#include <bits/stdc++.h>
using namespace std;
bool debug = 0;
int n, m, k;
int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0};
string direc = "RDLU";
long long ln, lk, lm;
void etp(bool f = 0) {
  puts(f ? "YES" : "NO");
  exit(0);
}
void addmod(int &x, int y, int mod = 1000000007) {
  assert(y >= 0);
  x += y;
  if (x >= mod) x -= mod;
  assert(x >= 0 && x < mod);
}
void et() {
  puts("-1");
  exit(0);
}
long long fastPow(long long x, long long y, int mod = 1000000007) {
  long long ans = 1;
  while (y > 0) {
    if (y & 1) ans = (x * ans) % mod;
    x = x * x % mod;
    y >>= 1;
  }
  return ans;
}
long long gcd1(long long x, long long y) {
  long long z = y;
  while (x % y != 0) {
    z = x % y;
    x = y;
    y = z;
  }
  return z;
}
int a[33];
int dp[(1 << 22) + 5], mn[(1 << 22) + 5], bs;
void fmain(int ID) {
  scanf("%d%d", &n, &m);
  for (int(i) = 1; (i) <= (int)(m); (i)++) {
    int u, v;
    scanf("%d%d", &u, &v);
    u--;
    v--;
    a[u] |= 1 << v;
    a[v] |= 1 << u;
  }
  bs = (1 << n) - 1;
  for (int(i) = 0; (i) < (int)(n); (i)++) dp[1 << i] = 1;
  for (int(i) = 0; (i) < (int)(n); (i)++) a[i] |= 1 << i;
  int cc = 0;
  for (int(i) = 0; (i) < (int)(n); (i)++)
    if (a[i] == (1 << n) - 1) {
      cc++;
    }
  if (cc == n) {
    puts("0");
    return;
  }
  for (int s = 0; s < (1 << n); s++)
    if (dp[s]) {
      int tmp = 0;
      for (int(j) = 0; (j) < (int)(n); (j)++)
        if (s & (1 << j)) {
          tmp |= a[j];
        }
      for (int(j) = 0; (j) < (int)(n); (j)++)
        if (tmp & (1 << j)) {
          dp[s | (1 << j)] = 1;
        }
      if (tmp == (1 << n) - 1) {
        if (__builtin_popcount(s) < __builtin_popcount(bs)) {
          bs = s;
        }
      }
    }
  printf("%d\n", __builtin_popcount(bs));
  for (int(j) = 0; (j) < (int)(n); (j)++)
    if (bs & (1 << j)) printf("%d ", j + 1);
}
int main() {
  int t = 1;
  for (int(i) = 1; (i) <= (int)(t); (i)++) {
    fmain(i);
  }
  return 0;
}
