#include <bits/stdc++.h>
using namespace std;
vector<vector<int>> g;
bool cyc = 0;
vector<int> vis;
void dfs1(int v,int p)
{
vis[v] = 1;
for(auto u:g[v])
{
if(!vis[u])
dfs1(u,v);
else if(u != p)
cyc = 1;
}
return ;
}
pair<int,int> dfs2(int v,int p)
{
pair<int,int> ans ={v,0};
for(auto u:g[v])
{
if(u != p)
{
pair<int,int> ne = dfs2(u,v);
if(ne.second + 1 > ans.second)
{
ans = {ne.first,ne.second+1 };
}
}
}
return ans;
}
vector<int> path;
bool dfs3(int v,int p,int to)
{
path.push_back(v);
if(v == to)
{
return true;
}
for(auto u:g[v])
{
if(u != p)
{
if(dfs3(u,v,to))
return true;
}
}
path.pop_back();
return false;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
int n,m;
cin >> n >> m;
g.resize(n);
vis.resize(n);
for(int j = 0;j < m;++j)
{
int u,v;
cin >> u >> v;
u--;
v--;
g[u].push_back(v);
g[v].push_back(u);
}
dfs1(0,-1);
if(cyc)
{
cout << "NO\n";
return 0;
}
else
{
int st = dfs2(0,-1).first;
int fn = dfs2(st,-1).first;
dfs3(st,-1,fn);
vector<bool> isin(n,0);
for(int j = 0;j < path.size();++j)
{
isin[path[j]] = 1;
}
int no = 0;
for(int j = 0;j < n;++j)
{
if(!isin[j])
{
if(g[j].size() != 1)
{
for(auto u:g[j])
{
if(!isin[u] && g[u].size() > 1)
{
no = 1;
}
}
}
}
}
if(no)
{
cout << "NO\n";
}
else
{
cout << "YES\n";
if(n == 1)
{
cout << "1\n1";
return 0;
}
else if(n == 2)
{
cout << "2\n1 1\n";
return 0;
}
vector<int> ans;
for(int i = 1;i+1 < path.size();++i)
{
ans.push_back(path[i]);
for(auto u:g[path[i]])
{
if(!isin[u] && g[u].size() > 1)
{
ans.push_back(u);
ans.push_back(path[i]);
}
}
}
for(int j = path.size()-2;j > 0;--j)
ans.push_back(path[j]);
cout << ans.size() << "\n";
for(auto c:ans)
cout << c+1 << ' ';
}
}
}
