/* -*- coding: utf-8 -*-
 *
 * 3694.cc:  No.3694 迥ｬ迪ｿ縺ｮ莉ｲ - yukicoder
 */

#include<cstdio>
#include<vector>
#include<queue>
#include<algorithm>

using namespace std;

/* constant */

const int MAX_N = 200000;
const int MAX_M = 200000;

/* typedef */

using vi = vector<int>;
using qi = queue<int>;

/* global variables */

vi nbrs[MAX_N];
int ds[MAX_N];

/* subroutines */

/* main */

int main() {
  int n, m;
  scanf("%d%d", &n, &m);
  for (int i = 0; i < m; i++) {
    int u, v;
    scanf("%d%d", &u, &v);
    u--, v--;
    nbrs[u].push_back(v);
    nbrs[v].push_back(u);
  }

  fill(ds, ds + n, -1);
  for (int rt = 0; rt < n; rt++)
    if (ds[rt] < 0) {
      ds[rt] = 0;
      qi q;
      q.push(rt);

      while (! q.empty()) {
	int u = q.front(); q.pop();
	for (auto v: nbrs[u]) {
	  if (ds[v] < 0)
	    ds[v] = ds[u] ^ 1, q.push(v);
	  else if (ds[v] == ds[u]) {
	    puts("No");
	    return 0;
	  }
	}
      }
    }

  puts("Yes");
  return 0;
}