/* swap.c */
#include <stdio.h>

void swap(int *a, int *b)
{
  int t;
  t = *a; *a = *b; *b = t;
}

int main(void)
{
  int x=3, y=4;
  swap(&x,&y);
  printf("%d %d\n",x,y);
  return 0;
}