#include <bits/stdc++.h>

#define EPS (1e-7)
#define INF (1e9)
#define LINF (1e18)
#define PI (acos(-1))
#define MOD 1000000007
#define MAX 100000

using namespace std;
typedef long long ll;

int main()
{
  int N; cin >> N;

  vector<vector<int>> A(N);

  int m = 0;
  for (int i = 0; i < N; ++i) {
    int P; cin >> P;
    m = max(m, P);
    A[i].resize(P);
    for (int j = 0; j < P; ++j) cin >> A[i][j];
  }

  vector<int> ans;
  for (int i = 0; i < m; ++i) {
    for (int j = 0; j < N; ++j) {
      if (A[j].size() <= i) continue;
      ans.push_back(A[j][i]);
    }
  }

  for (int i = 0; i < ans.size(); ++i) {
    if (i) cout << " ";
    cout << ans[i];
  }
  cout << endl;
}