#include<bits/stdc++.h>
using namespace std;
using ll = long long;
ll A[22][22] = {0};
int main() {
ll n, m, r,s, x, y, can, i, j, ans, t;
cin >> n >> m;
ll a[n + 2];
for (i = 0; i < n; i ++) {
a[i] = i + 1;
}
for (i = 1; i <= m; i++) {
cin >> x >> y;
A[x][y] = A[y][x] = 1;
}
ans = 0;
for (j =0; j < (1 << n); j ++) {
vector < ll >v;
for ( r = 0; r < n; r ++) {
s = (1<<r) & j;
if ( s != 0) {
v.push_back(a[r]);
}
}
can = 1;
for (i = 0; i < v.size(); i ++) {
for ( r = i + 1; r< v.size(); r ++) {
if ( A[v[i]][v[r]] == 1) {
can = 0;
}
}
}
ans += can;
}
cout << ans << endl;
}
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