03.txt

C++扩展pl0编译

var sum,a,b;
procedure p;
  begin
    sum:=0;
    for a:=1 to b do
      sum+=a;
  end;

begin
  read(b);
  while b<>0 do
    begin
      call p;
      write(sum);
      read(b);
    end
end.