#include <bits/stdc++.h>
using namespace std;
void err(istream_iterator<string> it) {}
template <typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
  cout << *it << " = " << a << '\n';
  err(++it, args...);
}
const long long mod = 1e9 + 7;
set<int> adj[100001];
vector<int> s1[2], hei(100001, 0);
bool exist = true;
vector<bool> vis(100001, false);
void bfs(int v) {
  if (adj[v].size() == 0) return;
  queue<int> q;
  q.push(v);
  hei[v] = 1;
  vis[v] = true;
  s1[1].push_back(v);
  while (not q.empty()) {
    int u = q.front();
    q.pop();
    for (int x : adj[u]) {
      if (not vis[x]) {
        vis[x] = true;
        hei[x] = hei[u] + 1;
        q.push(x);
        s1[hei[x] % 2].push_back(x);
      } else if (hei[u] % 2 == hei[x] % 2) {
        exist = false;
        return;
      }
    }
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
  int n, m;
  cin >> n >> m;
  for (__typeof(m) i = (0) - (0 > m); i != (m) - (0 > m);
       i += 1 - 2 * (0 > m)) {
    int x, y;
    cin >> x >> y;
    adj[x].insert(y);
    adj[y].insert(x);
  }
  for (__typeof(n + 1) i = (1) - (1 > n + 1); i != (n + 1) - (1 > n + 1);
       i += 1 - 2 * (1 > n + 1)) {
    if (not vis[i]) bfs(i);
  }
  if (exist) {
    cout << s1[0].size() << '\n';
    for (int u : s1[0]) cout << u << ' ';
    cout << '\n' << s1[1].size() << '\n';
    for (int u : s1[1]) cout << u << ' ';
  } else
    cout << -1 << '\n';
  return 0;
}
