18、运算符重载

一、单目运算符重载

#include <iostream>
using namespace std;

class CPoint
{
private:
    int x, y;
public:
    CPoint(int _x=0, int _y=0):x(_x),y(_y){}
    void display(){cout<<x<<" "<<y<<endl;}
    CPoint operator ++ (int);
};

CPoint CPoint::operator ++ (int)
{
    return CPoint(x++, y++);
}

int main(void)
{
    CPoint a,c(1,1);
    a=c++;
    a.display();
    c.display();
    return 0;
}

二、友元函数的重载

#include <iostream.h>

class complex
{
private:
    double x, y;

public:
    complex(double xx = 0, double yy = 0){x = xx; y = yy;}

    double getx(){return x;}
    double gety(){return y;}

    void display()
    {
        cout<<"x = "<<x<<endl;
        cout<<"y = "<<y<<endl;
    }
    friend complex operator * (complex &c1,complex &c2); //定义友元函数重载
};

complex operator * (complex &c1, complex &c2) //定义重载算术运算符

{
    complex c;
    c.x = c2.x * c1.x;
    c.y = c2.y * c1.y;
    return c;
}

void main()
{
    complex c1(3,4),c2(4,-5),c3;
    c3= c1*c2; //这个就是对运算符“*”的重载

    c1.display();

    c2.display();