普通并查集，但是由于为字符串，所以用map存储关系

注意merge时并非将 本人的祖先与祖先合并!

#include <bits/stdc++.h>
#define int long long int

using namespace std;

const int N = 1e5 + 7;
map<string,string> bond;
string s1,s; 

string get(string x){
    if(bond[x] == x)return x;
    return bond[x] = get(bond[x]);
}

void merge(string x,string y){
    y = get(y);
    bond[x] = y;
}

signed main(){
    char ch = getchar();
    while(ch != '$'){
    if(ch == '#'){
        cin >> s;
        if(bond[s] == "")bond[s] = s;
    }
    if(ch == '+'){
        cin >> s1;
        merge(s1,s); 
    }
    if(ch == '?'){
        cin >> s;
        get(s);//更新祖先确保最早
        cout << s << " " << bond[s] << endl;
    }
        ch = getchar();
    }
    return 0;
}