复现complex类（持续更新）

2021/1/13 

 

#ifndef __MYCOMPLEX__
#define __MYCOMPLEX__

class mycomplex;
mycomplex&
__doapl(mycomplex* ths, const mycomplex& r);

class mycomplex 
{
public:
    mycomplex (double r = 0 , double i = 0)
        :re(r),im(i){}
    mycomplex& operator += (const mycomplex&);
    double real() const { return re; }
    double imag() const { return im; }

private:
    double re, im;
    
    friend mycomplex& __doapl(mycomplex*, const mycomplex&);
};

inline mycomplex&
__doapl(mycomplex * ths, const mycomplex& r)
{
    ths->re += r.re; 
    ths->im += r.im;
    return *ths;
}

inline mycomplex&
mycomplex::operator += (const mycomplex& r) 
{
    return __doapl(this, r);
}

inline double
imag(const mycomplex& x)
{
    return x.imag();
}

inline double
real(const mycomplex& x)
{
    return x.real();
}

// 为什么 重载+ 不设为成员函数，因为不仅仅要考虑到 complex对象 + complex对象，也要考虑到 实数 + complex对象 和 complex对象 + 实数。
inline mycomplex
operator + (const mycomplex& x, const mycomplex& y) 
{
    return mycomplex(real(x) + real(y), 
                     imag(x) + imag(y));
}

inline mycomplex
operator + (double x, const mycomplex& y)
{
    return mycomplex(x+real(y),
                     imag(y));
}

inline mycomplex
operator + (const mycomplex& x, double y)
{
    return mycomplex(real(x) + y,
                     imag(x));
}


#endif