#include <bits/stdc++.h>
using namespace std;
template <typename T, typename U>
std::istream& operator>>(std::istream& i, pair<T, U>& p) {
  i >> p.first >> p.second;
  return i;
}
template <typename T>
std::istream& operator>>(std::istream& i, vector<T>& t) {
  for (auto& v : t) {
    i >> v;
  }
  return i;
}
template <typename T>
std::ostream& operator<<(std::ostream& o, const vector<T>& t) {
  for (size_t i = 0; i < t.size(); ++i) {
    o << t[i] << " \n"[i == t.size() - 1];
  }
  return o;
}
template <typename T>
using minheap = priority_queue<T, vector<T>, greater<T>>;
template <typename T>
using maxheap = priority_queue<T, vector<T>, less<T>>;
auto fraclt = [](const std::pair<int, int>& a, const std::pair<int, int>& b) {
  return (long long)a.first * b.second < (long long)b.first * a.second;
};
struct cmpfrac {
  bool operator()(const std::pair<int, int>& a,
                  const std::pair<int, int>& b) const {
    return (long long)a.first * b.second < (long long)b.first * a.second;
  }
};
template <typename T>
bool in(T a, T b, T c) {
  return a <= b && b < c;
}
unsigned int logceil(long long first) {
  unsigned int b = 0;
  while (first) {
    first >>= 1;
    ++b;
  }
  return b;
}
namespace std {
template <typename T, typename U>
struct hash<pair<T, U>> {
  hash<T> t;
  hash<U> u;
  size_t operator()(const pair<T, U>& p) const {
    return t(p.first) ^ (u(p.second) << 7);
  }
};
}  // namespace std
template <typename T, typename F>
T bsh(T l, T h, const F& f) {
  T r = -1, m;
  while (l <= h) {
    m = (l + h) / 2;
    if (f(m)) {
      l = m + 1;
      r = m;
    } else {
      h = m - 1;
    }
  }
  return r;
}
template <typename F>
double bsh(double l, double h, const F& f, double p = 1e-9) {
  unsigned int r = 3 + (unsigned int)log2((h - l) / p);
  while (r--) {
    double m = (l + h) / 2;
    if (f(m)) {
      l = m;
    } else {
      h = m;
    }
  }
  return (l + h) / 2;
}
template <typename T, typename F>
T bsl(T l, T h, const F& f) {
  T r = -1, m;
  while (l <= h) {
    m = (l + h) / 2;
    if (f(m)) {
      h = m - 1;
      r = m;
    } else {
      l = m + 1;
    }
  }
  return r;
}
template <typename F>
double bsl(double l, double h, const F& f, double p = 1e-9) {
  unsigned int r = 3 + (unsigned int)log2((h - l) / p);
  while (r--) {
    double m = (l + h) / 2;
    if (f(m)) {
      h = m;
    } else {
      l = m;
    }
  }
  return (l + h) / 2;
}
template <typename T>
T gcd(T a, T b) {
  if (a < b) swap(a, b);
  return b ? gcd(b, a % b) : a;
}
template <typename T>
class vector2 : public vector<vector<T>> {
 public:
  vector2() {}
  vector2(size_t a, size_t b, T t = T())
      : vector<vector<T>>(a, vector<T>(b, t)) {}
};
template <typename T>
class vector3 : public vector<vector2<T>> {
 public:
  vector3() {}
  vector3(size_t a, size_t b, size_t c, T t = T())
      : vector<vector2<T>>(a, vector2<T>(b, c, t)) {}
};
template <typename T>
class vector4 : public vector<vector3<T>> {
 public:
  vector4() {}
  vector4(size_t a, size_t b, size_t c, size_t d, T t = T())
      : vector<vector3<T>>(a, vector3<T>(b, c, d, t)) {}
};
template <typename T>
class vector5 : public vector<vector4<T>> {
 public:
  vector5() {}
  vector5(size_t a, size_t b, size_t c, size_t d, size_t e, T t = T())
      : vector<vector4<T>>(a, vector4<T>(b, c, d, e, t)) {}
};
template <typename T>
struct bounded_priority_queue {
  inline bounded_priority_queue(unsigned int X) : A(X), B(0) {}
  inline void push(unsigned int L, T V) {
    B = max(B, L);
    A[L].push(V);
  }
  inline const T& top() const { return A[B].front(); }
  inline void pop() {
    A[B].pop();
    while (B > 0 && A[B].empty()) --B;
  }
  inline bool empty() const { return A[B].empty(); }
  inline void clear() {
    B = 0;
    for (auto& a : A) a = queue<T>();
  }

 private:
  vector<queue<T>> A;
  unsigned int B;
};
class TaskC {
 public:
  int N, M;
  vector<int> E;
  void solve(istream& cin, ostream& cout) {
    cin >> N >> M;
    if (M == N * (N - 1) / 2) {
      cout << "0\n";
      return;
    }
    E = vector<int>(N, 0);
    for (int i = 0; i < M; ++i) {
      int a, b;
      cin >> a >> b;
      --a;
      --b;
      E[a] |= (1 << b);
      E[b] |= (1 << a);
    }
    vector<int> D(1 << N, 0);
    for (int i = 0; i < N; ++i) {
      E[i] |= (1 << i);
      D[1 << i] = E[i];
    }
    int all = (1 << N) - 1;
    int b = all, c = N;
    for (int i = 1; i < (1 << N); ++i) {
      if (D[i] == all) {
        int e = __builtin_popcount(i);
        if (e < c) {
          b = i;
          c = e;
        }
      } else if (D[i] != 0) {
        for (int j = 0; j < N; ++j) {
          if ((D[i] & (1 << j)) == (1 << j) && (i & (1 << j)) == 0) {
            D[i | (1 << j)] = D[i] | E[j];
          }
        }
      }
    }
    cout << c << endl;
    for (int i = 0; i < N; ++i) {
      if ((b & (1 << i)) == (1 << i)) {
        cout << i + 1 << ' ';
      }
    }
    cout << endl;
  }
};
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  TaskC solver;
  std::istream& in(std::cin);
  std::ostream& out(std::cout);
  solver.solve(in, out);
  return 0;
}
