//ac
#include
#include
#include
#include
using namespace std;
int flag;
void op(int now, int g, vector& visited, vector >& stu, vector >& cor) {
if (flag) return;
visited[now] = g;
for (int i = 0; i < cor[now].size(); ++i) {
int s = cor[now][i];
for (int j = 0; j < 2; ++j) {
int t = stu[s][j];
if (t == now) continue;
if (visited[t]) {
if (visited[t] == g) {
flag = 1;
return;
}
} else {
op(t, 3 - g, visited, stu, cor);
}
}
}
}
int main() {
int n, m;
cin >> m >> n;
vector > stu(n);
vector > cor(m);
for (int i = 0; i < n; ++i) {
int a, b;
cin >> a >> b;
--a, --b;
stu[i].push_back(a), stu[i].push_back(b);
cor[a].push_back(i), cor[b].push_back(i);
}
vector visited(m, 0);
flag = 0;
op(0, 1, visited, stu, cor);
for (int i = 1; i < m; ++i) {
if (visited[i]) continue;
op(i, 1, visited, stu, cor);
}
if (flag) cout << "no" << endl;
else {
cout << "yes" << endl;
vector out;
for (int i = 0; i < m; ++i) {
if (visited[i] == 1) out.push_back(i);
}
cout << out.size() << endl;
for (int j = 0; j < out.size(); ++j) {
if (j) cout << ' ';
cout << out[j] + 1;
}
cout << endl;
}
return 0;
}