结构体struct

#include<iostream>
using namespace std;
struct point 
{
	int x,y;
	point(int x=0,int y=0):x(x),y(y){}  //构造函数初始化成员变量 
};
point operator + (const point &a,const point &b)//重载操作符 + 
{
	return point(a.x+b.x,a.y+b.y);
}
ostream &operator << (ostream &out,const point &p)//重载操作符 << 
{
	out<<"("<<p.x<<","<<p.y<<")";
	return  out;
}
int main()
{
	point a,b(1,2);
	a.x=3;
	cout<<a+b<<endl;
}

代码摘自刘汝佳算法竞赛入门经典（第二版）