結果
問題 | No.827 総神童数 |
ユーザー |
![]() |
提出日時 | 2024-04-08 07:39:54 |
言語 | PyPy3 (7.3.15) |
結果 |
AC
|
実行時間 | 474 ms / 2,000 ms |
コード長 | 9,064 bytes |
コンパイル時間 | 351 ms |
コンパイル使用メモリ | 82,304 KB |
実行使用メモリ | 139,824 KB |
最終ジャッジ日時 | 2024-10-01 04:59:14 |
合計ジャッジ時間 | 12,034 ms |
ジャッジサーバーID (参考情報) |
judge1 / judge3 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 36 |
ソースコード
class Graph:def __init__(self,V,edges=None,graph=None,directed=False,weighted=False,inf=float("inf")):self.V=Vself.directed=directedself.weighted=weightedself.inf=infif graph!=None:self.graph=graph"""self.edges=[]for i in range(self.V):if self.weighted:for j,d in self.graph[i]:if self.directed or not self.directed and i<=j:self.edges.append((i,j,d))else:for j in self.graph[i]:if self.directed or not self.directed and i<=j:self.edges.append((i,j))"""else:self.edges=edgesself.graph=[[] for i in range(self.V)]if weighted:for i,j,d in self.edges:self.graph[i].append((j,d))if not self.directed:self.graph[j].append((i,d))else:for i,j in self.edges:self.graph[i].append(j)if not self.directed:self.graph[j].append(i)def SIV_DFS(self,s,bipartite_graph=False,cycle_detection=False,directed_acyclic=False,euler_tour=False,linked_components=False,lowlink=False,parents=False,postorder=False,preorder=False,subtree_size=False,topological_sort=False,unweighted_dist=False,weighted_dist=False):seen=[False]*self.Vfinished=[False]*self.Vif directed_acyclic or cycle_detection or topological_sort:dag=Trueif euler_tour:et=[]if linked_components:lc=[]if lowlink:order=[None]*self.Vll=[None]*self.Vidx=0if parents or cycle_detection or lowlink or subtree_size:ps=[None]*self.Vif postorder or topological_sort:post=[]if preorder:pre=[]if subtree_size:ss=[1]*self.Vif unweighted_dist or bipartite_graph:uwd=[self.inf]*self.Vuwd[s]=0if weighted_dist:wd=[self.inf]*self.Vwd[s]=0stack=[(s,0)] if self.weighted else [s]while stack:if self.weighted:x,d=stack.pop()else:x=stack.pop()if not seen[x]:seen[x]=Truestack.append((x,d) if self.weighted else x)if euler_tour:et.append(x)if linked_components:lc.append(x)if lowlink:order[x]=idxll[x]=idxidx+=1if preorder:pre.append(x)for y in self.graph[x]:if self.weighted:y,d=yif not seen[y]:stack.append((y,d) if self.weighted else y)if parents or cycle_detection or lowlink or subtree_size:ps[y]=xif unweighted_dist or bipartite_graph:uwd[y]=uwd[x]+1if weighted_dist:wd[y]=wd[x]+delif not finished[y]:if (directed_acyclic or cycle_detection or topological_sort) and dag:dag=Falseif cycle_detection:cd=(y,x)elif not finished[x]:finished[x]=Trueif euler_tour:et.append(~x)if lowlink:bl=Truefor y in self.graph[x]:if self.weighted:y,d=yif ps[x]==y and bl:bl=Falsecontinuell[x]=min(ll[x],order[y])if x!