#include "bits/stdc++.h"
using namespace std;
using ll     = long long;
using pii    = pair<int, int>;
using pll    = pair<ll, ll>;
using vi     = vector<int>;
using vl     = vector<ll>;
using vvi    = vector<vi>;
using vvl    = vector<vl>;
const ll INF = 1LL << 60;
const ll MOD = 1000000007;
template <class T>
bool chmax(T &a, const T &b) {
    return (a < b) ? (a = b, 1) : 0;
}
template <class T>
bool chmin(T &a, const T &b) {
    return (b < a) ? (a = b, 1) : 0;
}
template <class C>
void print(const C &c, std::ostream &os = std::cout) {
    std::copy(std::begin(c), std::end(c), std::ostream_iterator<typename C::value_type>(os, " "));
    os << std::endl;
}

int main() {
    int n;
    cin >> n;
    vector<deque<ll>> a(n);
    vl p(n);
    size_t tot = 0;
    for (int i = 0; i < n; ++i) {
        cin >> p[i];
        tot += p[i];
        a[i].resize(p[i]);
        for (int j = 0; j < p[i]; ++j) {
            cin >> a[i][j];
        }
    }
    vl ret;
    while (ret.size() != tot) {
        for (int i = 0; i < n; ++i) {
            if (a[i].size() != 0) {
                ret.push_back(a[i].front());
                a[i].pop_front();
            }
        }
    }
    print(ret);
    return 0;
}