#include <iostream>

using namespace std;

int n, m;
int cnt[100005];

int main(void)
{
  cin >> n >> m;
  int u, v;
  for(int i =1; i <= m; i++){
    cin >> u >> v;
    cnt[u]++, cnt[v]++;
  }
  for(int i = 1; i <= n; i++){
    if(cnt[i]%2){
      cout << "NO" << endl;
      return 0;
    }
  }
  cout << "YES" << endl;
  return 0;
}