#include <bits/stdc++.h>
using namespace std;
const long long INF = 1e18;
const int inf = 1e9;
const long double eps = 1e-7;
const long double pi = acos(-1);
const int dx[8] = {0, 2, 1, 0, -2, -1, 1, 2};
const int dy[8] = {2, 0, 1, -2, 0, -1, 2, 1};
const int N = 23;
const int MAXN = 1e5;
const int mod = 1e9 + 7;
int g[N];
int dp[(1 << N)], p[(1 << N)];
int main() {
  int n, m;
  cin >> n >> m;
  if (m == n * (n - 1) / 2) {
    cout << 0;
    return 0;
  }
  for (int i = 1; i <= m; i++) {
    int u, v;
    cin >> u >> v;
    u--, v--;
    g[u] |= (1 << v);
    g[v] |= (1 << u);
  }
  for (int i = 0; i < n; i++) {
    g[i] |= (1 << i);
  }
  for (int i = 0; i < (1 << n); i++) {
    dp[i] = inf;
  }
  dp[0] = 0;
  for (int i = 0; i < n; i++) {
    dp[g[i]] = 1;
    p[g[i]] = 0;
  }
  for (int mask = 1; mask < (1 << n); mask++) {
    if (dp[mask] == inf) continue;
    for (int i = 0; i < n; i++) {
      if ((mask >> i) & 1) {
        int nmask = (mask | g[i]);
        if (dp[nmask] > dp[mask] + 1) {
          dp[nmask] = dp[mask] + 1;
          p[nmask] = mask;
        }
      }
    }
  }
  int mask = (1 << n) - 1;
  vector<int> ans;
  cout << dp[mask] << "\n";
  while (mask) {
    int pmask = p[mask];
    if (p[mask] == 0) {
      for (int i = 0; i < n; i++) {
        if (mask == g[i]) {
          ans.push_back(i);
          break;
        }
      }
      break;
    }
    for (int i = 0; i < n; i++) {
      if ((pmask >> i) & 1) {
        int nmask = (pmask | g[i]);
        if (nmask == mask) {
          ans.push_back(i);
          break;
        }
      }
    }
    mask = pmask;
  }
  reverse(ans.begin(), ans.end());
  for (int i = 0; i < (int)ans.size(); i++) {
    cout << ans[i] + 1 << " ";
  }
}
