#include <bits/stdc++.h>
using namespace std;
const int N = 19;
int n, m;
int E[N][N];
long long dp[N][(1 << N) + 5];
int fir[(1 << N) + 5];
int main() {
  cin >> n >> m;
  for (int i = 0; i < m; i++) {
    int a, b;
    cin >> a >> b;
    a--, b--;
    E[a][b] = E[b][a] = 1;
  }
  for (int i = 0; i < n; i++) dp[i][(1 << i)] = 1;
  for (int mask = 1; mask < (1 << n); mask++) {
    int fst = n - 1;
    while (!((mask >> fst) & 1)) fst--;
    fir[mask] = fst;
  }
  for (int mask = 1; mask < (1 << n); mask++) {
    if ((1 << fir[mask]) == mask) continue;
    for (int i = fir[mask] - 1; i >= 0; i--) {
      if (!((mask >> i) & 1)) continue;
      for (int j = 0; j < n; j++) {
        if (!((mask >> j) & 1)) continue;
        if (!E[i][j]) continue;
        dp[i][mask] += dp[j][mask ^ (1 << i)];
      }
    }
  }
  long long res = 0;
  for (int mask = 1; mask < (1 << n); mask++) {
    int pcnt = __builtin_popcount(mask);
    if (pcnt < 3) continue;
    int fst = fir[mask];
    for (int i = 0; i < n; i++) {
      if (E[fst][i]) res += dp[i][mask];
    }
  }
  cout << res / 2 << endl;
}
