测试:
#include <iostream>
using namespace std;
int main(){
int i =0;
cout << "初始化 i == " << i << endl;
cout << "i++ == " << i++ << endl;
cout << "经过 i++ 运算,此时的i: " << i << endl;
cout << endl;
i = 0; // i 重置为0
cout << "初始化 i == " << i << endl;
cout << "++i == " << ++i << endl;
cout << "经过 ++i 运算,此时的i: " << i << endl;
}