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

int main() {
  int n, m;
  cin >> n >> m;
  vector<vector<int>> G(n);
  for( int i = 0; i < m; i++ ) {
    int a, b;
    cin >> a >> b;
    a--, b--;
    G[a].push_back(b);
    G[b].push_back(a);
  }
  string ans = "Yes";
  vector<int> c(n, -1);
  auto dfs = [&](auto dfs, int cur) -> void {
    for( int &nxt : G[cur] ) {
      if( c[nxt] == -1 ) {
        c[nxt] = 1-c[cur];
        dfs(dfs, nxt);
      }else if( c[nxt] == c[cur] ) {
        ans = "No";
      }
    }
  };
  for( int i = 0; i < n; i++ ) {
    if( c[i] == -1 ) {
      c[i] = 0;
      dfs(dfs, i);
    }
  }
  cout << ans << endl;
}