加号運算符重載

1.運算符重載：對已有的運算符重新進行定義，賦予其另一種功能，以适應不同的資料類型

2.加号運算符重載：實作兩個自定義資料類型相加的運算

#include<iostream>
using namespace std;
#include<string>

//加号運算符重載

class Person
{
public:
	//1.成員函數重載+号
	/*Person operator+(Person &p)
	{
		Person temp;
		temp.m_a = this->m_a + p.m_a;
		temp.m_b = this->m_b + p.m_b;
		return temp;
	}*/
	int m_a;
	int m_b;
};

//2.全局函數重載+号
Person operator+(Person &p1,Person &p2)
{
	Person temp;
	temp.m_a = p1.m_a + p2.m_a;
	temp.m_b = p1.m_b + p2.m_b;
	return temp;
}

//函數重載版本
Person operator+(Person &p1, int num)  //與全局函數重載+号相比，參數類型不同
{
	Person temp;
	temp.m_a = p1.m_a + num;
	temp.m_b = p1.m_b + num;
	return temp;
}
void test1()
{
	Person p1;
	p1.m_a = 1;
	p1.m_b = 2;

	Person p2;
	p2.m_a = 3;
	p2.m_b = 4;
	//成員函數重載本質調用 Person p3 = p1.operator+(p2);
	//全局函數重載本質調用 Person p3 = p1.operator+(p1，p2);
	Person p3 = p1 + p2;
	cout << "p3.m_a=" << p3.m_a << endl; //4
	cout << "p3.m_b=" << p3.m_b << endl;  //6

	//運算符重載也可以發生函數重載
	Person p4 = p1 + 10;
	cout << "p4.m_a=" << p4.m_a << endl; //  11
	cout << "p4.m_b=" << p4.m_b << endl;//  12
}


int main()
{
	test1();
	system("pause");
	return 0;
}