import sys
input = sys.stdin.readline
from collections import deque

N = int(input())
ll = []

for _ in range(N):
    PA = list(map(int, input().split()))
    A = PA[1:]
    ll.append(deque(A))

ans = []

while True:
    flag = True
    
    for ll_i in ll:
        if len(ll_i) != 0:
            flag = False
            ans.append(ll_i.popleft())
            
    if flag:
        break

print(*ans)