#include <bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define rrep(i,n) for(int (i)=((n)-1);(i)>=0;(i)--)
#define itn int
#define all(x) (x).begin(),(x).end()
#define F first
#define S second
const long long INF = 1LL << 60;
const int MOD = 1000000007;
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
signed main(void){
    itn n; cin>>n;
    vector <queue<int> > vq(n);
    rep(i,n){
        itn x ; cin>>x;
        rep(j,x){
            itn a; cin>>a;
            vq[i].push(a);
        }
    }
    vector <int> ans;
    bool ok = false;
    while(!ok){
        ok = true;
        rep(i,n){
            if(vq[i].empty()) continue;
            else {
                ok = false;
                ans.push_back(vq[i].front());
                vq[i].pop();
            }
        }
    }
    rep(i,ans.size()){
        cout<<ans[i]<<' ';
    }
}