import sys

sys.setrecursionlimit(10 ** 6)
from bisect import *
from collections import *
from heapq import *

int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.readline())
def MI(): return map(int, sys.stdin.readline().split())
def MI1(): return map(int1, sys.stdin.readline().split())
def MF(): return map(float, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LF(): return list(map(float, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
dij = [(0, 1), (1, 0), (0, -1), (-1, 0)]

def gcd(a, b):
    while b: a, b = b, a % b
    return a

def lcm(a, b):
    return a * b // gcd(a, b)

def main():
    def swap(x, y):
        aa[x], aa[y] = aa[y], aa[x]

    n = II()
    k = II()
    # 一回でどこへいくかシミュレーションする
    aa = list(range(n))
    for _ in range(k):
        x, y = MI1()
        swap(x, y)
    # それぞれの開始点が何回で戻ってくるかの周期を求める
    # その最小公倍数が答え
    vis = [False] * n
    ans = 1
    for i in range(n):
        if vis[i]: continue
        t = 0
        while not vis[i]:
            vis[i] = True
            t += 1
            i = aa[i]
        ans = lcm(ans, t)
    print(ans)

main()