// 以下程序是定义一个计数器类counter，对其重载运算符“+”。请编写运算符重载函数，使得程序输出结果如下：
//  n = 5
//  n = 10
//  n = 15

#include <iostream>
using namespace std;
class counter {
private:
    int n;

public:
    counter() {
        n = 0;
    }
    counter(int i) {
        n = i;
    }

    //_____________________
    //    {_____________________}

    counter operator+(const counter &otherCounter) {
        return counter(this->n + otherCounter.n);
    }

    void disp() {
        cout << "n=" << n << endl;
    }
};

int main() {
    counter c1(5), c2(10), c3;
    c3 = c1 + c2;
    c1.disp();
    c2.disp();
    c3.disp();
    return 0;
}