#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; using ll = long long; constexpr int INF = 1001001001; constexpr int mod = 1000000007; // constexpr int mod = 998244353; template inline bool chmax(T& x, T y){ if(x < y){ x = y; return true; } return false; } template inline bool chmin(T& x, T y){ if(x > y){ x = y; return true; } return false; } struct StronglyConnectedComponents{ using G = vector>; G graph; G rev; int n; int scc_sz = 0; G scc_graph; vector scc_id; vector vs; vector visited; StronglyConnectedComponents() = default; StronglyConnectedComponents(int V) : n(V) { graph.resize(n); rev.resize(n); scc_id.assign(n, -1); visited.assign(n, false); } StronglyConnectedComponents(G& g) : graph(g), n(g.size()) { rev.resize(n); scc_id.assign(n, -1); visited.assign(n, false); for(int u = 0; u < n; ++u){ for(int v : graph[u]) rev[v].push_back(u); } } void resize(int V){ n = V; graph.resize(n); rev.resize(n); scc_id.assign(n, -1); visited.assign(n, false); } void add_edge(int u, int v){ graph[u].emplace_back(v); rev[v].emplace_back(u); } void dfs(int from){ visited[from] = true; for(int to : graph[from]){ if(!visited[to]) dfs(to); } vs.push_back(from); } void rdfs(int from, int k){ scc_id[from] = k; for(int to : rev[from]){ if(scc_id[to] == -1) rdfs(to, k); } } void build(){ for(int v = 0; v < n; ++v){ if(!visited[v]) dfs(v); } reverse(vs.begin(), vs.end()); for(int v : vs){ if(scc_id[v] == -1) rdfs(v, scc_sz++); } scc_graph.resize(scc_sz); for(int v = 0; v < n; ++v){ scc_graph[scc_id[v]].push_back(v); } return; } int size() { return scc_sz; } vector get_set(int k) { return scc_graph[k]; } int operator[](int v) { return scc_id[v]; } }; int main(){ ios::sync_with_stdio(false); cin.tie(nullptr); int N, K; cin >> N >> K; vector amida(N); for(int i = 0; i < N; ++i) amida[i] = i; for(int i = 0; i < K; ++i){ int X, Y; cin >> X >> Y; swap(amida[X - 1], amida[Y - 1]); } StronglyConnectedComponents g(N); for(int i = 0; i < N; ++i){ g.add_edge(amida[i], i); } g.build(); int sz = g.size(); ll LCM = 1; for(int i = 0; i < sz; ++i){ int x = g.get_set(i).size(); LCM = LCM / gcd(LCM, x) * x; } cout << LCM << endl; return 0; }