#include using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) //------------------------------------------------------- int N,M; int A[15],B[15]; ll dp[1<<15]; const ll mo=998244353; template class UF { public: vector par,rank,cnt; UF() {par=rank=vector(um,0); cnt=vector(um,1); for(int i=0;irank[y]) return par[x]=y; rank[x]+=rank[x]==rank[y]; return par[y]=x; } }; const int NUM_=400001; static ll fact[NUM_+1],factr[NUM_+1],inv[NUM_+1]; ll comb(ll N_, ll C_) { if(C_<0 || C_>N_) return 0; return factr[C_]*fact[N_]%mo*factr[N_-C_]%mo; } map memo[16]; ll pat(int space,int N) { if(memo[space].count(N)) return memo[space][N]; ll ret=0; int sel; if(N!=::N-2) { for(sel=0;sel<=N;sel++) { ll pat=comb(N,sel)*fact[sel]%mo*comb(sel+space-1,space-1)%mo; ret+=pat; } ret%=mo; ret*=fact[space-1]*(1<<(space-1))%mo; } else { for(sel=1;sel<=N;sel++) { ll pat=comb(N,sel)*fact[sel]%mo; ret+=pat; } } return memo[space][N]=ret%mo; } void solve() { int i,j,k,l,r,x,y; string s; inv[1]=fact[0]=factr[0]=1; for (int i=2;i<=NUM_;++i) inv[i] = inv[mo % i] * (mo - mo / i) % mo; for (int i=1;i<=NUM_;++i) fact[i]=fact[i-1]*i%mo, factr[i]=factr[i-1]*inv[i]%mo; cin>>N>>M; vector V; FOR(i,M) { cin>>A[i]>>B[i]; V.push_back(A[i]); V.push_back(B[i]); } sort(ALL(V)); FOR(i,M) { A[i]=lower_bound(ALL(V),A[i])-V.begin(); B[i]=lower_bound(ALL(V),B[i])-V.begin(); } int mask; ll ret=0; // no selected edge for(j=3;j<=N;j++) ret+=comb(N,j)*fact[j-1]%mo*((mo+1)/2)%mo; for(mask=1;mask<1< uf; map P; int c=0; FOR(i,M) if(mask&(1<