第八周 项目一（2）：实现复数类中的运算符重载（友元函数）

/*
* 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;
}