SDUSTOJ Problem 1818: 一切皆对象

Description

一切都是对象 —— Everything is an object。
所以，现在定义一个类Thing，来描述世界上所有有名字的事物。该类只有构造函数、拷贝构造函数和析构函数，并具有一个字符串数据成员来存储其名字。

Input

输入只有1行，是一个没有空白符的字符串。

Output

见样例。

Sample Input

NAME

Sample Output

A thing without name is created!
A thing without name is copied!
A thing named by NAME is created!
A thing named by NAME is copied!
A thing named by NAME is erased!
A thing named by NAME is erased!
A thing without name is erased! A thing without name is erased!

HINT

Append Code

append.cc

标程

#include <bits/stdc++.h>
using namespace std;
 
class Thing {
    public:
        Thing() {cout << "A thing without name is created!\n";}
        Thing(string s):n(s) {cout << "A thing named by " << n << " is created!\n";}
        Thing(const Thing& t):n(t.n) {
            if(n.length()) cout << "A thing named by " << n <<" is copied!\n";
            else cout << "A thing without name is copied!\n";
        }
        ~Thing() {
            if(n.length()) cout << "A thing named by "<< n <<" is erased!\n";
            else cout << "A thing without name is erased!\n";
        }
 
    private:
        string n;
};
 
int main()
{
    string name;
    Thing Thing1, Thing2(Thing1);
    cin>>name;
    Thing Thing3(name);
    Thing Thing4(Thing3);
    return 0;
}