#include using namespace std; typedef long long ll; #define rep(i, n) for(ll i = 0, i##_len = (n); i < i##_len; i++) #define reps(i, s, n) for(ll i = (s), i##_len = (n); i < i##_len; i++) #define rrep(i, n) for(ll i = (n) - 1; i >= 0; i--) #define rreps(i, e, n) for(ll i = (n) - 1; i >= (e); i--) #define all(x) (x).begin(), (x).end() #define sz(x) ((ll)(x).size()) #define len(x) ((ll)(x).length()) int main() { cin.tie(0); ios::sync_with_stdio(false); // ifstream in("input.txt"); // cin.rdbuf(in.rdbuf()); ll n; cin >> n; vector> vq(n); ll cnt = 0; rep(i, n) { ll p; cin >> p; rep(ii, p) { ll a; cin >> a; vq[i].push(a); } cnt = max(cnt, p); } vector ans; rep(i, cnt) { rep(ii, n) { if (sz(vq[ii]) == 0) continue; ans.push_back(vq[ii].front()); vq[ii].pop(); } } rep(i, sz(ans)) { printf("%lld%s", ans[i], (i == (sz(ans) - 1)) ? "\n" : " "); } return 0; }