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| #include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define maxn 5005
#define put() putchar('\n')
#define Tp template<typename Ty>
#define Ts template<typename Ty,typename... Ar>
using namespace std;
void read(int &x){
int f=1;x=0;char c=getchar();
while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();}
while (c>='0'&&c<='9') {x=x*10+c-'0';c=getchar();}
x*=f;
}
namespace Debug{
Tp void _debug(char* f,Ty t){cerr<<f<<'='<<t<<endl;}
Ts void _debug(char* f,Ty x,Ar... y){while(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
Tp ostream& operator<<(ostream& os,vector<Ty>& V){os<<"[";for(auto& vv:V) os<<vv<<",";os<<"]";return os;}
#define gdb(...) _debug((char*)#__VA_ARGS__,__VA_ARGS__)
}using namespace Debug;
#define fi first
#define se second
#define mk make_pair
const int mod=998244353;
int power(ll x,int y=mod-2) {
ll sum=1;
while (y) {
if (y&1) sum=sum*x%mod;
x=x*x%mod;y>>=1;
}
return sum;
}
int h[maxn],head=1;
struct yyy {
int to,z,flag;
void add(int x,int y) {
to=y;z=h[x];h[x]=head;
}
}a[maxn*4];
unsigned pw[maxn*maxn];
vector<int>to[maxn];
int times,tot,n,m,eccnum;
int dfn[maxn],low[maxn],stac[maxn],vis[maxn],ecc[maxn];
void tarjan(int x,int pre) {
int i;
dfn[x]=low[x]=++times;stac[++tot]=x;vis[x]=1;
for (i=h[x];i;i=a[i].z) if ((i^1)^pre) {
if (!dfn[a[i].to]) {
tarjan(a[i].to,i);
low[x]=min(low[x],low[a[i].to]);
}
else if (vis[a[i].to]) low[x]=min(low[x],dfn[a[i].to]);
}
if (dfn[x]==low[x]) {
a[i].flag=a[i^1].flag=1;
++eccnum;
while (tot) {
ecc[stac[tot]]=eccnum;
vis[stac[tot]]=0;
if (stac[tot--]==x) break;
}
}
}
int f[maxn][maxn],g[maxn],siz[maxn],v[maxn];
void add(int &x,int y) {x=(x+y)%mod;}
void dfs(int x,int pre) {
int i,j;
if (v[x]) {exit(0);}
v[x]=1;
f[x][siz[x]]=1;
for (auto y:to[x]) if (y^pre) {
dfs(y,x);
for (i=1;i<=siz[x];i++) {
for (j=1;j<=siz[y];j++){
add(g[i+j],1ll*f[x][i]*f[y][j]%mod);
add(g[i],mod-1ll*f[x][i]*f[y][j]%mod*pw[j*(j-1)/2]*2%mod);
}
}
siz[x]+=siz[y];
for (i=0;i<=siz[x];i++) f[x][i]=g[i],g[i]=0;
}
}
int ans;
signed main(void){
int i,j,x,y;
read(n);read(m);
for (i=1;i<=m;i++) {
read(x);read(y);
a[++head].add(x,y);
a[++head].add(y,x);
}
for (i=1;i<=n;i++) if (!dfn[i]) {
tarjan(i,0);
if (tot) {
++eccnum;
while (tot) {
ecc[stac[tot]]=eccnum;
vis[stac[tot]]=0;
tot--;
}
}
}
for (i=1;i<=n;i++) {
siz[ecc[i]]++;
for (j=h[i];j;j=a[j].z)
if (ecc[i]^ecc[a[j].to]) {
to[ecc[i]].push_back(ecc[a[j].to]);
}
}
int N=n*n;
for (pw[0]=1,i=1;i<=N;i++) pw[i]=1ll*pw[i-1]*2%mod;
dfs(1,0);
for (i=1;i<=n;i++) add(ans,1ll*f[1][i]*pw[i*(i-1)/2]%mod);
printf("%d",1ll*ans*power(pw[m])%mod);
return 0;
}
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