第九周任务一 复数 输入输出运算符的重载

/* (程序头部注释开始)
* 程序的版权和版本声明部分
* Copyright (c) 2011, 烟台大学计算机学院学生 
* All rights reserved.
* 文件名称： 
* 作    者：  姜雅明  
* 完成日期：  2012    年   04    月   17    日
* 版 本 号：  1.0

* 对任务及求解方法的描述部分
* 输入描述： 输入一个复数
* 问题描述： 复数的四则运算
* 程序输出： 运算后的值
* 程序头部的注释结束
*/

#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);
	friend ostream & operator << (ostream &output, Complex &c);
	friend istream & operator >> (istream &iutput, Complex &c);
private:
	double real;
	double imag;
};
//下面定义成员函数
Complex operator + (Complex &c1, Complex &c2)
{
	return Complex (c1.real + c2.real, c1.imag + c2.imag);
}

Complex operator - (Complex &c1, Complex &c2)
{
	return Complex (c1.real - c2.real, c1.imag - c2.imag);
}

Complex operator * (Complex &c1, Complex &c2)
{
	return Complex (c1.real * c2.real - c1.imag * c2.imag, c1.imag * c2.real + c1.real * c2.imag);
}

Complex operator / (Complex &c1, Complex &c2)
{
	return Complex ((c1.real * c2.real + c1.imag * c2.imag) / (c2.imag * c2.imag + c2.real * c2.real),
		(c1.imag * c2.real - c1.real * c2.imag) / (c2.imag * c2.imag + c2.real * c2.real));
}

ostream & operator << (ostream &output, Complex &c)
{
	output << "(" << c.real;

	if(c.imag > 0) output << "+";

	output << c.imag << "i)";

	return output;
}
istream & operator >> (istream &input, Complex &c)
{
	int a, b;

	char sign, i;

	do
	{
		cout << "请输入一个复数(a+bi)或(a-bi):";
		input >> a >> sign >> b >> i;
	}
	while((sign != '+' || sign != '-') && i != 'i');

	c.real = a;

	c.imag = (sign == '+') ? b : -b;

	return input;
}

int main()
{
	Complex c1,c2,c3;

	cin >> c1;

	cin >> c2;

	c3 = c1 + c2;

	cout << "c1+c2=";

	cout << c3 << endl;

	c3 = c1 - c2;

	cout << "c1-c2=";

	cout << c3 << endl;

	c3 = c1 * c2;

	cout << "c1*c2=";

	cout << c3 << endl;

	c3 = c1 / c2;

	cout << "c1/c2=";

	cout << c3 << endl;

	system("pause");
	return 0;
}