from math import lcm

def root(x):
    if P[x] < 0: return x
    P[x] = root(P[x])  # 経路圧縮
    return P[x]

def unite(x, y):
    x = root(x)
    y = root(y)
    if x == y: return
    if x > y: x, y = y, x
    P[x] += P[y]
    P[y] = x

def same(x, y):
    return root(x) == root(y)

def size(x):
    x = root(x)
    return -P[x]


N, M = map(int, input().split())
P = [-1] * N

P1 = list(range(N))
for _ in range(M):
    t, *S = map(int, input().split())
    s0 = P1[S[0] - 1]
    n = len(S)
    for i in reversed(range(n)):
        if i == 0:
            P1[S[(i + 1) % t] - 1] = s0
            continue
        P1[S[(i + 1) % t] - 1] = P1[S[i] - 1]

for i, p in enumerate(P1):
    unite(i, p)
ans = 1
for i in range(N):
    if i == root(i):
        ans = lcm(ans,size(i))
print(ans)