#include <bits/stdc++.h>
using namespace std;
const long long mod = 1000000007;
long long powmod(long long a, long long b) {
  long long res = 1;
  a %= mod;
  assert(b >= 0);
  for (; b; b >>= 1) {
    if (b & 1) res = res * a % mod;
    a = a * a % mod;
  }
  return res;
}
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
int t, n, m, u, v, g[30], ret, rew, mark[30], f[30], pa[30][30];
int find(int x) { return f[x] == x ? x : f[x] = find(f[x]); }
void dfs(int S, int u, int v) {
  if (v >= ret) return;
  if (u == n) {
    bool suc = 1;
    int ff = -1;
    for (int i = 0; i < n; i++)
      if (S & (1 << i)) {
        if (ff == -1)
          ff = find(i);
        else {
          if (find(i) != ff) {
            suc = 0;
            break;
          }
        }
      } else {
        if ((g[i] & S) == 0) {
          suc = 0;
          break;
        }
      }
    if (suc) {
      ret = v, rew = S;
    }
  } else {
    for (int i = 0; i < n; i++) pa[u][i] = f[i];
    int su = find(u);
    for (int i = 0; i < n; i++)
      if (g[u] & S & (1 << i)) f[find(i)] = su;
    dfs(S | (1 << u), u + 1, v + 1);
    for (int i = 0; i < n; i++) f[i] = pa[u][i];
    dfs(S, u + 1, v);
  }
}
void dfs(int u) {
  mark[u] = 0;
  for (int v = 0; v < n; v++)
    if ((g[u] & (1 << v)) && mark[v]) dfs(v);
  printf("%d ", u + 1);
}
int main() {
  scanf("%d%d", &n, &m);
  for (int i = 0; i < m; i++) {
    scanf("%d%d", &u, &v);
    --u;
    --v;
    g[u] |= (1 << v);
    g[v] |= (1 << u);
  }
  if (m == n * (n - 1) / 2) {
    puts("0");
    return 0;
  }
  ret = n + 1;
  for (int i = 0; i < n; i++) g[i] |= (1 << i), f[i] = i;
  dfs(0, 0, 0);
  printf("%d\n", ret);
  for (int i = 0; i < n; i++)
    if (rew & (1 << i)) {
      mark[i] = 1;
    }
  for (int i = 0; i < n; i++)
    if (mark[i]) {
      dfs(i);
      return 0;
    }
}
