[c++]複數的運算符重載

類的定義和聲明：

<span style="font-size:32px;">#include<iostream>
#include<string>
using namespace std;

class Complex
{
    friend istream& operator>>(istream &in, Complex &c);//友元不屬於類，聲明在哪都無所謂
    friend ostream& operator<<(ostream &out, const Complex &c);
    friend Complex operator+(int x, Complex &c);//當左操作數不爲對象時就用友元定義
public:
    Complex(const int real=0,const int imag=0):m_real(real),m_imag(imag)
    {}
    ~Complex()
    {}
    void Show()const
    {
        cout<<"("<<m_real<<","<<m_imag<<")"<<endl;
    }

public:
    Complex operator+(Complex &c)
    {
        return Complex(m_real+c.m_real,m_imag+c.m_imag);
    }

    Complex operator-(Complex &c)
    {
        return Complex(m_real-c.m_real,m_imag-c.m_imag);
    }


    Complex operator*(Complex &c);
    Complex operator/(Complex &c);
    Complex operator+=(Complex &c);
    Complex operator-=(Complex &c);
    Complex operator*=(Complex &c);
    Complex operator/=(Complex &c);
    Complex operator+(int x);
    //friend Complex operator+(int x, Complex &c);
private:
    int m_real;
    int m_imag;
};


Complex Complex::operator+(int x)
{
    return Complex(m_real+x,m_imag);
}

Complex Complex:: operator+=(Complex &c)
{
    m_real = m_real+c.m_real;
    m_imag = m_imag+c.m_imag;
    return *this;
}

Complex Complex::operator-=(Complex &c)
{
    m_real = m_real - c.m_real;
    m_imag = m_imag - c.m_imag;
    return *this;
}


Complex Complex:: operator*(Complex &c)
{
    return Complex(m_real*c.m_real-m_imag*c.m_imag,m_imag*c.m_real+m_real*c.m_imag);
}

Complex Complex::operator*=(Complex &c)
{
    int i = m_real;
    m_real = m_real*c.m_real-m_imag*c.m_imag;
    m_imag = m_imag*c.m_real+i*c.m_imag;
    return *this;
}

Complex Complex::operator/(Complex &c)
{
    Complex temp;

    temp.m_real = (m_real*c.m_real+m_imag*c.m_imag)/(c.m_real*c.m_real+c.m_imag*c.m_imag);
    temp.m_imag = (m_imag*c.m_real-m_real*c.m_imag)/(c.m_real*c.m_real+c.m_imag*c.m_imag);
    return temp;
}

Complex Complex:: operator/=(Complex &c)
{
    int i = m_real;
    m_real = (m_real*c.m_real+m_imag*c.m_imag)/(c.m_real*c.m_real+c.m_imag*c.m_imag);
    m_imag = (m_imag*c.m_real-i*c.m_imag)/(c.m_real*c.m_real+c.m_imag*c.m_imag);
    return *this;
}
ostream& operator<<(ostream &out, const Complex &c)
{
    out<<"("<<c.m_real<<","<<c.m_imag<<")";
    return out;
}

istream& operator>>(istream &in, Complex &c)
{
    in>>c.m_real>>c.m_imag;
    return in;
}
</span>

測試程序：

<span style="font-size:32px;">int main()
{
    Complex c1(1,1);
    Complex c2(1,-1);
    
    Complex c;
    //c1.operator+(c2)
    c = c1 + c2;
    cout<<c<<endl;
//    c = c1 * c2;
//    cout<<c<<endl;
//    c = c1 / c2;
//    cout<<c<<endl;
//    c = 2 + c1;
//    cout<<c<<endl;
//    c1+=c2;
//    cout<<c1<<endl;
//    c1-=c2;
//    cout<<c1<<endl;
//    c1*=c2;
//    cout<<c1<<endl;
//    c1/=c2;
//    cout<<c1<<endl;
//請不要把它們一起測試，分開
    Complex c3;
    cin>>c3;
    cout<<c3;
    return 0;
}</span>