class Solution {
public:
    string parent(string node,unordered_map<string,pair<string,int>> &um){
        while(node!=um[node].first){
            node=um[node].first;
        }
        return node;
    }
    vector<vector<string>> accountsMerge(vector<vector<string>>& accounts) {
        int n = accounts.size();
        unordered_map<string,pair<string,int>> um;
        unordered_map<string,int> vis;
        vector<priority_queue<string,vector<string>,greater<string>>> vpq(n);
        for(int **0;i<n;i++){
            for(int j=1;j<accounts[i].size();j++){
                um[accounts[i][j]].first = accounts[i][j];
                um[accounts[i][j]].second = i;
            }
        }
        for(int **0;i<n;i++){
            for(int j=2;j<accounts[i].size();j++){
                string a = parent(accounts[i][j],um);
                string b= parent(accounts[i][j-1],um);
                if(a==b) continue;
                um[a].first = b;
                um[b].second=i;
            }
        }
        for(int **0;i<n;i++){
            for(int j=1;j<accounts[i].size();j++){
                if(vis[accounts[i][j]]==1) continue;
                vis[accounts[i][j]]=1;
                string a = parent(accounts[i][j],um);
                int x = um[a].second;
                vpq[x].push(accounts[i][j]);
            }
        }
        //cout<<vpq[0].top();
        vector<vector<string>> ans;
        int x = -1;
        for(int **0;i<n;i++){
            int s = vpq[i].size();
            int flag=1;
            for(int j=0;j<s;j++){
                if(flag) {
                    x++;
                    ans.push_back(vector<string>());
                    ans[x].push_back(accounts[i][0]);
                    flag=0;
                }
                ans[x].push_back(vpq[i].top());
                vpq[i].pop();
            }
        }
        return ans;
    }
};