program10-9.c

// More on pointers and functions

#include <stdio.h>

void exchange(int * const pint1, int * const pint2)
{
    int temp;

  temp = *pint1;
    *pint1 = *pint2;
    *pint2 = temp;
}

int main(void)
{
    void exchange(int * const pint1, int * const pint2);
    int i1 = -5, i2 = 66, *p1 = &i1, *p2 = &i2;

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

  exchange(p1, p2);

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

  exchange(&i1, &i2);

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

  return 0;
}