#include <stdio.h>

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

main(int argc, char ** argv)
{  int x,y;
   x = 1;
   y = 2;
   swap(x,y);
   printf("x: %d, y: %d\n",x,y);
}