#include <bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int,int> pi;
#define f first
#define s second
#define FAST ios_base::sync_with_stdio(0); cin.tie(0);
#define all(x) x.begin(),x.end()
const int maxn = 25;
const int mod = 998244353;
const int INF = LLONG_MAX/2;
int n, m;
int mat[maxn][maxn];
int con[1 << 20], dp[1<<20];
int faste(int x, int exp) {
int base = x, ans = 1;
while (exp) {
if (exp & 1) ans = (ans * base) % mod;
base = (base * base) % mod;
exp >>= 1;
}
return ans;
}
int32_t main() {
FAST
cin >> n >> m;
for (int i =0;i<m;i++) {
int a,b; cin >> a >> b;
a--; b--;
mat[a][b] = mat[b][a] = 1;
}
for (int bm = 0; bm < (1 << n); bm++) {
for (int i = 0;i <n;i++) if (bm & (1 << i)) {
for (int j =0;j<n;j++) if (bm & (1 << j)) {
if (mat[i][j]) con[bm] = 1;
}
}
}
dp[0] = 1; //No. of ways to form a DAG with bm
//O(3^N)
for (int bm = 1; bm < (1 << n); bm++) {
for (int submask = bm; submask; submask = (submask - 1) & bm) {
//Fix submask to have 0 in-degree
if (con[submask]) continue;
//PIE
if (__builtin_popcount(submask) % 2) {
dp[bm] += dp[bm ^ submask];
dp[bm] %= mod;
} else {
dp[bm] = (dp[bm] - dp[bm ^ submask] + mod) % mod;
}
}
}
cout << dp[(1<<n)-1] * m % mod * faste(2, mod-2) % mod;
}
