#include <bits/stdc++.h>
using namespace std;
const int INF = 1e9;
int n, m;
bool g[24][24];
int friends[24];
int dp[1 << 22];
int prev_state[1 << 22];
int person[1 << 22];
int main() {
  cin >> n >> m;
  int MAX = 1 << n;
  for (int i = 0; i < MAX; i++) {
    dp[i] = INF;
  }
  for (int i = 0; i < n; i++) {
    friends[i + 1] |= (1 << i);
    dp[1 << i] = 0;
  }
  for (int i = 0; i < m; i++) {
    int u, v;
    scanf("%d %d", &u, &v);
    g[u][v] = g[v][u] = 1;
    friends[u] |= (1 << (v - 1));
    friends[v] |= (1 << (u - 1));
  }
  for (int k = 0; k < MAX; k++) {
    if (dp[k] < INF) {
      for (int i = 1; i <= n; i++) {
        if ((k & friends[i]) == k) {
          dp[k | (1 << (i - 1))] = 0;
        }
      }
    }
  }
  for (int k = 0; k < MAX; k++) {
    if (dp[k] < INF) {
      for (int i = 1; i <= n; i++) {
        if (k & (1 << (i - 1))) {
          if (dp[k] + 1 < dp[k | friends[i]]) {
            dp[k | friends[i]] = dp[k] + 1;
            prev_state[k | friends[i]] = k;
            person[k | friends[i]] = i;
          }
        }
      }
    }
  }
  int ans = dp[MAX - 1];
  cout << ans << endl;
  int t = MAX - 1;
  while (ans--) {
    cout << person[t] << " ";
    t = prev_state[t];
  }
  return 0;
}
