#include <bits/stdc++.h>
using namespace std;
int ad[19], u, v, n, m;
unsigned long long dp[1 << 19][19], ans;
int main() {
  cin >> n >> m;
  for (int i = 0; i < m; ++i) {
    cin >> u >> v;
    --u, --v;
    ad[u] |= 1 << v;
    ad[v] |= 1 << u;
  }
  for (int i = 0; i < n; ++i) dp[1 << i][i] = 1;
  for (int msk = 1; msk < (1 << n); ++msk) {
    int idx = __builtin_ctz(msk);
    for (int i = idx + 1; i < n; ++i) {
      if ((msk & (1 << i)) == 0) continue;
      int tmsk = msk & ad[i];
      for (int j = 0; j < n; ++j) {
        if (i == j || ((1 << j) & tmsk) == 0) continue;
        dp[msk][i] += dp[msk ^ (1 << i)][j];
      }
    }
    if (__builtin_popcount(msk) > 2) {
      int tmsk = ad[idx] & msk;
      for (int j = idx + 1; j < n; ++j) {
        if (tmsk & (1 << j)) ans += dp[msk][j];
      }
    }
  }
  cout << ans / 2 << endl;
  return 0;
}
