<< 链式重载

#include <iostream>

using namespace std;

class Complex
{
private:
    int a, b;
public:
    Complex(int a, int b) :a(a), b(b)
    {}
    friend ostream& operator<<(ostream &out, Complex &c);

    void operator+(Complex &c)          //放在类里
    {
          this->a = this->a + c.a;
          this->b = this->b + c.b;
          //return *this;
    }

};

ostream& operator<<(ostream &out, Complex &c)
{
    out << "a = " << c.a << "  b = " << c.b;
    return out;
}

int main()
{
    Complex c1(1, 2), c2(3, 4);

    cout << c1 << "showmethemoney" << "aaaaa" << c1 << endl;
    //输出c1之后,返回cout(重载函数中手工返回),接着输出两个字符串(系统本身功能),再次返回cout(系统函数所定义的返回),最后又输出c1(重载函数功能),返回cout,最后endl;
    system("pause");
    return 0;
}