import "io"

let twotimes(x) be
{ let prev;
  if x = 0 then resultis 0;
  prev := twotimes(x-1);
  resultis prev+2 }

/*
   The point of this program is that it will use just as much
   stack memory as I want. Whatever the value of a is, it will
   use just over 5*a words of stack space
*/

let start() be
{ let a, b;
  a := 500;
  b := twotimes(a);
  out("twotimes(%d) = %d\n", a, b) }