一道面试题

#include <stdio.h>

#define func1(A,B)  A=A+B;  B=A-B;  A=A-B;

int func2(int A, int B)
{
int c = 0;

c = A;
A = B;
B = A;
}

int main(int argc, char * argv[])
{
int a = 3, b =5;

func1(a,b);
printf("a = %d b = %d\n", a, b);

func2(a,b);
printf("a = %d b = %d\n", a, b);
}

a = 5 b = 3
a = 5 b = 3