#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <complex>
using namespace std;

#define chmax(x, y) x = max(x, y)
#define chmin(x, y) x = min(x, y)

typedef long long ll;
typedef uint64_t ull;
typedef pair<int, int> P;
typedef pair<int, double> Pid;
typedef pair<double, int> Pdi;
typedef pair<ll, int> Pl;
typedef pair<ll, ll> Pll;
typedef pair<int, pair<int, int>> PP;
typedef pair<P, int> PPi;
constexpr double PI = 3.1415926535897932;   // acos(-1)
constexpr double EPS = 1e-9;
constexpr int INF = 1001001001;
constexpr int mod = 1e+9 + 7;
// constexpr int mod = 998244353;

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

    int n;
    cin >> n;
    vector<queue<int>> a(n);
    for(int i = 0; i < n; ++i){
        int p;
        cin >> p;
        for(int j = 0; j < p; ++j){
            int foo;
            cin >> foo;
            a[i].push(foo);
        }
    }
    bool update = true;
    while(update){
        update = false;
        for(int i = 0; i < n; ++i){
            if(a[i].empty())    continue;
            update = true;
            cout << a[i].front() << " ";
            a[i].pop();
        }
    }
    cout << endl;
}