// Source: https://usaco.guide/general/io
#include <bits/stdc++.h>
using namespace std;
#define LL long long
#define MODULE 998244353
int N,M;
int adj[20];
//map<int,int> ni;
int sign[1<<18];
int popc[1<<18];
bool indp[1<<18];
LL dp[1<<18];
LL exp(LL a, LL b) {
if (a==0) return 0;
if (b == 0) return 1;
LL ret = exp(a, b/2);
ret = ret * ret;
ret %= MODULE;
if (b % 2) {
ret *= a;
ret %= MODULE;
}
return ret;
}
LL inv(LL x) {
return exp(x, MODULE-2);
}
int main() {
cin >> N >> M;
for (int i = 0; i < M; i++) {
int a,b; cin >> a >> b; a--;b--;
adj[a] |= (1 << b);
adj[b] |= (1<<a);
}
/*cout << "adj: " << endl;
for (int i = 0; i < N; i++) {
cout << adj[i] << endl;
}*/
for (int i = 0; i < (1<<N); i++) {
popc[i] = popc[i>>1] + (i&1);
sign[i] = (popc[i] % 2) ? (1) : (-1);
}
indp[0] = true;
for (int i = 1; i < (1<<N); i++) {
for (int j = 0; j < N; j++) {
if (!(i&(1<<j))) continue;
if (!indp[i&~(1<<j)]) continue;
if ((adj[j]&(i&~(1<<j))) == 0) {
indp[i] = true;
}
}
/*if (indp[i]) {
cout << "indp: " << i << endl;
}*/
}
dp[0] = 1;
for (int i = 1; i < (1<<N); i++) {
for (int j = i; j; j=(j-1)&i) {
if (!indp[j]) continue;
if (dp[i&~j]==0) continue;
dp[i]+=dp[i&~j]*sign[j];
dp[i]%=MODULE;
dp[i]=(dp[i]+MODULE)%MODULE;
}
//cout << "dp["<<i<<"] = " << dp[i] << endl;
}
LL res = dp[(1<<N)-1];
//cout << res << endl;
res *= M;
res %= MODULE;
res *= inv(2);
res %= MODULE;
cout << res << endl;
}
