175

#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <cstdio>
#include <set>
#include <map>
#include <sstream>
#include <iterator>
#include <cmath>
#include <unordered_map>
#include <queue>

using namespace std;

void dfs(int u, int p, int dep, vector< vector<int> > &g,
         vector<int> &d, vector<int> &fup, vector<int> &dots){
    d[u] = fup[u] = dep;
    int sons = 0;
    bool isDot = false;
    for (int i = 0; i < g[u].size(); ++i){
        if(g[u][i] == p)
            continue;
        if(d[g[u][i]] >= 0)
            fup[u] = min(fup[u], d[g[u][i]]);
        else{
            dfs(g[u][i], u, dep + 1, g, d, fup, dots);
            fup[u] = min(fup[u], fup[g[u][i]]);
            if(u != p && fup[g[u][i]] >= d[u])
                isDot = true;
            sons++;
        }
    }
    if(u == p && sons > 1)
        isDot = true;

    if(isDot)
        dots.push_back(u);
}

int main(){
    ios_base::sync_with_stdio(false);

    int n, m;
    cin >> n >> m;
    vector< vector<int> > g(n);
    for (int i = 0; i < m; ++i){
        int x, y;
        cin >> x >> y;
        g[x - 1].push_back(y - 1);
        g[y - 1].push_back(x - 1);
    }

    vector<int> d(n, -1);
    vector<int> fup(n, -1);
    vector<int> dots;
    dfs(0, 0, 0, g, d, fup, dots);

    sort(dots.begin(), dots.end());

    cout << dots.size() << endl;
    for (int i = 0; i < dots.size(); ++i)
        cout << dots[i] + 1 << " ";

    cout << endl;
    return 0;
}