N = int(input())
L = [[int(l) for l in input().split()] for _ in range(N)]

ans = []
p = 0
for i in range(N):
    p = max(p, L[i][0])
    L[i].pop(0)

for _ in range(p):
    for j in range(N):
        if len(L[j]) == 0:
            continue
        ans.append(str(L[j][0]))
        L[j].pop(0)

print(" ".join(ans))