#include <bits/stdc++.h>
using namespace std;
#define int long long
#define all(a) (a).begin(),(a).end()
#define rep(i, n) for(int i = 0; i < (n); i++)
signed main(){
	int n;
	cin >> n;
	int m;
	cin >> m;
	pair<int, int> p[m];
	rep(i,m){
		cin >> p[i].first >> p[i].second;
	}
	int ans = 0;
	for (int i = 0; i < (1<<n); i++){
		set<int>st;
		for (int j = 0; j < n; j++) {
			if((i>>j)%2){
				st.insert(j + 1);
			}
		}
		bool b = true;
		rep(i,m){
			if(st.find(p[i].first)==st.end() and st.find(p[i].second)==st.end()){
				b = false;
			}
		}
		if(b) ans++;
	}
	cout << ans;
	return 0;
}
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