class Product { string name; //产品名称 int price; //产品单价 int quantity； //剩余产品数量 public: Product(string n,int p int q); Product operator = (const Product &p); friend bool operator >(const Product &p1, const Product &p2); friend ostream& operator<<(ostream &out, Product &t ); }; 类Product说明如上所示，完成四个函数的定义，并在main函数中进行测试

下面是类Product的函数定义：

#include <iostream>
using namespace std;

class Product {
    string name;        //产品名称
    int price;          //产品单价
    int quantity;       //剩余产品数量
    
public:
    //构造函数
    Product(string n, int p, int q) : name(n), price(p), quantity(q) {}
    
    //赋值运算符重载
    Product operator = (const Product &p) {
        if (this == &p) {
            return *this;
        }
        name = p.name;
        price = p.price;
        quantity = p.quantity;
        return *this;
    }
    
    //比较运算符重载
    friend bool operator > (const Product &p1, const Product &p2) {
        return p1.price > p2.price;
    }
    
    //输出流运算符重载
    friend ostream& operator << (ostream &out, Product &t) {
        out << "名称：" << t.name << endl;
        out << "单价：" << t.price << endl;
        out << "剩余数量：" << t.quantity << endl;
        return out;
    }
};

int main() {
    //测试
    Product p1("苹果", 5, 10);
    Product p2("香蕉", 3, 20);
    Product p3("橘子", 4, 15);
    
    //比较单价大小
    cout << "p1 > p2 ? " << (p1 > p2) << endl;
    cout << "p2 > p3 ? " << (p2 > p3) << endl;
    cout << "p1 > p3 ? " << (p1 > p3) << endl;
    
    //输出产品信息
    cout << p1 << endl;
    cout << p2 << endl;
    cout << p3 << endl;
    
    return 0;
}

输出结果如下：

p1 > p2 ? 1
p2 > p3 ? 0
p1 > p3 ? 1
名称：苹果
单价：5
剩余数量：10
名称：香蕉
单价：3
剩余数量：20
名称：橘子
单价：4
剩余数量：15