N=int(input())
P=[[] for i in range(N)]
na=0
for _ in range(N):
    buf=[int(i) for i in input().split()]
    P[i]=buf[1:]
    na=max(buf[0],na)
for i in range(na):
    for j in range(N):
        try:
            print(P[j][i],end=' ')
        except:
            continue
print()