{I was inspired to write this program while I was lying in bed trying
 to fall asleep.  I suddenly had this great idea and here it is!
 }

program findprimes(input, output);

uses
  crt;

type
  LPointer = ^List;
  List = record
    Number: integer;
    link: LPointer;
  end;

var
  Head: LPointer;
  I, numprimes: integer;

Procedure InitList;
begin
  new(Head);
  Head^.Number := 2;
  Head^.Link := nil;
end;

Procedure AddOne(Num: integer; AfterMe: LPointer);
var
  PNew: LPointer;
begin
  new(PNew);
  PNew^.Number := num;
  PNew^.Link := nil;
  AfterMe^.Link := Pnew;
end;

Procedure IsPrime(I: integer; TestAgainst: LPointer);
var
  temp: boolean;

begin
  temp := ((I mod TestAgainst^.Number) = 0);     {see if it goes in evenly}
  If temp = true then
  begin
  {  Writeln(I, ': false (', TestAgainst^.Number, ')');
  }end
  else
  begin
    if (TestAgainst^.Link = nil) {or (TestAgainst^.Number > sqrt(i) + 1)} then
    begin
      Inc(NumPrimes);
      Writeln(I, ': true');
      AddOne(I, TestAgainst);       {problem here}
    end
    else
     begin
      IsPrime(I, TestAgainst^.Link);
    end;
  end;

end;

Begin
  ClrScr;
  InitList;
  For I := 2 to 100 do
  begin
    IsPrime(I, Head);
    If ((I mod 24) = 0) then ReadKey;
    end;
  writeln('Total: ', NumPrimes);
  Readkey;
end.