#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vvl = vector<vll>;
using pll = pair<ll,ll>;
#define f first
#define s second
#define pb push_back
#define all(v) v.begin(),v.end()
const int mod = 998244353;
int main(){
ios_base::sync_with_stdio(0);cin.tie(NULL);
ll n, m;
cin >> n >> m;
vvl g(n);
vvl cn(n, vll(n));
for(ll a,b,i = 0; i < m; ++i){
cin >> a >> b;
g[--a].pb(--b);
cn[a][b]=cn[b][a]=1;
}
vvl dp(1<<n, vll(n)), mul(1<<n, vll(n));
for(ll i = 1; i < (1<<n); ++i){
for(ll j = 0; j < n; ++j){
if(!(i & (1<<j)))continue;
ll cnt=0;
for(ll x:g[j])if(i&(1<<x))cnt++;
for(ll k = 0; k < n; ++k){
if(cn[k][j] || k<j){
dp[i][j] += dp[i^(1<<j)][k]+cnt*mul[i^(1<<j)][k];
dp[i][j]%=mod;
mul[i][j] += mul[i^(1<<j)][k];
mul[i][j]%=mod;
}
}
if((i^(1<<j))==0)mul[i][j]=1;
}
}
cout << accumulate(all(dp.back()),0ll);
}
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