/*
  Remember about functions running in their own private little
  universes. Every time a function is called, even if it is
  already running, a new chunk of memory is set aside for it
  to store all of its values.
  
  This program prints the sequence 13 6 3 1 0 0 1 3 6 13.
  
  When it prints the two zeros, there are five different chunks
  of memory, all for the different runs of strange that haven't
  finished yet. There are 5 different versions of n, one for
  each.
*/

#include "library.h"

void strange(int n)
{ print(n);
  print(" ");
  if (n>0)
    strange(n/2);
  print(n);
  print(" "); }

void main()
{ strange(13); }