def gcd(a, b):
	if a == 0:
		return b
	else:
		return gcd(b%a, a)

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

N = int(input())
K = int(input())

a = [i for i in range(N)]

for i in range(K):
    x = int(input().split()[0])
    a[x], a[x-1] = a[x-1], a[x]

ans = 1
for i in range(N):
    x = i
    cnt = 0
    while True:
        cnt+=1
        x = a[x]
        if x == i:
            break
    ans = lcm(ans, cnt)

print(ans)