#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
#else
  #define Debug(...) void(0)
#endif
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

int main() {
  int n;
  cin >> n;
  vector<queue<int>> a(n);
  rep(i, n) {
    int p;
    cin >> p;
    rep(_, p) {
      int x;
      cin >> x;
      a[i].push(x);
    }
  }
  queue<int> ans;
  queue<int> q;
  rep(i, n) if (!a[i].empty()) q.push(i);
  while (!q.empty()) {
    int idx = q.front();
    q.pop();
    int x = a[idx].front();
    a[idx].pop();
    ans.push(x);
    if (!a[idx].empty()) q.push(idx);
  }
  while (!ans.empty()) {
    cout << ans.front() << ' ';
    ans.pop();
  }
  cout << endl;
  return 0;
}