关于宏定义

#include<iostream>
using namespace std;
#define M 10*10
#define min(a,b) ((a) < (b) ? (a) : (b))   //宏在变量被调用的时候是替换的
const int size = 10;
int ia[size];


int main() {
int elem_cnt = 0;
int *p = &ia[0];
// 计数数组元素的个数
while (min(p++, &ia[size]) != &ia[size])/*min(p++, &ia[size])被替换成P++<&ia[size]?p++:&ia[size]，所以elem_cnt结果会为5*/
++elem_cnt;
cout << "elem_cnt : " << elem_cnt
<< "\texpecting: " << size << endl;
return 0;

}

结果为elem_cnt : 5 expecting: 10