第八週實驗報告（任務1-方案2）

程序頭部註釋開始
* 程序的版權和版本聲明部分
* Copyright (c) 2011, 煙臺大學計算機學院學生
* All rights reserved.
* 文件名稱：     用友元函數完成運算符重載          
* 作    者：     郭廣建                       
* 完成日期：  2012年    04  月  10     日
* 版 本 號：  1.0

題目介紹：

方案二：請用類的友元函數，而不是成員函數，完成上面提及的運算符的重載；

源程序：

#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);
    void display();
private:
    double real;
    double imag;
};
//下面定義成員函數
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.real * c2.imag + c1.imag + c2.real));
}
Complex operator/(Complex &c1, Complex &c2)
{
	return Complex((c1.real * c2.real + c1.imag * c2.imag )/(c2.real * c2.real + c2.imag * c2.imag) ,( c1.imag + c2.real - c1.real * c2.imag)/(c2.real * c2.real + c2.imag * c2.imag));
}
void Complex::display()
{
	cout << '(' << real << ',' << imag << ')' <<endl;
} 
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();
    system("pause");
    return 0;
}

運行結果：