/* Program 11-9

   More on pointers and functions */

void exchange (int *pointer1, int *pointer2)
 {
  int temp;

  temp = *pointer1;
  *pointer1 = *pointer2;
  *pointer2 = temp;
 }

main ()
{
 int i1 = -5, i2 = 66, *p1 = &i1, *p2 = &i2;

 printf ("i1 = %d, i2 = %d\n", i1, i2);

 exchange (p1, p2);
 printf ("i1 = %d, i2 = %d\n", i1, i2);

 exchange (&i1, &i2);
 printf ("i1 = %d, i2 = %d\n", i1, i2);
}


/* Program Output

i1 = -5, i2 = 66
i1 = 66, i2 = -5
i1 = -5, i2 = 66

*/