#include <bits/stdc++.h>
using namespace std;

int main(void) {
  int N, sum = 0;
  cin >> N;
  vector<queue<int>> v(N);
  for (int i = 0; i < N; i++) {
    int P;
    cin >> P;
    sum += P;
    for (int j = 0; j < P; j++) {
      int A;
      cin >> A;
      v[i].push(A);
    }
  }

  vector<int> ans;
  int emp_num = 0;
  while (emp_num < N) {
    emp_num = 0;
    for (int i = 0; i < N; i++) {
      if (!v[i].empty()) {
        ans.push_back(v[i].front());
        v[i].pop();
      } else {
        emp_num++;
      }
    }
  }

  for (int i = 0; i < sum - 1; i++) {
    cout << ans[i] << " ";
  }
  cout << ans[sum - 1] << endl;
  return 0;
}