利用指针交换两个值（C语言）

# include <stdio.h>

void exchange(int * p, int * q)
{
    int t ;
    t = *p ;
    *p = *q ;
    *q = t;
}


int main(void)
{
    int a = 3;
    int b = 5;

    exchange(&a, &b);
    printf("a= %d , b = %d", a, b);
    
    return 0;
}