三种运算符重载，每个至少实现一个运算符的重载 

#include <iostream>using namespace std;class Person
{friend const Person operator- (const Person &L, const Person &R);friend bool operator<(const Person &L,const Person &R);friend Person &operator/=(Person &L,const Person &R);
private:int a;int b;
public:Person(){}Person(int a, int b):a(a),b(b){}//    //成员函数实现-号运算符重载
//   const Person operator- (const Person &R) const
//   {
//       Person temp;
//       temp.a = a - R.a;
//       temp.b = b - R.b;
//       return temp;
//   }//成员函数实现<号运算符重载
//bool operator<(const Person &R) const
//{
//    if(a < R.a && b < R.b)
//    {
//        return true;
//    }else
//    {
//        return false;
//    }
//}//局部函数实现/=号运算符重载
//    Person &operator/=(const Person &R)
//    {
//        a /= R.a;
//        b /= R.b;
//        return  *this;
//    }void show(){cout << "a= " << a << "  " << "b= " << b << endl;}
};//全局函数实现-号运算符重载
const Person operator-(const Person &L,const Person &R)
{Person temp;temp.a = L.a - R.a;temp.b = L.b - R.b;return temp;
}//全局函数实现<号运算符重载
bool operator<(const Person &L,const Person &R)
{if(L.a < R.a && L.b < R.b){return true;}else{return false;}
}//全局函数实现/=号运算符重载
Person &operator/=(Person &L,const Person &R)
{L.a /= R.a;L.b /= R.b;return  L;
}int main()
{Person p1(20,10);Person p2(10,5);Person p3 = p1 - p2;p3.show();if( p3 < p1){cout << "p3 < p1" << endl;}p1 /= p3;p1.show();return 0;
}

效果图：