Listing 4: ptr1.c

/*
  ptr1.c

  B.McMullin
  30th April 1996.
*/

#include <stdio.h>

void main(void)
{
  int i, j, k,
      *p, *q, *r, *s,
      **t, **u, **v;

  i = 0;
  p = &k;
  q = &i;
  r = &j;
  s = r;
  t = &q;
  u = &p;
  v = &s;
  j = *q;
  k = j;

  while ((j <= 15) && (j >= -15))
  {
    j++;
    s = r;
    r = q;
    q = p;
    p = s;
    v = u;
    u = t;
    t = v;
    (**t)--;
    (**u)++;
  }

  /* What are the final values of i, j, k? */

/*
  printf("i = %d\n", i);
  printf("j = %d\n", j);
  printf("k = %d\n", k);
*/
}