#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

typedef long long ll;

int main () {
    int n;
    cin >> n;
    vector<int> p(n);
    vector< vector<int> > a(n , vector<int>());
    for (int i = 0; i < n; i++) {
        cin >> p[i];
        int now;
        for (int j = 0; j < p[i]; j++) {
            cin >> now;
            a[i].push_back(now);
        }
    }
    sort(p.begin() , p.end());
    int p_mx = p.back();
    for (int i = 0; i < p_mx; i++) {
        for (int j = 0; j < n; j++) {
            if (a[j].size() > 0) {
                cout << a[j][0] << " ";
                a[j].erase(a[j].begin());
            }
        }

    }
    cout << endl;
    return 0;
}