期末之九运算符重载

将加减运算符重载为复数类成员函数
规则：实部虚部分别相加减。操作数：两个操作数都是复数类的对象
#include<iostream>
using namespace std;
class complex {
public:
    complex(double r = 0.0, double i = 0.0) :real(r),image(i)
    {}
    complex operator + (const complex& rc2) const;
    complex operator - (const complex& rc2) const;
    void display();
    double real, image;
};
complex complex::operator + (const complex& rc2) const 
{
    return complex(real + rc2.real, image + rc2.image);
}
complex complex::operator - (const complex& rc2) const
{
    return complex(real - rc2.real, image - rc2.image);
}
void complex::display()
{
    cout << "(" << real << "," << image << ")" << endl;
}
int main()
{
    complex c1(2, 4), c2(1, 3), c3,c4;
    cout <<"c1=" <<"(" << c1.real << "," << c1.image << ")" << endl;
    cout << "c2=" << "(" << c2.real << "," << c2.image << ")" << endl;
    c3 = c1 + c2;
    c4 = c1 - c2;
    cout << "c3 = c1 + c2";
    c3.display();
    cout << "c4 = c1 - c2";
    c4.display();
}