Mencari bilangan Prima

Program Bilangan_Prima;

uses crt;

var a,b,c,d,e:longint;

procedure deret_prima(x,y,z:longint);

begin

writeln('2':7);

for x:=3 to z do

begin

for y:= 2 to x-1 do

begin

if x mod y = 0 then begin

d:=x ; end else begin e:=x; end;end;

if x=d then

begin

y:= x-1;

end else

writeln(e:7);

end;

end;

begin

clrscr;

write('bilangan prima sampai berapa? '); readln(c);

deret_prima(a,b,c);

readln;

end.