/**
 * swap.c - the standard C swap routine.
 */

#include <stdio.h>
#include <stdlib.h>

void
swap (int *ap, int *bp)
{
  int temp = *ap;
  *ap = *bp;
  *bp = temp;
} // swap

#ifdef UNIT_TEST
int errors;

void 
utest_swap ()
{
  int x = 1;
  int y = 2;

  swap (&x, &y);
  if ((x != 2) || (y != 1))
    {
      ++errors;
      printf ("Failed to correctly swap x and y.\n");
    }
 
  x = 0;
  swap (&x, &x);
  if (x != 0)
    {
      ++errors;
      printf ("Failed to correctly swap x with itself.\n");
    }
} // utest_swap

int
main ()
{
  utest_swap ();
  if (errors)
    printf ("%d errors encountered.\n", errors);

  return errors;
} // main ()
#endif // UNIT_TEST