#include <bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );
using namespace std;
using ll = long long;

int main(){
    int n;
    cin >> n;
    vector<queue<int>> v(n);

    rep(i, n){
        int m;
        cin >> m;
        rep(j, m){
            int t;
            cin >> t;
            v[i].push(t);
        }
    }

    vector<int> ans;
    bool flag = true;
    while(flag){
        flag = false;
        rep(i, n){
            if(v[i].size() == 0) continue;
            int t = v[i].front();
            v[i].pop();
            ans.push_back(t);
            flag = true;
        }
    }

    rep(i, ans.size()) cout << ans[i] << " ";
    cout << endl;
}