#include <bits/stdc++.h>
using namespace std;
int n, s;
int gr[20][20];
long long dp[1 << 19][20];
long long f(int bt, int i) {
  long long &res = dp[bt][i];
  if (res != -1) return res;
  res = 0;
  for (int j = s; j < n; j++) {
    if (gr[i][j] && !(bt & (1 << j))) res += f(bt + (1 << j), j);
    if (gr[i][j] && i != s && j == s && bt > (1 << i) + (1 << s)) res++;
  }
  return res;
}
int main() {
  int a, b, m;
  cin >> n >> m;
  for (int i = 0; i < m; i++) {
    cin >> a >> b;
    gr[a - 1][b - 1] = gr[b - 1][a - 1] = 1;
  }
  long long ans = 0;
  for (int i = 0; i < n; i++) {
    memset(dp, -1, sizeof dp);
    s = i;
    ans += f(1 << i, i) / 2;
  }
  cout << ans << endl;
  return 0;
}
