{ A simple test of input, output, and expressions. }
var
  sum: integer;
  x: integer;
begin
  sum := 0;
  x := 1; { Hack }
  write('Enter a series of integers (one per line) and I will compute their sum.');
  while (x <> 0) do
    begin
      write('Next number: ');
      read(x);
      sum := sum + x;
    end;
  write('The sum is: ');
  writeln(sum);
end
{ That's it! }