#include <bits/stdc++.h>
using namespace std;
int n, m, a[1000000], f[10000000], ff[10000000], fff[10000000];
int main() {
  scanf("%d%d", &n, &m);
  for (int i = 1; i <= m; i++) {
    int x, y;
    scanf("%d%d", &x, &y);
    a[x] |= 1 << (y - 1);
    a[y] |= 1 << (x - 1);
  }
  if (m == n * (n - 1) / 2) {
    puts("0");
    return 0;
  }
  for (int i = 0; i < (1 << n); i++) f[i] = 10000;
  for (int i = 1; i <= n; i++) a[i] |= 1 << (i - 1);
  for (int i = 1; i <= n; i++) f[a[i]] = 1, ff[a[i]] = i, fff[a[i]] = 0;
  for (int i = 1; i < (1 << n); i++)
    for (int j = 1; j <= n; j++)
      if ((i & (1 << (j - 1))) > 0 && f[i | a[j]] > f[i] + 1) {
        f[i | a[j]] = f[i] + 1;
        ff[i | a[j]] = j;
        fff[i | a[j]] = i;
      }
  printf("%d\n", f[(1 << n) - 1]);
  for (int i = (1 << n) - 1; i; i = fff[i]) printf("%d ", ff[i]);
  return 0;
}
