# No.893 お客様を誘導せよ
n = int(input())
p = []
a = []
queue = []

for i in range(n):
    tmp = input().split()
    p.append(int(tmp[0]))
    a.append(tmp[1:])

while len(queue) < sum(p):
    for i in range(n):
        if len(a[i]) > 0:
            queue.append(a[i][0])
            a[i] = a[i][1:]
        
s = ''

for k in queue:
    s += k + ' '

print(s[:-1])