#include <bits/stdc++.h>
using namespace std;
template <class T>
void splitstr(const string &s, vector<T> &out) {
  istringstream in(s);
  out.clear();
  copy(istream_iterator<T>(in), istream_iterator<T>(), back_inserter(out));
}
template <class T>
T gcd(T a, T b) {
  return b ? gcd(b, a % b) : a;
}
static void redirect(int argc, const char **argv) {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  if (argc > 1) {
    static filebuf f;
    f.open(argv[1], ios::in);
    cin.rdbuf(&f);
    if (!cin) {
      cerr << "Failed to open '" << argv[1] << "'" << endl;
      exit(1);
    }
  }
  if (argc > 2) {
    static filebuf f;
    f.open(argv[2], ios::out | ios::trunc);
    cout.rdbuf(&f);
    if (!cout) {
      cerr << "Failed to open '" << argv[2] << "'" << endl;
    }
  }
}
static inline void setbit(int &v, int b) { v |= 1 << b; }
static inline bool getbit(int v, int b) { return v & (1 << b); }
static int N;
static int best;
static void recurse(const array<int, 22> &t, int pos, int mask) {
  if (pos == N) {
    if (count(begin(t), end(t), (1 << N) - 1) == N &&
        __builtin_popcount(mask) < __builtin_popcount(best))
      best = mask;
  } else {
    recurse(t, pos + 1, mask);
    array<int, 22> t2 = t;
    for (int i = 0; i < N; i++)
      if (getbit(t[pos], i)) t2[i] |= t[pos];
    recurse(t2, pos + 1, mask | (1 << pos));
  }
}
int main(int argc, const char **argv) {
  redirect(argc, argv);
  int M;
  cin >> N >> M;
  array<int, 22> orig{{}};
  for (int i = 0; i < N; i++) setbit(orig[i], i);
  for (int i = 0; i < M; i++) {
    int u, v;
    cin >> u >> v;
    u--;
    v--;
    setbit(orig[u], v);
    setbit(orig[v], u);
  }
  best = (1 << N) - 1;
  recurse(orig, 0, 0);
  cout << __builtin_popcount(best) << '\n';
  for (int i = 0; i < N; i++)
    if (getbit(best, i)) cout << i + 1 << ' ';
  cout << '\n';
  return 0;
}
