from fractions import gcd
R=range;N=input();A=R(N);S=1
for i in R(input()):x,y=map(int,raw_input().split());A[x-1],A[x]=A[x],A[x-1]
M={A[i]:i for i in R(N)}
while N:
	N-=1;h=M[N];C=1
	while h!=N:C+=1;h=M[h]
	S=S*C/gcd(S,C)
print S