八周 项目 1.2 用友元函数完成复数中的运算符重载

/** 程序的版权和版本声明部分:* Copyright (c) 2013, 烟台大学计算机学院* All rights reserved.* 文件名称：test.cpp* 作    者：赵加响* 完成日期：2014年 4月 15日* 输入描述：* 程序输出：* 问题分析：略* 算法设计：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+(Complex &c1,Complex &c2);    friend Complex operator-(Complex &c1,Complex &c2);    friend Complex operator*(Complex &c1,Complex &c2);    friend Complex operator/(Complex &c1,Complex &c2);    void display();private:    double real;    double imag;};//下面定义成员函数Complex operator+(Complex &c1,Complex &c2){    Complex c;    c.real=c1.real+c2.real;    c.imag=c1.imag+c2.imag;    return c;}Complex operator-(Complex &c1,Complex &c2){    Complex c;    c.real=c1.real-c2.real;    c.imag=c1.imag-c2.imag;    return c;}Complex operator*(Complex &c1,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/(Complex &c1,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;}

感悟：对友元函数还是太陌生，不能与不用自如，看着书才写了出来.........