const d = require('fs').readFileSync(0, 'utf8').split(/\s+/);
let p = 0;
const n = +d[p++], m = +d[p++];
const head = new Int32Array(n + 1).fill(-1);
const nxt = new Int32Array(2 * m), to = new Int32Array(2 * m);
let ec = 0;
for (let i = 0; i < m; i++) {
  const a = +d[p++], b = +d[p++];
  to[ec] = b; nxt[ec] = head[a]; head[a] = ec++;
  to[ec] = a; nxt[ec] = head[b]; head[b] = ec++;
}
const color = new Int8Array(n + 1).fill(-1);
const q = new Int32Array(n);
let ans = 'Yes';
for (let s = 1; s <= n && ans === 'Yes'; s++) {
  if (color[s] !== -1) continue;
  color[s] = 0;
  let qh = 0, qt = 0; q[qt++] = s;
  while (qh < qt) {
    const v = q[qh++];
    for (let e = head[v]; e !== -1; e = nxt[e]) {
      const u = to[e];
      if (color[u] === -1) { color[u] = color[v] ^ 1; q[qt++] = u; }
      else if (color[u] === color[v]) { ans = 'No'; qh = qt; break; }
    }
  }
}
console.log(ans);