#include <bits/stdc++.h>
using namespace std;
const long long maxn = 2000100, mod = 1e9 + 7, maxa = 20100, maxb = 23,
                base = 737, base2 = 3079, mod2 = 242121643;
const long long inf = 2e18 + 13;
long long max(long long x, long long y) { return (x > y ? x : y); }
long long min(long long x, long long y) { return (x < y ? x : y); }
long long adj[1 << maxb];
long long dp[1 << maxb];
vector<long long> v[maxb];
long long maks;
void dfs(long long x) {
  maks -= (1 << x);
  for (auto u : v[x]) {
    if ((maks >> u) & 1) {
      dfs(u);
    }
  }
}
int32_t main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long n, m;
  cin >> n >> m;
  if (m == (n * (n - 1)) / 2) {
    cout << 0 << endl;
    return 0;
  }
  for (long long i = 0; i < m; i++) {
    long long x, y;
    cin >> x >> y;
    x--;
    y--;
    adj[x] += (1 << y);
    adj[y] += (1 << x);
    v[x].push_back(y);
    v[y].push_back(x);
  }
  long long ok = 0;
  for (long long i = 0; i < n; i++) {
    adj[i] += (1 << i);
    ok += (1 << i);
  }
  long long ans = inf, res = 0;
  for (long long mask = 1; mask < (1 << n); mask++) {
    dp[mask] = dp[mask ^ (((mask) & (-mask)))] | adj[__builtin_ctz(mask)];
    long long t = __builtin_popcount(mask);
    if (dp[mask] == ok && t < ans) {
      maks = mask;
      dfs(__builtin_ctz(mask));
      if (maks == 0) {
        ans = t;
        res = mask;
      }
    }
  }
  cout << ans << endl;
  for (long long i = 0; i < n; i++) {
    if ((res >> i) & 1) {
      cout << i + 1 << ' ';
    }
  }
  cout << endl;
  return 0;
}
