Acest program aduna numerele introduse pana e introdus 0:
program calcsum;
var
sum : integer;
n : integer;
begin
sum := 0;
write('Enter a number: ');
readln(n);
while n <> 0 do
begin
sum := sum + n;
write('Enter a number: ');
readln(n);
end;
writeln('The sum is ', sum);
end.
E destul de simplu.