家谱（gen）——洛谷P2814

#include <iostream>  
#include <string> 
#include <map>
using namespace std;  
map < string, string > mp;  
int main()  
{   
    string s1 = "", s2 = "";  
    while(cin >> s1)  
    {  
        mp.clear();  
        while(s1 != "$")  
        {  
            if(s1[0] == '#')  
            {  
                s2 = s1.substr(1,s1.size()-1);  
                if(mp[s2] == "") mp[s2] = s2;  
            }  
            if(s1[0] == '+')  
            {  
                s1 = s1.substr(1,s1.size()-1);  
                while(mp[s2] != s2) s2 = mp[s2];  
                mp[s1] = s2;  
            }  
            if(s1[0] == '?')  
            {  
                s1 = s1.substr(1,s1.size()-1);  
                string s3 = s1;  
                while(s3 != mp[s3]) s3 = mp[s3];  
                cout << s1 << ' ' << s3 << endl;  
            }  
            cin >> s1;  
        }  
    }  
    return 0;  
}

充斥着STL的代码，感觉自己STL依赖症到了一个新的境界。。。

是个并查集（然而并没有看出来），用map控制映射。→_→