C++重载流插入和流输出运算符

demo:

/*
	Name: 重载输入输出流运算符使力代码 
	Copyright: qianshou 
	Author: zhaozhe
	Date: 07/12/13 00:11
	Description: 
				首先定义一个复数类，然后重载输入，输出运算符
				以及+运算符，以实现复数的输出，相加和输出操作 
*/

#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 ostream & operator << (ostream &output,Complex &c);
		friend istream & operator >> (istream &input ,Complex &c);
	private:
		double real;
		double imag;
};
Complex operator+(Complex &c1,Complex &c2)
{
	return Complex(c1.real+c2.real,c1.imag+c2.imag);
}
ostream & operator << (ostream &output,Complex &c)
{
	output<<"("<<c.real<<","<<c.imag<<")"<<endl;
	return output;
}
istream & operator >> (istream &input ,Complex &c)
{
	input>>c.real>>c.imag;
	return input;
}
int main()
{
	Complex c1,c2,c3;
	cout<<"please input c1:";
	cin>>c1;
	cout<<"please input c2:";
	cin>>c2;
	c3=c1+c2;
	cout<<"c3=c1+c2"<<endl;
	cout<<"c1:"<<c1;
	cout<<"c2:"<<c2;
	cout<<"c3=c1+c2"<<endl;
	cout<<"c3:"<<c3;
	return 0;
}

print:

/*
	please input c1:3 5
	please input c2:2 -1
	c3=c1+c2
	c1:(3,5)
	c2:(2,-1)
	c3=c1+c2
	c3:(5,4)
*/