#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define REP(i, n)           for(int(i)=0;(i)<(n);++(i))
const int MOD = 1000000007;

int N, K, x[1010],y[1010];
int a[111];

int gcd(int n, int m){return m?gcd(m,n%m):n;}
int lcm(int n, int m){return n/gcd(n,m)*m;}

int main(){
    cin >> N >> K;
    REP(i,K){
        cin >> x[i] >> y[i];
        x[i]--, y[i]--;
    }

    REP(i,N){
        int k = i;
        REP(j,K){
            if(x[j] == k){ k = y[j]; continue; }
            if(y[j] == k){ k = x[j]; continue; }
        }
        a[i] = k;
    }
    int g = 1;
    REP(i,N){
        int c = 1, j = a[i];
        while(j != i){
            j = a[j];
            c++;
        }
        g = lcm(g,c);
    }
    cout << g << endl;
    return 0;
}