#include <bits/stdc++.h>
using namespace std;
template <class C>
void mini(C& a4, C b4) {
  a4 = min(a4, b4);
}
template <class C>
void maxi(C& a4, C b4) {
  a4 = max(a4, b4);
}
template <typename T1, typename T2>
ostream& operator<<(ostream& out, pair<T1, T2> pair) {
  out << "(" << pair.first << ", " << pair.second << ")";
  return out;
}
const int N = 19;
const int K = 1 << 19;
bool edge[N][N];
long long t[K][N];
int main() {
  ios_base::sync_with_stdio(false);
  cout << fixed << setprecision(10);
  int n, m;
  cin >> n >> m;
  for (int i = 0; i < (n); ++i)
    for (int j = 0; j < (n); ++j) edge[i][j] = false;
  for (int i = 0; i < (m); ++i) {
    int x, y;
    cin >> x >> y;
    --x;
    --y;
    edge[x][y] = true;
    edge[y][x] = true;
  }
  if (n == 1) {
    printf("0\n");
    return 0;
  }
  if (n == 2) {
    printf("0\n");
    return 0;
  }
  long long sum = 0;
  for (int s = 0; s < (n); ++s) {
    int k = 1 << s;
    for (int kk = 0; kk < (k << 1); ++kk)
      for (int i = 0; i < (s + 1); ++i) t[kk][i] = 0;
    t[0][s] = 1;
    for (int kk = 0; kk < (k); ++kk) {
      for (int i = 0; i < (s); ++i)
        if (kk & (1 << i)) {
          for (int j = 0; j < (s + 1); ++j)
            if (edge[i][j]) {
              t[kk][i] += t[kk - (1 << i)][j];
            }
          if ((kk != (1 << i)) && (edge[i][s])) {
            sum += t[kk][i];
          }
        }
    }
  }
  cout << sum / 2 << endl;
  return 0;
}
