面向对象程序设计实验10

实验目的

• 掌握用成员函数重载运算符的方法;
• 掌握用友元函数重载运算符的方法.

实验要求

• 定义一个复数类,描述一些必须的成员函数,如:构造函数,析构函数,赋值函数,返回数据成员值的函数等;
• 定义运算符重载函数,通过重载运算符:+,-,*,/,直接实现二个复数之间的加减乘除运算.编写一个完整的程序,测试重载运算符的正确性.要求加法和乘法"+","*"用友元函数实现重载,减法和除法"-"，"/"用成员函数实现重载,参数是复数或实数;
• 通过重载运算符：>>,<<,=,直接实现复数的输入、输出及赋值运算,通过重载运算符:==,!=直接实现复数的比较运算,编写一个完整的程序,测试重载运算符的正确性.

操作菜单可参考如下格式:

1. 输入复数
2. 查看输入的复数
3. 复数相加
4. 复数相减
5. 复数相乘
6. 复数相除
7. 输出结果
0. 退出

代码

#include<iostream>
#include<algorithm>
#include<cstring>

using namespace std;

class Complex{
    public:
        Complex(double r=0,double i=0)
        {
            real=r;
            image=i;
        }
        ~Complex()
        {

        }
        double get_real();
        double get_image();

        friend Complex operator+(Complex &C1,Complex &C2);//友元+
        friend Complex operator*(Complex &C1,Complex &C2);//友元*
        Complex operator-(Complex &C1);//成员函数-
        Complex operator/(Complex &C1);//成员函数/
        friend istream& operator>>(istream&in,Complex&c);//输入
        friend ostream& operator<<(ostream&out,Complex&c);//输出
        Complex operator=(const Complex &C1);//赋值
        friend int operator==(Complex &C1,Complex &C2);//相等
        friend int operator!=(Complex &C1,Complex &C2);//不等
        void display();
    private:
        double real;
        double image;
};

double Complex::get_real()
{
    return real;
}

double Complex::get_image()
{
    return image;
}

Complex operator+(Complex &C1,Complex &C2)
{
    return Complex(C1.real+C2.real,C1.image+C2.image);
}

Complex operator*(Complex &C1,Complex &C2)
{
    //(a+bi)(c+di)=ac+(bc+ad)i+bdi^2=(ac-bd)+(bc+ad)i
    return Complex(C1.real*C2.real-C1.image*C2.image,C1.real*C2.image+C1.image*C2.real);
}

Complex Complex::operator-(Complex &C1)
{
    return Complex(get_real()-C1.get_real(),get_image()-C1.get_image());
}

Complex Complex::operator/(Complex &C1)
{
    /*Markdown语法
    $\frac{a+bi}{c+di}=\frac{(a+bi)(c-di)}{(c+di)(c-di)}$
    $=\frac{ac-adi+bci-bdi^2}{c^2-d^2\times i^2}$
    $=\frac{(ac+bd)+(bc-ad)i}{c^2+d^2}$
    */
    if(C1.get_real()==0&&C1.get_image()==0)
    {
        cout << "操作失败,分母不为0" << endl;
        exit(0);
    }
    else
    {
        double r=get_real()*C1.get_real()+get_image()*C1.get_image();
        double i=get_image()*C1.get_real()-get_real()*C1.get_image();
        double fenmu=C1.get_real()*C1.get_real()+C1.get_image()*C1.get_image();
        return Complex(r/fenmu,i/fenmu);   
    }
}

istream& operator>>(istream&in,Complex&c)
{
    cout << "请分别输入复数的实部和虚部(中间用空格隔开):  ";
    in >> c.real  >> c.image ;
    return in;
}

ostream& operator<<(ostream&out,Complex&c)
{
    out << c.real << '+' << c.image << 'i' << endl;
    return out;
}

Complex Complex::operator=(const Complex &C1)
{
    this->real=C1.real;
    this->image=C1.image;
    return *this;
}

int operator==(Complex &C1,Complex &C2)
{
    if(C1.real==C2.real&&C1.image==C2.image)
        return 1;
    else return 0;
}

int operator!=(Complex &C1,Complex &C2)
{
    if(C1.real!=C2.real||C1.image!=C2.image)
        return 1;
    else return 0;
}

void Complex::display()
{
    cout << get_real() << '+' << get_image() << 'i' << endl;
}

int displaymenu()
{
    int op;
    cout << "-------------功能菜单-------------" << endl;
    cout << "         1.输入复数"  << endl;
    cout << "         2.查看输入的复数"  << endl;
    cout << "         3.复数相加"  << endl;
    cout << "         4.复数相减"  << endl;
    cout << "         5.复数相乘"  << endl;
    cout << "         6.复数相除"  << endl;
    cout << "         7.复数判断相等" << endl;
    cout << "         8.复数判断相等" << endl;    
    cout << "         9.输出结果"  << endl;    
    cout << "         0.退出系统"  << endl;
    cout << "----------------------------------" << endl;
    cout << "请输入你要选择的功能编号(0-9):  ";
    while(cin >> op)
    {
        if(op>=0&&op<=9)
            break;
        else
            cout << "输入出错,请重新输入你要选择的功能编号(0,9):  ";
    }
    return op;
}

int main()
{
    Complex C,res,temp1,temp2;
    while(1)
    {
        int op=displaymenu();
        if(op==1)
            cin >> C;
        else if(op==2)
            cout << C ;
        else if(op==3)
        {
            cin >> temp1 >> temp2;
            res=temp1+temp2;
        }
        else if(op==4)
        {
            cin >> temp1 >> temp2;
            res=temp1-temp2;
        }
        else if(op==5)
        {
            cin >> temp1 >> temp2;
            res=temp1*temp2;
        }
        else if(op==6)
        {
            cin >> temp1 >> temp2;
            res=temp1/temp2;
        }
        else if(op==7)
        {
            cin >> temp1 >> temp2;
            if(temp1==temp2)
                cout << "两复数相等" << endl;
            else cout << "两复数不等" << endl;
        }
        else if(op==8)
        {
            cin >> temp1 >> temp2;
            if(temp1!=temp2)
                cout << "两复数不等" << endl;
            else cout << "两复数相等" << endl;            
        }
        else if(op==9)
        {
            cout << "结果为:  " ;
            res.display();
        }
        else if(op==0)
            break;
    }
    return 0;
}