用类的友元函数完成运算符的重载

/* * 程序的版权和版本声明部分 * Copyright (c)2012, 烟台大学计算机学院学生 * All rightsreserved. * 文件名称： object.cpp * 作者：刘清远* 完成日期： 2013年 4 月 22 日 * 版本号： v1.0 * 输入描述：无 * 问题描述： * 程序输出： */  #include <iostream>using namespace std;class Complex{public:Complex(){real=0;imag=0;}Complex(double r,double i){real=r;imag=i;}Complex operator+(Complex &c2);Complex operator-(Complex &c2);Complex operator*(Complex &c2);Complex operator/(Complex &c2);void display();private:double real;double imag;};Complex Complex::operator +(Complex&c2) { return Complex(real+c2.real,imag+c2.imag);}Complex Complex::operator-(Complex&c2){ return Complex(real-c2.real,imag-c2.imag);}Complex Complex::operator *(Complex&c2){ return Complex(real*c2.real+imag*c2.imag,real*c2.imag+imag*c2.real);}Complex Complex::operator /(Complex&c2){ return Complex((real*c2.real+imag*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag),(imag*c2.real-real*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag));  }void Complex::display(){cout<<"("<<real<<","<<imag<<"i)"<<endl;}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(); system ("pause"); return 0;}