#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef double db;
typedef pair <int, int> pin;

#ifndef ONLINE_JUDGE
bool MEMORY_ST;
#endif

const int N = 19;
const int M = 1 << 19;
const ll P = 998244353LL;

int n, m;
bool e[N][N];
ll f[M][N];

namespace Fread {
    const int L = 1 << 15;
    
    char buffer[L], *S, *T;
    
    inline char Getchar() {
        if(S == T) {
            T = (S = buffer) + fread(buffer, 1, L, stdin);
            if(S == T) return EOF;
        }
        return *S++;
    }
    
    template <class T> 
    inline void read(T &X) {
        char ch; T op = 1;
        for(ch = Getchar(); ch > '9' || ch < '0'; ch = Getchar())
            if(ch == '-') op = -1;
        for(X = 0; ch >= '0' && ch <= '9'; ch = Getchar()) 
            X = (X << 1) + (X << 3) + ch - '0'; 
        X *= op;
    }
    
} using Fread::read;  

inline int lowbit(int s) {
    return s & (-s);
}

#ifndef ONLINE_JUDGE
bool MEMORY_ED;
#endif

int main() {
#ifndef ONLINE_JUDGE
    freopen("sample.in", "r", stdin);
    clock_t st_clock = clock();
#endif

    read(n), read(m);
    for (int x, y, i = 1; i <= m; i++) {
        read(x), read(y);
        x--, y--;
        e[x][y] = e[y][x] = 1;
    }
    ll ans = 0;
    for (int s = 1; s < (1 << n); s++) {
        int cnt = __builtin_popcount(s);
        for (int i = 0; i < n; i++) {
            if (!(s & (1 << i))) continue;
            if (cnt == 1) f[s][i] = 1;
            int k = __builtin_ctz(lowbit(s));
            for (int j = 0; j < n; j++) {
                if (s & (1 << j)) continue;
                if (j <= k) continue;
                if (!e[i][j]) continue;
                f[s | (1 << j)][j] += f[s][i];
            }
            if (e[i][k]) ans += f[s][i];
        }
    }
    ans -= m;
    ans >>= 1;
    printf("%lld\n", ans);

#ifndef ONLINE_JUDGE
    clock_t ed_clock = clock();
    printf("time = %f ms\n", (double)(ed_clock - st_clock) / CLOCKS_PER_SEC * 1000);
    printf("memory = %.2f MB\n", (&MEMORY_ED - &MEMORY_ST) / 1024.0 / 1024.0);
#endif
    return 0;
}