#include <stdio.h>// SWAP(x, y)				交换x,y的值
#define SWAP(x, y) \(y) = (x) + (y); \(x) = (y) - (x); \(y) = (y) - (x);int main()
{int a = 3-2, b = 5*8;SWAP(a, b);printf("%d, %d\n", a, b);return 0;
}

运行结果：

40, 1