#include <iostream>
#include <set>
#include <vector>
using namespace std;
int n, m;
vector<int> adj[22];
long long dp[(1 << 20)];
bool check(int mask) {
for (int i = 0; i < n; i++) {
if (mask & (1 << i)) {
for (auto j : adj[i]) {
if (mask & (1 << j)) {
return 0;
}
}
}
}
return 1;
}
int main() {
cin >> n >> m;
for (int i = 0; i < m; i++) {
int u, v;
cin >> u >> v;
u--, v--;
adj[u].push_back(v);
adj[v].push_back(u);
}
dp[0] = 1;
for (int mask = 1; mask < (1 << n); mask++) {
if (!check(mask)) continue;
dp[mask] = 1;
}
long long ans = 0;
for (int mask = 0; mask < (1 << n); mask++) {
ans += dp[mask];
}
cout << ans << endl;
}
