第八周项目零（2）：阅读程序：运算符重载

#include <iostream>
using namespace std;
class Sample
{
private:
    int x;
public:
    Sample() {}
    Sample (int a)
    {
        x=a;
    }
    void disp()
    {
        cout<<"x="<<x<<endl;
    }
    Sample operator+(Sample &s);
};
Sample Sample:: operator+( Sample &s)
{
    return Sample(x+s.x);
}
int main()
{
    Sample obj1(20);
    Sample obj2(20);
    Sample obj3;
    obj3=obj1+obj2;
    obj3.disp();
    return 0;
}