOccurence,SizeOf(CntOccurence),#0);
+  n := 1;
+  count := 1;
+  Limit := 1000;
+  CntOccurence[n] := 1;
+
+  repeat
+    if count <= 100 then
+    Begin
+      OutOne(n,count);
+      if count = 100 then
+        writeln;
+   end;
+
+   if n AND 1 = 0 then
+     n := n shr 1
+   else
+   begin
+     p := nextprime;
+     n += p;
+   end;
+   count+= 1;
+   iF n < 255 then
+     inc(CntOccurence[n]);
+
+   if (count = Limit) then
+   Begin
+     OutRes(n,count,p);
+     Limit *= 10;
+   end;
+  until Limit > 100*1000*1000;
+
+  writeln(#10,'Not found numbers below 250 after ',CommatizeUint64(count),' iterations');
+  p := 0;// maximum
+  For n := 1 to 250 do
+  begin
+    if CntOccurence[n] = 0 then
+      write(n:4);
+    if p < CntOccurence[n] then
+      p := CntOccurence[n];
+  end;
+  Writeln;
+
+  writeln(#10,'Mostly found numbers below 250 after ',CommatizeUint64(count),' iterations');
+  For n := 1 to 250 do
+    if CntOccurence[n] = p then
+      write(n:4);
+  Writeln(' found ',p,' times');
+end;
+
+procedure Check;
+var
+  n,count,target,p : Uint64;
+begin
+  InitPrime;
+  n := 1;
+  count := 1;
+  Target := 36;
+  repeat
+    if n AND 1 = 0 then
+      n := n shr 1
+    else
+    begin
+      p := nextprime;
+      n += p;
+    end;
+    count+= 1;
+    if (n = target) then
+    Begin
+      OutRes(n,count,p);
+      BREAK;
+    end;
+  until false;
+end;
+
+BEGIN
+  CheckSmall;
+  writeln;
+  CHECK;
+end.

Task/Sisyphus-sequence/Ruby/sisyphus-sequence.rb

@@ -0,0 +1,29 @@
+require 'prime'
+
+prime_gen = Prime.each
+cur_prime = nil
+sisyphi   = Enumerator.produce(1) {|n| n.even? ? n/2 : n += (cur_prime = prime_gen.next)}
+
+sisyphi.first(100).each_slice(10){|s| puts "%4d"*s.size % s }
+
+puts
+prime_gen.rewind
+counter = Hash.new(0)
+count_until = 250
+idx   = 1000
+limit = 100_000_000
+sisyphi.with_index(1) do |n, i|
+  counter[n] += 1 if n < count_until
+  if i == idx then
+    puts "element %11d is %11d, with prime %11d" % [i, n, cur_prime]
+    break if idx >= limit
+    idx *= 10
+  end
+end
+
+puts "\nThese numbers under #{count_until} do not occur in the first #{limit} terms:"
+puts ((1...count_until).to_a - counter.keys).join ", "
+
+freq, nums = counter.group_by{|k, v| v}.max
+puts "\nThese numbers under #{count_until} occur most frequent (#{freq} times) in the first #{limit} terms:"
+puts nums.map(&:first).sort.join(", ")