#include <fstream>
#include <iostream>
#include <vector>
#include <string>
#include <iomanip>
#include <algorithm>
#include <vector>
#include <stack>
#include <set>
#include <queue>
#include <stack>
#include <map>
#include <deque>
#include <bitset>
#include <tuple>
//#include <math.h>
#define ull int long long
#define ll long long
#define ld long double
#define MAX 2e9
#define MIN -2e9
#define PI 3.14159265
#define fst first
#define scd second
#define mp make_pair
#define forn(i, x) for(int i = 0; i < x; i++)
#define pb push_back

using namespace std;
int n, m, s, t;
vector< vector< int > > g;
vector< int > color;
int st = -1, ed = -1;
vector< int> ans;

bool dfs(int v) {
   color[v] = 1;
   for(int i = 0; i < g[v].size(); i++) {
      int to = g[v][i];
      if(color[to] == 0) {
         bool state =  dfs(to);
         if(state) {
               ans.pb(v);
               return true;
         }
      } else if(color[to] == 1) {
         st = v;
         ans.pb(v);
         return  true;
      }
   }
   color[v] = 2;
   return false;
   }

int main() {

 //  freopen("cycle.in", "r", stdin);
  // freopen("cycle.out", "w", stdout);
   ios_base::sync_with_stdio(false);
   cin.tie(NULL);
   cin >> n >> m;
   g.resize(n + 1);
   color.resize(n + 1, 0);
   for(int i = 0; i < m; i++) {
      int a, b;
      cin >> a>> b;
      g[a].pb(b);
   }
   for(int i = 0; i <= n; i++) {
      if(dfs(i)) {
         cout << "YES\n";
         reverse(ans.begin(), ans.end());
         for(int j = 0; j < ans.size(); j++) {
            cout << ans[j] << " ";
         }
         return 0;
      }
   }
   cout << "NO";
    return 0;
}