/* -*- coding: utf-8 -*-
 *
 * 2202.cc:  No.2202 贅沢てりたまチキン - yukicoder
 */

#include<cstdio>
#include<vector>
#include<algorithm>
 
using namespace std;

/* constant */

const int MAX_N = 200000;

/* typedef */

typedef vector<int> vi;

/* global variables */

vi nbrs[MAX_N];
int ps[MAX_N], ds[MAX_N], cis[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 st = 0; st < n; st++)
    if (ds[st] < 0) {
      bool ok = false;
      ps[st] = -1, ds[st] = 0;
      for (int u = st; u >= 0;) {
	vi &nbru = nbrs[u];
	int up = ps[u];

	if (cis[u] < nbru.size()) {
	  int v = nbru[cis[u]++];
	  if (v != up) {
	    if (ds[v] < 0) {
	      ps[v] = u, ds[v] = ds[u] + 1;
	      u = v;
	    }
	    else if (! ((ds[u] - ds[v]) & 1))
	      ok = true;
	  }
	}
	else
	  u = up;
      }
      if (! ok) { puts("No"); return 0; }
    }

  puts("Yes");
  return 0;
}