/************************/
/* swap.c				*/
/* Weiwei Chen 07/27/12	*/
/************************/
#include <stdio.h>

int main(void)
{
	int x1, y1, t;
	int x2, y2;

	x1 = 27;
	y1 = 42;	
	printf("Before swapping: x1 = %d, y1 = %d \n", x1, y1);
	t = x1;
	x1 = y1;
	y1 = t;
	printf("After swapping: x1 = %d, y1 = %d \n", x1, y1);	
	
	x2 = 18;
	y2 = 32;
	printf("Before swapping: x2 = %d, y2 = %d \n", x2, y2);
	x2 = x2 + y2;
	y2 = x2 - y2;
	x2 = x2 - y2;
	printf("After swapping: x2 = %d, y2 = %d \n", x2, y2);


	return 0;
}