#include<bits/stdc++.h>
using namespace std;
int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	int n, m;
	cin >> n >> m;
	bool c[n + 1][n + 1] {};
	for(int i = 0; i < m; i++) {
		int a, b;
		cin >> a >> b;
		c[a][b] = c[b][a] = 1;
	}
	int cnt = 0;
	for(int i = 0; i < (1 << n); i++) {
		vector<int> v;
		bool ok = 1;
		for(int j = 0; j < n; j++) {
			if((i >> j) % 2 == 1) v.push_back(j + 1);
		}
		int sz = v.size();
		for(int j = 0; j < sz; j++) {
			for(int k = j + 1; k < sz; k++) {
				if(c[v[j]][v[k]]) ok = 0;
			}
		}
		cnt += (ok ? 1 : 0);
	}
	cout << cnt << '\n';
	return 0;
}
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