操作符的重载

cout << "hello" << endl << "world";
输出：
hello world

	int x;
	cout << "input the num what you want:";
	cin >> x;
	cout << "the num  you input is:";
	cout << x;

struct Complex
{
	int a;
	int b;
};
// 操作符的重载
Complex operator+ (Complex &c1, Complex &c2)
{
	Complex k;
	k.a = c1.a + c2.a;
	k.b = c1.b + c2.b;
	return k;
}
int main()
{
	Complex a1 = { 1, 2 };
	Complex a2 = { 3, 4 };
	Complex a3 = operator+(a1, a2);
// 也可以直接：Complex a3 = a1 + a2;
	cout << "a3.a=" << a3.a << endl;
	cout << "a3.b=" << a3.b << endl;
	while (1);
}

class Complex
{
	int a;  // 默认的是私有的
	int b;
public:
	Complex(int a = 0, int b = 0) 
	{
		this->a = a;
		this->b = b;
	}
	int getA()
	{
		return a;
	}
	int getB()
	{
		return b;
	}
	~Complex()
	{
	}
	// 指定朋友，友元函数
	friend Complex operator+ (Complex &c1, Complex &c2);
};
// 操作符的重载
Complex operator+ (Complex &c1, Complex &c2)
{
	Complex k;
	// 这样可以通过对象访问到private成员
	//k.a = c1.getA() + c2.getA();
	//k.b = c1.getB() + c2.getB();
	k.a = c1.a + c2.a; // 通过对象直接访问
	k.b = c1.b + c2.b;
	return k;
}
int main()
{
	Complex a1(1, 2);
	Complex a2(3, 4);
	Complex a3 = a1 + a2;
	cout << "a3.a = " << a3.getA() << endl;
	cout << "a3.b = " << a3.getB() << endl;
	while (1);
}

ostream& operator<< (ostream& out, Complex &c)
{ // 这个地方看不懂
	out << c.a << " and " << c.b << endl;
	return out;
}
int main()
{
	Complex a1(1, 2);
	Complex a2(3, 4);
	Complex a3 = a1 + a2;
	cout << a3 << endl;
	while (1);
}

class Complex
{
	int a;  // 默认的是私有的
	int b;
public:
	Complex(int a = 0, int b = 0) 
	{
		this->a = a;
		this->b = b;
	}
	int getA()
	{
		return a;
	}
	int getB()
	{
		return b;
	}
	~Complex()
	{
	}
	// 这里第一个对象有传入 this 指针，所以只需要一个就可以了，
	Complex operator+ (Complex &c2);
};
Complex Complex :: operator + (Complex &c2)
{
	Complex k;
	k.a = this->a + c2.a;
	k.b = this->b + c2.b;
	return k;
}
int main()
{
	Complex a1(1, 2);
	Complex a2(3, 4);
	Complex a3 = a1 + a2;
	cout << a3.getA() << endl;
	cout << a3.getB() << endl;
	while (1);
}