from collections import *

N = int(input())
A = []
ans = []
for i in range(N):
    A.append(deque(map(int, input().split())))
    A[i].popleft()
    
for _ in range(105):
    for i in range(N):
        if A[i]:
            ans.append(A[i].popleft())
            
print(*ans)