#include using namespace std; #define ALL(x) x.begin(),x.end() #define rep(i,n) for(int i=0;i<(n);i++) #define debug(v) cout<<#v<<":";for(auto x:v){cout<bool chmax(T &a,const T &b){if(abool chmin(T &a,const T &b){if(b ostream &operator<<(ostream &os,const pair&p){ os< ostream &operator<<(ostream &os,const vector&v){ for(int i=0;i<(int)v.size();i++) os< struct ModInt{ long long x; ModInt():x(0){} ModInt(long long y):x(y>=0?y%Mod:(Mod-(-y)%Mod)%Mod){} ModInt &operator+=(const ModInt &p){ if((x+=p.x)>=Mod) x-=Mod; return *this; } ModInt &operator-=(const ModInt &p){ if((x+=Mod-p.x)>=Mod)x-=Mod; return *this; } ModInt &operator*=(const ModInt &p){ x=(int)(1ll*x*p.x%Mod); return *this; } ModInt &operator/=(const ModInt &p){ (*this)*=p.inverse(); return *this; } ModInt operator-()const{return ModInt(x);} ModInt operator+(const ModInt &p)const{return ModInt(*this)+=p;} ModInt operator-(const ModInt &p)const{return ModInt(*this)-=p;} ModInt operator*(const ModInt &p)const{return ModInt(*this)*=p;} ModInt operator/(const ModInt &p)const{return ModInt(*this)/=p;} ModInt operator==(const ModInt &p)const{return x==p.x;} ModInt operator!=(const ModInt &p)const{return x!=p.x;} ModInt inverse()const{ int a=x,b=Mod,u=1,v=0,t; while(b>0){ t=a/b; swap(a-=t*b,b);swap(u-=t*v,v); } return ModInt(u); } ModInt pow(long long n)const{ ModInt ret(1),mul(x); while(n>0){ if(n&1) ret*=mul; mul*=mul;n>>=1; } return ret; } friend ostream &operator<<(ostream &os,const ModInt &p){return os<>(istream &is,ModInt &a){long long t;is>>t;a=ModInt(t);return (is);} static int get_mod(){return Mod;} }; using mint=ModInt; template struct comcalc{ vector fact,finv,inv; comcalc():fact(MAX),finv(MAX),inv(MAX){ fact[0]=mint(1),fact[1]=mint(1),finv[0]=mint(1),finv[1]=mint(1),inv[1]=mint(1); for(int i=2;in-r) r=n-r; if(r==0) return 1; mint a=1,b=mint(fact_mod(r)).inverse(); for(int i=0;i; struct UnionFind{ vector par; vector siz; int c;//親の個数(グループ数) void init(int n){ c=n; for(int i=0;i; signed main(){ cominit F; int n,m;cin>>n>>m; mint ans=0; mint i2=mint(2).inverse(); for(int i=3;i<=n;i++){ ans+=F.com(n,i)*F.fac(i-1)*i2; } mint facsum[200000]; facsum[0]=0; for(int i=1;i<200000;i++){ facsum[i]=facsum[i-1]+F.fac(i); } int tmp=0; map vi; vector

es; rep(i,m){ int u,v;cin>>u>>v;u--,v--; es.push_back(P(u,v)); if(!vi.count(u)) vi[u]=tmp++; if(!vi.count(v)) vi[v]=tmp++; } map unko; for(int gr=1;gr<=30;gr++){ for(int rem=n;rem>=n-100;rem--){ mint g2=mint(2).pow(gr-1); mint res=0; for(int i=0;i<=rem;i++){ if(n-rem+i<3) continue; res+=F.fac(gr-1+i)*F.com(rem,i)*g2; } unko[P(gr,rem)]=res; } } int vn=vi.size(); // cout<<"shokikai "<>i)&1){ uf.unite(vi[es[i].first],vi[es[i].second]); } int gr=0,rem=n; rep(i,vn){ if(uf.root(i)==i){ if(uf.size(i)>1){ rem-=uf.size(i); gr++; } } } vector cnt(vn,0); rep(i,m)if((bit>>i)&1){ cnt[vi[es[i].first]]++; cnt[vi[es[i].second]]++; } bool f=true; rep(i,vn){ if(cnt[i]>2) f=false; } if(!f) continue; mint res; int E=__builtin_popcount(bit); int V=n-rem; if(gr==1 and V==E){ vector cnt(vn,0); rep(i,m)if((bit>>i)&1){ cnt[vi[es[i].first]]++; cnt[vi[es[i].second]]++; } bool f=true; rep(i,vn){ if(cnt[i]!=2 and cnt[i]!=0) f=false; } if(f) res=mint(1); else res=mint(0); } else if(E+gr==V) res=unko[P(gr,rem)]; else res=0; // cout<(bit)<<" "; if(__builtin_parity(bit)){ // cout<<"-"<