Codechef Polo the Penguin and the Tree

The topic of general XOR is solved with trie.

The problem is the trie on the tree;

First: From Root==1, traverse the tree to get the XOR value of 1 to all nodes.

Then for each point we insert it into the binary tree.

For each point lookup, the number of binary values that are different or the maximum value is traversed sequentially.

Note: The number of edges is more than twice times, re many times.

The Find function is specific to this:

Binary value for a book: 10001000101

1#include <iostream>2#include <cstdio>3#include <algorithm>4#include <cmath>5#include <string>6#include <cstring>7#include <Set>8#include <map>9#include <stdlib.h>Ten  One #defineN 223456 A using namespacestd; - structEdge - { the   intV,w,next; - }e[n]; - intTot,nid; - intHead[n],ans[n]; + intnext[n* -][2]; - voidAddintUintVintW) + { Ae[tot].v=v; ate[tot].w=W; -e[tot].next=Head[u]; -head[u]=tot++; - } -  - voidDfsintUintFA) in { -     for(inti=head[u];i!=-1; i=e[i].next) to    { +       intv=e[i].v; -       if(V==FA)Continue; theans[v]=ans[u]^E[I].W; * DFS (v,u); $    }Panax Notoginseng } -  the voidInsertintNodeintDintval) + { A    if(d== -)return; the    intp= in-D; +    intC= (val& (1<<p))?1:0; -  $    if(next[node][c]==-1) next[node][c]=++nid; $Insert (next[node][c],d+1, Val); - } -  the intSolveintNodeintDintval) - {Wuyi   if(d== -)return 0; the   intp= in-D; -   intC= (val& (1<<p))?0:1; Wu  -   if(next[node][c]!=-1) About   return(1<<p) +solve (next[node][c],d+1, Val); $  -   returnSolve (next[node][!c],d+1, Val); - } -  A intMain () + { the   intT; -scanf"%d",&T); $    while(t--) the   { the      intN; thescanf"%d",&n); thememset (head,-1,sizeof(head)); -memset (next,-1,sizeof(next)); inmemset (ans,0,sizeof(ans)); theTot=nid=0; the       for(intI=1; i<n;i++) About      { the         intu,v,w; thescanf"%d%d%d",&u,&v,&W); the Add (u,v,w); + Add (v,u,w); -      } the BayiDfs1,-1); the       for(intI=1; i<=n;i++) Insert (0,0, Ans[i]); the      inttmp=0; -  -       for(intI=1; i<=n;i++) theTmp=max (Tmp,solve (0,0, Ans[i])); theprintf"%d\n", TMP); the      } the      return 0; -}

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Let's just Judge 01110111010.

There is no so that the maximum value can be reached

Codechef Polo the Penguin and the Tree