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#!/usr/bin/env python3
from fractions import Fraction
from math import gcd

n = int(input())
edges = []
for _ in range(n):
    l = list(map(lambda s: int(s)-1, input().strip().split()))
    assert len(l) == l[0] + 2
    edges.append(l[1:])

freqact = [Fraction(0,1)]*n
freq_reset = [Fraction(0,1)]*n

freqact[0] = Fraction(1,1)

nww = 1
for i in range(n):
    out_edges = len(edges[i])
    if out_edges > 0:
        freq_reset[i] = freqact[i] * Fraction(1, out_edges)
    if out_edges > 1:
        nww = nww // gcd(nww, freq_reset[i].denominator) * freq_reset[i].denominator
    for e in edges[i]:
        freqact[e] += freq_reset[i]

print(nww)