#include <bits/stdc++.h>
#include <atcoder/dsu>
using namespace std;
using ll = long long;
#define rep(i,n) for (int i=0;i<(int)(n);i++)

int main(){
  int n,m;
  cin>>n>>m;
  atcoder::dsu uf(2*n);
  rep(i,m){
    int a,b;
    cin>>a>>b;
    a--; b--;
    uf.merge(a,b+n);
    uf.merge(a+n,b);
  }
  int flg=1;
  rep(i,n){
    if(!uf.same(i,i+n)) flg=0;
  }
  cout<<(flg?"Yes":"No")<<endl;
}