运算符重载的三种方法

 

#include<iostream.h>
class Complex{
	public:
		Complex(int a,int b):x(a),y(b){}
		friend const Complex operator+(Complex &c1,Complex &c2);
	//	friend const Complex operator-(Complex &c1,Complex &c2);  //operator-不是友元函数
		const Complex operator*(Complex &c1); //是成员函数的时候
		friend const Complex operator/(Complex &c1,Complex &c2);

	public:
		void show();
		int getX();
		int getY();
	private:
		int x;
		int y;
};
inline const Complex operator+(Complex &c1,Complex &c2)
{
	return Complex(c1.x+c2.x,c1.y+c2.y);
}
inline const Complex operator-(Complex &c1,Complex &c2)
{
	return Complex(c1.getX()-c2.getX(),c1.getY()-c2.getY());
}
const Complex Complex::operator*(Complex &c1)
{
	return Complex(this->x*c1.getX(),this->y*c1.getY());
}
inline const Complex operator/(Complex &c1,Complex &c2)
{
	if(c2.x==0||c2.y==0)
		return Complex(0,0);
	return Complex(c1.x/c2.x,c1.y/c2.y);
}

void Complex::show()
{
	cout<<"x:"<<x<<endl;
	cout<<"y:"<<y<<endl;
}
int Complex::getX()
{
	return x;
}
int Complex::getY()
{
	return y;
}
int main()
{

	Complex c1(1,1);  
	Complex c2(1,1);
	Complex c3=c1+c2;//相当于调用函数 operator+(c1,c2)
	c3.show();

	Complex c4=c1-c2;
	c4.show();

	Complex c5=c1*c2;//相当于调用函数 x.operator*(c1)
	c5.show();
	return 0;
}