#include #include #include #include #define FORR(i,b,e) for(int i=(b);i<(int)(e);++i) #define FOR(i,e) FORR(i,0,e) #define ALL(c) begin(c), end(c) #define dump(var) cerr << #var ": " << var << "\n" #define dumpc(con) for(auto& e: con) cerr << e << " "; cerr<<"\n" using namespace std; int gcd(int m, int n) { int t; while (m != 0) { t = m; m = n % m; n = t; } return n; } int lcm(int m, int n) { return m * n / gcd(m, n); } int main() { cin.tie(0); ios::sync_with_stdio(false); int N, K; cin >> N >> K; vector X(K), Y(K); FOR(i, K) { cin >> X[i] >> Y[i]; X[i]--; Y[i]--; } vector m(N); FOR(i, N) m[i] = i; FOR(i, K) { swap(m[X[i]], m[Y[i]]); } int common = 1; FOR(i, N) { int cnt = 1; int p = m[i]; while (p != i) { p = m[p]; cnt++; } // dump(cnt); common = lcm(cnt, common); } cout << common << endl; return 0; }