=s:ll[ps[x]]=min(ll[ps[x]],ll[x])if postorder or topological_sort:post.append(x)if subtree_size:for y in self.graph[x]:if self.weighted:y,d=yif y==ps[x]:continuess[x]+=ss[y]if bipartite_graph:bg=[[],[]]for tpl in self.edges:x,y=tpl[:2] if self.weighted else tplif uwd[x]==self.inf or uwd[y]==self.inf:continueif not uwd[x]%2^uwd[y]%2:bg=Falsebreakelse:for x in range(self.V):if uwd[x]==self.inf:continuebg[uwd[x]%2].append(x)retu=()if bipartite_graph:retu+=(bg,)if cycle_detection:if dag:cd=[]else:y,x=cdcd=self.Route_Restoration(y,x,ps)retu+=(cd,)if directed_acyclic:retu+=(dag,)if euler_tour:retu+=(et,)if linked_components:retu+=(lc,)if lowlink:retu=(ll,)if parents:retu+=(ps,)if postorder:retu+=(post,)if preorder:retu+=(pre,)if subtree_size:retu+=(ss,)if topological_sort:if dag:tp_sort=post[::-1]else:tp_sort=[]retu+=(tp_sort,)if unweighted_dist:retu+=(uwd,)if weighted_dist:retu+=(wd,)if len(retu)==1:retu=retu[0]return retudef Extended_Euclid(n,m):stack=[]while m:stack.append((n,m))n,m=m,n%mif n>=0:x,y=1,0else:x,y=-1,0for i in range(len(stack)-1,-1,-1):n,m=stack[i]x,y=y,x-(n//m)*yreturn x,yclass MOD:def __init__(self,p,e=None):self.p=pself.e=eif self.e==None:self.mod=self.pelse:self.mod=self.p**self.edef Pow(self,a,n):a%=self.modif n>=0:return pow(a,n,self.mod)else:#assert math.gcd(a,self.mod)==1x=Extended_Euclid(a,self.mod)[0]return pow(x,-n,self.mod)def Build_Fact(self,N):assert N>=0self.factorial=[1]if self.e==None:for i in range(1,N+1):self.factorial.append(self.factorial[-1]*i%self.mod)else:self.cnt=[0]*(N+1)for i in range(1,N+1):self.cnt[i]=self.cnt[i-1]ii=iwhile ii%self.p==0:ii//=self.pself.cnt[i]+=1self.factorial.append(self.factorial[-1]*ii%self.mod)self.factorial_inve=[None]*(N+1)self.factorial_inve[-1]=self.Pow(self.factorial[-1],-1)for i in range(N-1,-1,-1):ii=i+1while ii%self.p==0:ii//=self.pself.factorial_inve[i]=(self.factorial_inve[i+1]*ii)%self.moddef Build_Inverse(self,N):self.inverse=[None]*(N+1)assert self.p>Nself.inverse[1]=1for n in range(2,N+1):if n%self.p==0:continuea,b=divmod(self.mod,n)self.inverse[n]=(-a*self.inverse[b])%self.moddef Inverse(self,n):return self.inverse[n]def Fact(self,N):if N<0:return 0retu=self.factorial[N]if self.e!=None and self.cnt[N]:retu*=pow(self.p,self.cnt[N],self.mod)%self.modretu%=self.modreturn retudef Fact_Inve(self,N):if self.e!=None and self.cnt[N]:return Nonereturn self.factorial_inve[N]def Comb(self,N,K,divisible_count=False):if K<0 or K>N:return 0retu=self.factorial[N]*self.factorial_inve[K]%self.mod*self.factorial_inve[N-K]%self.modif self.e!=None:cnt=self.cnt[N]-self.cnt[N-K]-self.cnt[K]if divisible_count:return retu,cntelse:retu*=pow(self.p,cnt,self.mod)retu%=self.modreturn retuN=int(input())edges=[]for i in range(N-1):u,v=map(int,input().split())u-=1;v-=1edges.append((u,v))G=Graph(N,edges=edges)dist=G.SIV_DFS(0,unweighted_dist=True)mod=10**9+7MD=MOD(mod)MD.Build_Fact(N)MD.Build_Inverse(N)ans=0for x in range(N):ans+=MD.Inverse(dist[x]+1)ans%=modans*=MD.Fact(N)ans%=modprint(ans)