#include <bits/stdc++.h>

using namespace std;

ifstream fin("pamant.in");
ofstream fout("pamant.out");

int n, m, cnt, minim, d[100005], f[100005];
bool viz[100005];
vector <int> v[100005], a, b;

void DFS(int nod, int last)
{
     viz[nod] = 1;
    d[nod] = f[nod] = ++cnt;
    minim = min(minim, nod);
    bool ok = 0;
    for(int i = 0; i < v[nod].size(); i++)
    {
        int child = v[nod][i];
        if(child == last) continue;
        if(!viz[child]) DFS(child, nod);

        f[nod] = min(f[nod], f[child]);

        if(!ok && v[nod].size() > 1 && f[nod] < f[child])
            b.push_back(nod), ok = 1;

    }



}

int main()
{
    fin >> n >> m;

    for(int i = 1; i <= m; i++)
    {
        int a, b;
        fin >> a >> b;

        v[a].push_back(b);
        v[b].push_back(a);
    }

    for(int i = 1; i <= n; i++)
    {
        if(!viz[i])
        {
            minim = 100005;
            DFS(i, 0);
            a.push_back(minim);
        }
    }
    sort(a.begin(), a.end());
     sort(b.begin(), b.end());
    fout << a.size() << '\n';
    for(int i = 0; i < a.size(); i++)
        fout << a[i] << " ";
    fout << '\n' << b.size() << '\n';
   for(int i = 0; i < b.size(); i++)
        fout << b[i] << " ";
    return 0;
}