#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;

    vector<vector<int>> a(n);
    int k = 0;
    for (int i = 0; i < n; i++) {
        int p;
        cin >> p;

        a[i] = vector<int>(p);
        k += p;
        for (int j = 0; j < p; j++) {
            cin >> a[i][j];
        }
        reverse(a[i].begin(), a[i].end());
    }

    while (k) {
        for (int i = 0; i < n; i++) {
            if (!a[i].empty()) {
                cout << a[i].back() << " \n"[--k == 0];
                a[i].pop_back();
            }
        }
    }

    return 0;
}