#include <bits/stdc++.h>
using namespace std;
int n, m;
long long dp[1 << 20][20];
int g[20][20];
int st(int s) {
  int ret = 1;
  while (s) {
    if (s % 2) return ret;
    s >>= 1, ret++;
  }
}
int main() {
  int u, v;
  long long ans = 0;
  scanf("%d %d", &n, &m);
  for (int i = 1; i <= m; i++) {
    scanf("%d %d", &u, &v);
    g[u][v] = g[v][u] = 1;
  }
  int S = (1 << n) - 1;
  for (int i = 1; i <= n; i++) dp[(1 << (i - 1))][i] = 1;
  for (int s = 1; s <= S; s++)
    for (int u = 1; u <= n; u++) {
      if (dp[s][u] == 0) continue;
      int fir = st(s);
      for (int v = fir; v <= n; v++)
        if (u != v && g[u][v]) {
          if ((s & (1 << (v - 1))) && v == fir)
            ans += dp[s][u];
          else if (!(s & (1 << (v - 1)))) {
            int ss = s | (1 << (v - 1));
            dp[ss][v] += dp[s][u];
          }
        }
    }
  ans -= m;
  ans /= 2;
  printf("%lld\n", ans);
}
