#include <bits/stdc++.h>
#define rep(i, n) for(ll i = 0; i < ll(n); ++i)
#define rep2(i, s, n) for(ll i = ll(s); i < ll(n); ++i)
#define rrep(i, n) for(ll i = ll(n) - 1; i >= 0; --i)
#define rrep2(i, n, t) for(ll i = ll(n) - 1; i >= ll(t); --i)
#define pb push_back
#define eb emplace_back
#define all(a) a.begin(), a.end()
#define SZ(a) int(a.size())
using namespace std;
using ll = long long;
using P = pair<int, int>;
using vi = vector<int>;
using vvi = vector<vi>;
using vl = vector<ll>;
using vvl = vector<vl>;
using vp = vector<P>;
using vvp = vector<vp>;
using vb = vector<bool>;
using vvb = vector<vb>;
using vs = vector<string>;
const int inf = 1001001001;
const ll linf = 1001001001001001001;
template<class T>
bool chmin(T &a, T b) {
if (a > b) {
a = b;
return true;
}
return false;
}
template<class T>
bool chmax(T &a, T b) {
if (a < b) {
a = b;
return true;
}
return false;
}
vi solve2(int n, vvi G) {
if (n == 1) return {1};
if (n == 2) return {1, 1};
auto dfs = [&](auto &dfs, int u, int p) -> vi {
vi res;
for (int v: G[u]) {
if (v == p) continue;
vi now = dfs(dfs, v, u);
if (SZ(now) > SZ(res)) res = now;
}
res.pb(u);
return res;
};
int a = dfs(dfs, 0, -1)[0];
vi dm = dfs(dfs, a, -1);
vi res;
rep2(i, 1, SZ(dm) - 1) {
res.pb(dm[i] + 1);
for (int j: G[dm[i]]) {
if (j == dm[i - 1] or j == dm[i + 1]) continue;
vi now = dfs(dfs, j, dm[i]);
if (SZ(now) >= 3) return {};
if (SZ(now) == 2) {
res.pb(now.back() + 1);
res.pb(dm[i] + 1);
}
}
}
vi rev = res;
reverse(all(rev));
res.insert(res.end(), all(rev));
return res;
}
vi solve(int n, vvi G) {
if (n == 1) return {1};
assert(n <= 20);
vi d(1 << n, inf);
vp pre(1 << n);
queue<int> q;
d[(1 << n) - 1] = 0;
q.push((1 << n) - 1);
while (not q.empty()) {
int now = q.front();
q.pop();
int nx = 0;
rep(i, n) {
for (int j: G[i]) {
if (now >> j & 1) nx |= 1 << i;
}
}
rep(i, n) {
if (~nx >> i & 1) continue;
nx -= 1 << i;
if (chmin(d[nx], d[now] + 1)) {
q.push(nx);
pre[nx] = {now, i};
}
nx += 1 << i;
}
}
if (d[0] == inf) return {};
vi ans;
int now = 0;
while (now < (1 << n) - 1) {
ans.pb(pre[now].second + 1);
now = pre[now].first;
}
reverse(all(ans));
return ans;
}
random_device seed_gen;
mt19937 engine(seed_gen());
int rnd(int mn, int mx) {
uniform_int_distribution<int> dist(mn, mx);
return dist(engine);
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr), cout.tie(nullptr);
// int n;
// cin >> n;
// rep(_, 10000) {
// vvi G(n);
// rep2(i, 1, n) {
// int j = rnd(0, i - 1);
// G[i].pb(j);
// G[j].pb(i);
// }
// if (solve(n, G).empty() != solve2(n, G).empty()) {
// cout << "#" << endl;
// rep(i, n) {
// for (int j: G[i]) {
// if (i < j) {
// cout << i << ' ' << j << endl;
// }
// }
// }
// }
// }
int n, m;
cin >> n >> m;
vvi G(n);
rep(i, m) {
int u, v;
cin >> u >> v;
--u, --v;
G[u].pb(v);
G[v].pb(u);
}
if (m > n - 1) {
cout << "NO" << endl;
return 0;
}
vi ans = solve2(n, G);
if (ans.empty()) {
cout << "NO" << endl;
return 0;
}
cout << "YES" << endl;
cout << SZ(ans) << endl;
rep(i, SZ(ans)) cout << ans[i] << (i < SZ(ans) - 1 ? ' ' : '\n');
}
