#include <cstdio>
#include <queue>
#define rep( i, n, m ) for(int i = ( n ); i < ( m ); i++)

int main( void ){
	int n;
	if (!scanf( "%d", &n ))
		return 0;
	int* * array_ptr = new int*[n];
	int* counters = new int[n*2];

	rep( i, 0, n ){
		int num;
		if (!scanf( "%d", &num ))
			return 0;
		array_ptr[i] = new int[num];
		rep(j,0,num){
			if (!scanf( "%d", array_ptr[i]+j ))
				return 0;
		}
		counters[2*i] = 0;
		counters[2*i+1] = num;
	}
	bool is_finished = false;
	std::queue<int> costomers;
	while(!is_finished){
		is_finished = true;
		rep(i,0,n){
			if (counters[2*i] != counters[2*i+1]){
				is_finished = false;
				costomers.push(array_ptr[i][counters[2*i]]);
				counters[2*i]++;
			}
		}
	}
	while(!costomers.empty()){
		printf("%d ", costomers.front());
		costomers.pop();
	}
	printf("\n");
	return 0;
}