第八周 项目一（2）：实现复数类中的运算符重载（友元函数）

问题及代码：

/** Copyright (c) 2015,烟台大学计算机学院* All rights reserved.* 文件名称：test.cpp* 作者：李楠* 完成日期：2015年4月22日* 版本号：v1.0** 问题描述：请用类的友元函数，而不是成员函数，再次完成上面提及的运算符的重载；* 输入描述：略* 程序输出：略*/#include<iostream>using namespace std;class Complex{public:    Complex(){real=0;imag=0;}    Complex(double r,double i){real=r; imag=i;}    friend Complex operator+(const Complex &c1,const Complex &c2);    friend Complex operator-(const Complex &c1,const Complex &c2);    friend Complex operator*(const Complex &c1,const Complex &c2);    friend Complex operator/(const Complex &c1,const Complex &c2);    void display();private:    double real;    double imag;};//下面定义成员函数Complex operator+(const Complex &c1,const Complex &c2){    Complex c;    c.real=c1.real+c2.real;    c.imag=c1.imag+c2.imag;    return c;}Complex operator-(const Complex &c1,const Complex &c2){    Complex c;    c.real=c1.real-c2.real;    c.imag=c1.imag-c2.imag;    return c;}Complex operator*(const Complex &c1,const Complex &c2){    Complex c;    c.real=c1.real*c2.real-c1.imag*c2.imag;    c.imag=c1.imag*c2.real+c1.real*c2.imag;    return c;}Complex operator/(const Complex &c1,const Complex &c2){    Complex c;    c.real=(c1.real*c2.real+c1.imag*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag);    c.imag=(c1.imag*c2.real-c1.real*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag);    return c;}void Complex::display(){    cout<<"("<<real<<","<<imag<<"i)"<<endl;}//下面定义用于测试的main()函数int main(){    Complex c1(3,4),c2(5,-10),c3;    cout<<"c1=";    c1.display();    cout<<"c2=";    c2.display();    c3=c1+c2;    cout<<"c1+c2=";    c3.display();    c3=c1-c2;    cout<<"c1-c2=";    c3.display();    c3=c1*c2;    cout<<"c1*c2=";    c3.display();    c3=c1/c2;    cout<<"c1/c2=";    c3.display();    return 0;}

运行结果：

 

知识点总结：

这里类的友元函数需要两个变量…

学习心得：

写得很开心~