n = int(input())

P = [0] * n
A = [[0] for _ in range(n)]

ans = []
for i in range(n):
    a = input().split()
    P[i] = int(a[0])
    A[i] = a[1:]
    
m = max(P)
for i in range(m):
    for j in range(n):
        try:
            ans.append(A[j][i])
        except IndexError:
            continue

print(*ans)