Bzoj 4326 tree chain split + dichotomy + differential + memory

I didn't have a tree chain Noip last year!

Or a group of UOJ data cards.

The idea of difference is still very divine!

1#include <iostream>2#include <cstring>3#include <cstdio>4#include <algorithm>5#include <ctime>6#include <cstdlib>7 using namespacestd;8 Const intmaxn=300100;9 Const intinf=0x3f3f3f3f;Ten intN,m,u,v,w,cnt,tot,maxlen,minlen,minw,maxw,ans; One intHEAD[MAXN],DEP[MAXN],SIZ[MAXN],FATHER[MAXN],W[MAXN],P[MAXN],Q[MAXN],DIS[MAXN],LEN[MAXN],C[MAXN],TOP[MAXN], Memory[maxn],root; A structedge{intTo,next,w;} edge[maxn<<1]; -InlinevoidGet_int (int&x) - { thex=0;CharCh=getchar ();intf=1; -      while(ch<'0'|| Ch>'9') {if(ch=='-') f=-1; Ch=GetChar ();} -      while(ch>='0'&& ch<='9') {x=x*Ten+ch-'0'; Ch=getchar ();} x*=F; - } +InlinevoidPut_int (intx) - { +     Charch[ -];inttop=0; A     if(x==0) ch[++top]='0'; at      while(x) ch[++top]=x%Ten+'0', x/=Ten; -      while(top) Putchar (ch[top--]); Putchar ('\ n'); - } -InlineintMax (intXintY) {returnX>y?x:y;} -InlineintMin (intXintY) {returnX>y?y:x;} -InlinevoidADD (intUintVintW) in{edge[cnt].to=v;edge[cnt].next=head[u];edge[cnt].w=w;head[u]=cnt++;} - //============================================== to voidDFS1 (intUintFA) + { -siz[u]=1; the      for(inti=head[u];i!=-1; i=edge[i].next) *         if(edge[i].to!=FA) $         {Panax Notoginsengdep[edge[i].to]=dep[u]+1; -father[edge[i].to]=u; thedis[edge[i].to]=dis[u]+EDGE[I].W; +w[edge[i].to]=EDGE[I].W; A DFS1 (edge[i].to,u); thesiz[u]+=siz[edge[i].to]; +         } - } $ voidDFS2 (intUintChainintFA) $ { -Top[u]=chain;intk=0; -      for(inti=head[u];i!=-1; i=edge[i].next) the         if(Edge[i].to!=fa && (siz[edge[i].to]>siz[k] | | k==0)) k=edge[i].to; -     if(k==0)return;Wuyi DFS2 (k,chain,u); the      for(inti=head[u];i!=-1; i=edge[i].next) -         if(Edge[i].to!=fa && k!=edge[i].to) DFS2 (edge[i].to,edge[i].to,u); Wu } -InlineintLCA (intUintv) About { $      while(true) -     { -         if(Top[u]==top[v])returnDEP[U]&GT;DEP[V]?v:u; -         if(Dep[top[u]]>dep[top[v]]) u=father[top[u];Elsev=Father[top[v]]; A     } + } the intGet (intUintf) - { $      for(inti=head[u];i!=-1; i=edge[i].next) the         if(f!=edge[i].to) thec[u]+=Get (edge[i].to,u); the     if(C[u]==tot) minlen=Max (Minlen,w[u]); the     returnC[u]; - } inInlineBOOLCheck (intt) the { themaxlen=minlen=tot=0; AboutMemset (c,0,sizeof(c)); the      for(intI=1; i<=m;i++) the         if(len[i]>t) the         { +c[p[i]]++,c[q[i]]++; -C[lca (P[i],q[i])]-=2; themaxlen=Max (Maxlen,len[i]);Bayitot++; the         } the     if(Memory[tot]) -     { -         if(memory[tot]<=t)return true; the         return false; the     } the Get (root,root); theMemory[tot]= (maxlen-Minlen); -     if(memory[tot]<=t)return true; the     return false; the } the intMain ()94 { theSrand (Time (0)); the get_int (n), Get_int (m); thememset (head,-1,sizeof(head)); minw=Inf;98      for(intI=1; i<n;i++) About     { - get_int (U), Get_int (v), Get_int (w);101 Add (u,v,w), add (v,u,w);102minw=Min (minw,w);103     }104      for(intI=1; i<=m;i++) Get_int (P[i]), Get_int (Q[i]); theRoot=rand ()%n+1;106Father[root]=root; dep[root]=1; dis[root]=0;107 DFS1 (root,root);108 DFS2 (root,root,root);109memset (Memory,0,sizeof(Memory)); the      for(intI=1; i<=m;i++) len[i]=dis[p[i]]+dis[q[i]]-2*dis[lca (P[i],q[i])],maxw=Max (Maxw,len[i]);111     intL=minw,r=Maxw; the      while(l<=R)113     { the         intMid= (l+r) >>1; the         if(Check (mid)) ans=mid,r=mid-1;ElseL=mid+1; the         117     }118 Put_int (Ans);119     return 0; -}

C + +

Bzoj 4326 tree chain split + dichotomy + differential + memory