#include <bits/stdc++.h>
#pragma GCC optimize("O3")
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
const ll mod=998244353,inv2=499122177;
int n,m,bits[25],lg,cmask[25];
int dp[(1<<18)+5];
int B[25];
bool isthere[1000006];
ll gethash(ll x, ll y)
{
ll rez=(x<<18);
rez+=y;
return rez;
}
bool good[(1<<18)+5],edge[25][25];
int bit[(1<<18)+5];
int main()
{
cin>>n>>m;
for(int i=1;i<=m;i++)
{
int a,b;
cin>>a>>b;
cmask[a]+=(1<<(b-1));
cmask[b]+=(1<<(a-1));
a--;
b--;
edge[a][b]=edge[b][a]=1;
}
for(int mask=0;mask<(1<<n);mask++)
{
for(int a=0;a<n;a++)
if((mask>>a)&1)
for(int b=0;b<n;b++)
if((mask>>b)&1)
good[mask]|=edge[a][b];
good[mask]= !good[mask];
if(mask==0)
bit[mask]=-1;
else
{
int lsb=(mask&(-mask));
bit[mask]=bit[mask^lsb]*(-1);
}
}
for(int mask=0;mask<(1<<n);mask++)
{
if(good[mask])
{
dp[mask]=1;
continue;
}
for(int submask=mask;submask>0;submask=(submask-1)&mask)
if(good[submask]&&submask!=mask)
dp[mask]=(dp[mask]+bit[submask]*dp[mask^submask]+mod)%mod;
}
ll ans=dp[(1<<n)-1];
ans=(ans*m)%mod;
ans=(ans*inv2)%mod;
cout<<ans;
return 0;
}
