第九周【项目1】在第8周项1的基础上（1）再定义一目运算符 -，-c相当于0-c（2）定义Complex类中的<<和>>运算符的重载，实现输入和输出，改造原程序中对运算结果显示方式，使程序读起来更自然

/*
* 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.
* 作者：    初瑞
* 完成日期： 2013年 4 月 26 日
* 版本号： v1.0
* 输入描述：无
* 问题描述：无
* 程序输出：无
*/

#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 &c);
Complex operator-(Complex &c);
Complex operator*(Complex &c);
Complex operator/(Complex &c);
friend Complex operator+(double &d,Complex &c);//实数加复数必须用友原函数
Complex operator+(double &d);//复数加实数一般函数
friend Complex operator-(double &d,Complex &c);//实数加复数
Complex operator-(double &d);//复数加实数
friend Complex operator*(double &d,Complex &c);//实数加复数
Complex operator*(double &d);//复数加实数
friend Complex operator/(double &d,Complex &c);//实数加复数
Complex operator/(double &d);//复数加实数
friend Complex operator-(Complex &c);//相反数相当于（0-c），即实数减复数，所以用友原函数
friend istream&operator>>(istream&,Complex&);
friend ostream&operator<<(ostream&,Complex&);
private:
double real;
double imag;
};

Complex Complex::operator+(Complex &c)
{
return Complex(real+c.real,imag+c.imag);
}

Complex Complex::operator-(Complex &c)
{
return Complex(real-c.real,imag-c.imag);
}

Complex Complex::operator*(Complex &c)
{
return Complex(real*c.real-imag*c.imag,real*c.imag+imag*c.real);
}

Complex Complex::operator/(Complex &c)
{
double d;
d=c.real*c.real+c.imag*c.imag;
return Complex((real*c.real+imag*c.imag)/d,(imag*c.real-real*c.imag)/d);
}

Complex operator+(double &d,Complex &c)//实数加复数，友原函数
{
return Complex(d+c.real,c.imag);
}

Complex Complex::operator+(double &d)//复数加实数，一般函数
{
return Complex(real+d,imag);
}

Complex operator-(double &d,Complex &c)//实数加复数，友原函数
{
return Complex(d-c.real,c.imag);
}

Complex Complex::operator-(double &d)//复数加实数，一般函数
{
return Complex(real-d,imag);
}

Complex operator*(double &d,Complex &c)//实数加复数，友原函数
{
return Complex(d*c.real,d*c.imag);
}

Complex Complex::operator*(double &d)//复数加实数，一般函数
{
return Complex(real*d,imag*d);
}

Complex operator/(double &d,Complex &c)//实数加复数，友原函数
{
return Complex(d/c.real,d/c.imag);
}

Complex Complex::operator/(double &d)//复数加实数，一般函数
{
return Complex(real/d,imag/d);
}

Complex operator-(Complex &c)//相反数，友原函数
{
return Complex(-c.real,-c.imag);
}

istream&operator>>(istream&input,Complex &c)//知道
{
cout<<"请输入复数的实部和虚部：";
input>>c.real>>c.imag;
return input;
}

ostream&operator<<(ostream &output,Complex &c)//知道
{
output<<"("<<c.real;
if(c.imag>=0)
output<<"+";
output<<c.imag<<"i)"<<endl;
return output;
}

int main()
{
double d=9;
Complex c1,c2,c3;
cin>>c1;
cout<<"c1=";
cout<<c1;

cin>>c2;
cout<<"c2=";
cout<<c2;

c3=c1+c2;
cout<<"c1+c2=";
cout<<c3;

c3=c1-c2;
cout<<"c1-c2=";
cout<<c3;

c3=c1*c2;
cout<<"c1*c2=";
cout<<c3;

c3=c1/c2;
cout<<"c1/c2=";
cout<<c3;

c3=d+c1;
cout<<"d+c1=";
cout<<c3;

c3=c1+d;
cout<<"c1+d=";
cout<<c3;

c3=d-c1;
cout<<"d-c1=";
cout<<c3;

c3=c1-d;
cout<<"c1-d=";
cout<<c3;

c3=d*c1;
cout<<"d*c1=";
cout<<c3;

c3=c1*d;
cout<<"c1*d=";
cout<<c3;

c3=d/c1;
cout<<"d/c1=";
cout<<c3;

c3=c1/d;
cout<<"c1/d=";
cout<<c3;

c3=-c1;
cout<<"-c1=";
cout<<c3;

return 0;
}