#include <bits/stdc++.h>
#define rep(i,n) for(int i=(0);i<(n);i++)

using namespace std;

typedef long long ll;

int main()
{
	cin.tie(0);
	ios::sync_with_stdio(false);

	int n;
	cin >> n;

	queue<int> A[n];
	rep(i, n){
		int p;
		cin >> p;

		rep(j, p){
			int x;
			cin >> x;
			A[i].push(x);
		}
	}

	bool updated = true;
	while(updated){
		updated = false;
		rep(i, n){
			if(A[i].empty()) continue;
			updated = true;
			cout << A[i].front() << " ";
			A[i].pop();
		}
	}

	cout << endl;
}