text: #include <bits/stdc++.h>
  // #include <atcoder/all>
  // using namespace atcoder;
  typedef long long ll;
  typedef long double ld;
  #define rep(i,n) for(ll i=0;i<(n);i++)
  #define repr(i,n) for(ll i=(n-1);i>=0;i--)
  #define all(x) x.begin(),x.end()
  #define br cout << '\n';
  using namespace std;
  const long long INF = 8e18;
  const long long MOD = 1e9+7;
  using Graph = vector<vector<ll>>;
  template<class T> inline bool chmin(T &a, T b) { if(a > b){ a = b; return true;} return false;}
  template<class T> inline bool chmax(T &a, T b) { if(a < b){ a = b; return true;} return false;}
  ll ceilll(ll a, ll b) {return (a + b-1) / b;} // if(a%b != 0) (a/b) + 1
  ll get_digit(ll a) {ll digit = 0; while(a != 0){a /= 10; digit++;} return digit;} // a != 0
  template<typename T> void vecdbg(vector<T>& v){ rep(i, v.size()){cerr << v[i] << ' ';} cerr << '\n';}
  template<typename T> void vecvecdbg(vector<vector<T>>& v){ rep(i, v.size()){rep(j, v[i].size()){cerr << v[i][j] << ' ';} cerr << '\n';}}
  ll POW(ll a, ll n){ ll res = 1; while(n > 0){ if(n & 1){ res = res * a; } a *= a; n >>= 1; } return res; }
  using P = pair<ll, ll>;
  const double PI = acos(-1);
  
  // 0 false, 1 true 
  // string number to int : -48 or - '0'
  // a to A : -32
  // ceil(a)  1.2->2.0
  // c++17	g++ -std=c++17 a.cpp
  // global vector -> 0 initialization
  // DONT FORGET TO INTIALIZE
  // The type of GRID is CHAR. DONT USE STRING
  // If the result in local and judge is different, USE CODETEST!!
  // (a * b)over flow?   if(a > INF / b){ /* overflow */}
  // for(auto& i: mp) &&&&&&&&&&&&&
  
  int main() {
      std::cout << std::fixed << std::setprecision(15);
      ll n, m; cin >> n >> m;
      vector<vector<ll>> g(n);
      vector<vector<ll>> g2(n);
  
      map<P, ll> mp;
  
      rep(i, m){
          ll a, b; cin >> a >> b; a--; b--;
          g[a].push_back(b); g[b].push_back(a);
          mp[{a, b}]++; mp[{b, a}]++;
      }
  
      map<P, ll> mp2;
      rep(i, m){
          ll c, d; cin >> c >> d; c--; d--;
          g2[c].push_back(d); g2[d].push_back(c);
          mp2[{c, d}]++; mp2[{d, c}]++;
      }
  
      vector<ll> p(n);
      rep(i, n){
          p[i] = i;
      }
  
      if(m == 0){
          cout << "Yes" << endl; return 0;
      }
  
      do{
          bool f = true;
          for(auto&i : mp){
              ll l = i.first.first, r = i.first.second;
              if(mp2.count({p[l], p[r]}) == 0 && mp2.count({p[r], p[l]}) == 0){
                  f = false;
              }
          }
          if(f){
              cout << "Yes" << endl; return 0;
          }
  
      }while(next_permutation(p.begin(), p.end()));
  
      cout << "No" << endl;
  
  }