#include <iostream>
using namespace std;
int main(void)
{
int x = 3;
//定义引用，y是x的引用
int &y=x;
//打印x和y的值
cout << x << endl;
cout << y << endl;
//修改y的值
y = 3;
//再次打印x和y的值
cout << x << "," << y << endl;
return 0;
}
