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

#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rrep(i,n) for(int i=(int)(n-1);i>=0;i--)
#define ALL(v) v.begin(),v.end()
#define RALL(v) v.rbegin(),v.rend()
template <class T> using V=vector<T>;
template <class T> using VV=V<V<T>>;
using u128=__int128_t;
using ll=long long;

V<int> G[20020];
 
int main(){
  ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
  random_device rd;
  mt19937_64 rnd(rd());
  
  int n,m;
  cin>>n>>m;
  rep(i,m){
    int a,b;
    cin>>a>>b;
    a--,b--;
    G[a].push_back(b);
    G[b].push_back(a);
  }
  rep(_,200){
    uniform_int_distribution<int> ud(0,4);
    V<int> color(n);
    rep(i,n) color[i]=ud(rnd);
    VV<bool> dp(1<<5,V<bool>(n));
    dp[1<<color[0]][0]=1;
    for(int s=1;s<(1<<5)-1;s++){
      rep(v,n){
        if(dp[s][v]==0) continue;
        for(auto nv:G[v]){
          if(s>>color[nv]&1) continue;
          dp[s|(1<<color[nv])][nv]=1;
        }
      }
    }
    rep(i,n){
      if(dp[(1<<5)-1][i]){
        for(auto nv:G[i]){
          if(nv==0){
            cout<<"YES\n";
            return 0;
          }
        }
      }
    }
  }
  cout<<"NO\n";
    
  return 0;
}