cycledirectedgraph

#include<bits/stdc++.h>
using namespace std;

#define fast ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL)
#define ll long long
#define ld long double
#define pb push_back
#define fe first
#define se second
#define nl "\n"
#define pp pair < ll , ll >
#define sz(x) (ll)x.size()
#define st(x) sort(x.begin(),x.end())
#define rst(x) sort(x.rbegin(), x.rend())
#define all(x) x.begin(),x.end()
long double pi = 3.14159265358979323;

const double EPS = 1e-12;
const int N = 1e6 + 5;
//Just A Gentle Reminder about MOD
const int mod = 1e9 + 7;

int vis[N];
vector < ll > v[N];
//Cycle in a directed edge
bool cycle ;

void dfs(ll s){

    vis[s] = 1;

    for(auto it : v[s]){
        if(!vis[it]){
            dfs(it);
        }
        else if(vis[it] == 1){
            cycle = 1;
            return  ;
        }
    }
    vis[s] = 2;
}


int main()
{
    fast;
    ll n , m;
    cin >> n >> m ;
    for(int i = 0 ; i < m ; i++ ){
        ll a , b;
        cin >> a >> b;
        v[a].pb(b);
    }
    dfs(1);
    if(cycle)cout << "Cycle Found\n";
    else cout << "NO";






















    return 0;
//It's not end it yet
}