第八周项目一の任务三----扩展功能，使之能与double型数据进行运算

/*
* 程序的版权和版本声明部分
* Copyright (c)2013, 烟台大学计算机学院学生
* All rightsreserved.
* 文件名称： object.cpp
* 作者：赵晓晨
* 完成日期： 2013年04月18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;}
//重载函数做友元函数（与double型数据进行运算）
friend Complex operator+(double c1,Complex &c2);
friend Complex operator-(double c1,Complex &c2);
friend Complex operator*(double c1,Complex &c2);
friend Complex operator/(double c1,Complex &c2);
friend Complex operator-(Complex &c2);
void display();
private:
double real;
double imag;
};
//定义运算符+重载函数
Complex operator+(double c1,Complex &c2)
{
return Complex(c1+c2.real,c2.imag);
}
Complex  operator-(double c1,Complex &c2)
{
return Complex(c1-c2.real,c2.imag);
}
Complex  operator*(double c1,Complex &c2)
{
return Complex(c1*c2.real,c1*c2.imag);
}
Complex  operator/(double c1,Complex &c2)
{
double d=c2.imag*c2.imag+c2.real*c2.real;
return Complex(c1*c2.real/d,-c1*c2.imag/d);
}
Complex   operator-(Complex &c2)
{
return Complex(-c2.real,-c2.imag);
}
void Complex::display()
{
if(imag>0)
cout<<real<<"+"<<imag<<"i"<<endl;
else
cout<<real<<imag<<"i"<<endl;
}
//main函数进行测试
int main()
{
Complex c1(1,2),c2(-1,-2),c3(3,4),c4(-3,-4),c5,c6,c7,c8,c9(5,6),c10;
c5=1.2+c1;
c5.display();
c6=2.3-c2;
c6.display();
c7=2.1*c3;
c7.display();
c8=2.5/c4;
c8.display();
c10=-c9;
c10.display();
return 0;
}