Contoh Program Himpunan

uses wincrt;
var
 a,b,c,d,e,f,g,h: integer;
 k,w :char;
 pilih: integer;
procedure input;
begin
clrscr;
 write('Masukan Nilai n(A) :');readln(a);
 write('Masukan Nilai n(B) :');readln(b);
 write('Masukan Nilai n(C) :');readln(c);
 write('Masukan Nilai n(A n B) :');readln(d);
 write('Masukan Nilai n(B n C) :');readln(e);
 write('Masukan Nilai n(A n C) :');readln(f);
 write('Masukan Nilai n(A n B n C) :');readln(g);
end;
procedure hitung;
begin
h:=a+b+c-d-e-f+g;
 if h<=0 then
 else writeln('error');
end;

procedure output;
begin
      k:='y';
      while (k='y') or (k='Y') do
          begin
          clrscr;


          write('n(A u B u C)=n(A)+n(B)+n(C)-n(A n B)-n(B n C)-n(A n C)+n(A n B n C)');writeln;
          write(h,'=',a,'+',b,'+',c,'-',d,'-',e,'-',f,'+',g);writeln;
          writeln('pilihan: ');
          writeln('A. n(A)');
          writeln('B. n(B)');
          writeln('C. n(C)');
          writeln('D. n(A n B)');
          writeln('E. n(B n C)');
          writeln('F. n(A n C)');
          writeln('G. n(A n B n C)');
          writeln('---------------');
          write('Masukkan Pilihan: ');readln(w);
          case w of
          'A','a':begin
                  writeln(a,'=',h,'-',b,'-',c,'+',d,'+',e,'+',f,'-',g);
               
          end;
          'B','b':begin
                 writeln(b,'=',h,'-',a,'-',c,'+',d,'+',e,'+',f,'-',g);
               
          end;
          'C','c':begin
                 writeln(c,'=',h,'-',a,'-',b,'+',d,'+',e,'+',f,'-',g);
                
          end;
          'D','d':begin
                 writeln(d,'=',a,'+',b,'+',c,'-',e,'-',f,'+',g,'-',h);
                
          end;
          'E','e':begin
                 writeln(e,'=',a,'+',b,'+',c,'-',d,'-',f,'+',g,'-',h);
                
          end;
          'F','f':begin
                 writeln(f,'=',a,'+',b,'+',c,'-',d,'-',e,'+',g,'-',h);
                

                 end;
          'G','g':begin
                 writeln(g,'=',h,'-',a,'-',b,'-',c,'+',d,'+',e,'+',f);
                

                 end;
          else writeln('Salah Input!!');
          write('Ulang (y/t):');readln(k);
          end;
          readln;
          end;

     end;
begin
   repeat
      clrscr;
      writeln(' MENU UTAMA  ');
      writeln('=============');
      writeln(' 1. INPUT    ');
      writeln(' 2. OUTPUT   ');
      writeln('=============');
      write('pilih <0 :keluar> : '); readln(pilih);
      case pilih of

      1 : input;
      2 :
          begin
           hitung;
              output;

          end
        end;
        until pilih=0;
        end.
end.
end.