N = int(input())
P = []
A = []

for _ in range(N):
    p, *a = map(int, input().split())
    P.append(p)
    A.append(a)

M = max(P)
res = []

for i in range(M):
    for j in range(N):
        if len(A[j]) > i:
            res.append(A[j][i])

print(*res)