第八週實驗報告（一）

* (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：實現複述類中的運算符的重載
  
* 作 者：齊豔紅  
  
 * 完成日期： 2011年 4月 8日  
  
*版 本 號：  
  
 * 對任務及求解方法的描述部分：利用類的成員函數完成運算符的重載  
  
 *問題描述：定義一個複數類重載運算符，使之能用於複數的加減乘除 
    
 * 程序輸出：  
  
* 程序頭部的註釋結束*/  
方案一
利用類的成員函數完成運算符的重載

#include  
using namespace std;  
class Complex  
{  
public:  
    Complex(){real=0;imag=0;}  
    Complex(double r,double i){real=r;imag=i;}  
    Complex operator+(Complex &c2);  
    Complex operator-(Complex &c2);  
    Complex operator*(Complex &c2);  
    Complex operator/(Complex &c2);  
    void display();  
private:  
    double real;  
    double imag;  
};  
//下面定義成員函數  
Complex Complex::operator+(Complex &c2)  
{  
    return Complex((real+c2.real),(imag+c2.imag));  
}  
Complex Complex::operator-(Complex &c2)   
{   
    return Complex((real-c2.real),(imag-c2.imag));  
}  
Complex Complex::operator*(Complex &c2)  
{  
    return Complex((real*c2.real - imag*c2.imag),(real*c2.imag + imag*c2.real));  
}  
Complex Complex::operator/(Complex &c2)  
{  
    return Complex((real*c2.real + imag*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag),(-real*c2.imag + imag*c2.real)/(c2.real*c2.real+c2.imag*c2.imag));  
}  
void Complex::display()  
{  
    cout<<"("<<real<<","<<imag<<"i)"<<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;  
}  

 

 

方案二定義一個複數類（友元函數）重載運算符，使之能用於複數的加減乘除

#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.real*c2.imag + c1.imag*c2.real)/(c2.real*c2.real+c2.imag*c2.imag));  
}  
void Complex::display()  
{  
    cout<<"("<<real<<","<<imag<<"i)"<<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;  
}  

#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);//聲明重載函數加作爲友元函數   
    friend Complex operator-(Complex &c1,Complex &c2);//聲明重載函數減作爲友元函數   
    friend Complex operator*(Complex &c1,Complex &c2);//聲明重載函數加乘作爲友元函數   
    friend Complex operator/(Complex &c1,Complex &c2);//聲明重載函數除作爲友元函數   
    friend Complex operator+(Complex &c1, const double &d); //聲明重載函數第一個參數可以不是類對象   
    friend Complex operator+(const double &d,Complex &c1);//聲明重載函數第二個參數可以不是類對象   
    friend Complex operator-(Complex &c2);//聲明一目運算符形如"-c"   
    void display();  
private:  
    double real;  
    double imag;  
};  
//定義友元函數加法   
Complex operator+(Complex &c1,Complex &c2)  
{  
    return Complex(c1.real + c2.real,c1.imag + c2.imag);  
}  
//定義複數加double型的數   
Complex operator+(Complex &c1,const double &d)  
{  
    return Complex(c1.real + d,c1.imag);  
}  
Complex operator+(const double &d,Complex &c1)  
{  
    return Complex(c1.real + d,c1.imag);  
}  
//定義友元函數減法   
Complex operator-(Complex &c1,Complex &c2)  
{  
    return Complex(c1.real - c2.real,c1.imag - c2.imag);  
}  
//定義一目運算符形如"-c"   
Complex operator-(Complex &c2)    
{    
    return Complex(-c2.real, -c2.imag);    
}   
//定義友元函數乘法   
Complex operator*(Complex &c1,Complex &c2)  
{  
    Complex c;      
    c.real = c1.real*c2.real - c1.imag*c2.imag;      
    c.imag = c1.real*c2.imag + c1.imag*c2.real;      
    return c;  
}  
//定義友元函數除法   
Complex operator/(Complex &c1,Complex &c2)  
{      
    Complex c;      
    c.real = (c1.real*c2.real + c1.imag*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag);      
    c.imag = (-c1.real*c2.imag + c1.imag*c2.real)/(c2.real*c2.real+c2.imag*c2.imag);     
    return c;      
}   
void Complex::display()  
{      
    cout<<"("<<real<<","<<imag<<"i)"<<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();  
    c3=2.15+c1;  
    cout<<"2.15+c1=";  
    c3.display();  
    c3=c1+2.15;  
    cout<<"c1+2.15=";  
    c3.display();  
    c3=-c2;  
    cout<<"-c2=";  
    c3.display();  
    system("pause");  
    return 0;  
}

總結：運算符不同情況下，是不同的身份，好像在家裏我們是子女，在學校我們是學生一樣，所以，既要把子女的身份用好，也得把學生身份用好，也要清楚不同情況下各自是什麼身份······友元函數必須有兩個參數，但這個用V ·c++6.0有一個錯誤，2008打不開沒辦法做，所以，先提交了這個·······