运算符的重载和模板3.4

4.  用运算符重载设计复数类，实现复数的+、-、*、/和<<运算

#include<iostream>
using namespace std;


class Complex
{
private:
    double o;//a是实部，b是虚部
    double p;
public:
    Complex(){};
    ~Complex(){};
    Complex(double a_,double b_):o(a_),p(b_){}
    friend Complex operator +(Complex &a,Complex &b);
    friend Complex operator -(Complex &a,Complex &b);
    friend Complex operator *(Complex &a,Complex &b);
    friend Complex operator /(Complex &a,Complex &b);
    Complex gonge();//共轭复数
    void display(Complex &a);
};

Complex operator +(Complex &a,Complex &b)
{
    double A,B;
    A=a.o+b.o;
    B=a.p+b.p;
    return Complex(A,B);
}

Complex operator -(Complex &a,Complex &b)
{
    double A,B;
    A=a.o-b.o;
    B=a.p-b.p;
    return Complex(A,B);
}

Complex operator *(Complex &a,Complex &b)
{
    double A;
    double B;
    A = a.o*b.o - a.p*b.p;
    B = a.p*b.o + a.o*b.p;
    return Complex(A,B);
}

Complex operator /(Complex &a, Complex &b)
{
    double fenmu;
    Complex A;
    Complex B;
    B = b.gonge();
    A = a*B;
    fenmu = b.o*b.o + b.p*b.p;
    return Complex(A.o / fenmu, A.p / fenmu);
}

void Complex::display(Complex &a)
{
    cout << a.o << "+";
    cout << a.p << "i" << endl;
}

Complex Complex::gonge()
{
    return Complex(this->o,-(this->p));
}



int main()
{
    Complex h(2,1),q(1,2),c;
    c =  h + q;
    c.display(c);
    c = h - q;
    c.display(c);
    c =  h * q;
    c.display(c);
    c =  h / q;
    c.display(c);
}