LCA of POJ 1330 Nearest Common Ancestors multiplication algorithm

POJ 1330 Nearest Common Ancestors

Test instructions: Nude topic of the recent public ancestor

Idea: LCA and St We are already familiar with, but here f[i][j] have similar but different meanings. F[I][J] Represents the number of 2j fathers of the I node

This code is not mine, transfer from Bingbin Blog

1 /* ***********************************************2 Author:kuangbin3 Created time:2013-9-5 9:45:174 File NAME:F:\2013ACM exercises \ Thematic Learning \lca\poj1330_3.cpp5 ************************************************ */6 7#include <stdio.h>8#include <string.h>9#include <iostream>Ten#include <algorithm> One#include <vector> A#include <queue> -#include <Set> -#include <map> the#include <string> -#include <math.h> -#include <stdlib.h> -#include <time.h> + using namespacestd; - /* + * POJ 1330 A * LCA Online algorithm at */ - Const intMAXN =10010; - Const intDEG = -; -  - structEdge - { in     intto, next; -}EDGE[MAXN *2]; to intHEAD[MAXN], tot; + voidAddedge (intUintv) - { theEdge[tot].to =v; *Edge[tot].next =Head[u]; $Head[u] = tot++;Panax Notoginseng } - voidInit () the { +tot =0; AMemset (Head,-1,sizeof(head)); the } + intFA[MAXN][DEG];//Fa[i][j] Represents the first 2^j ancestor of node I - intDEG[MAXN];//Depth Array $  $ voidBFS (introot) - { -queue<int>que; theDeg[root] =0; -fa[root][0] =Root;Wuyi Que.push (root); the      while(!que.empty ()) -     { Wu         intTMP =Que.front (); - Que.pop (); About          for(inti =1; i < DEG; i++) $Fa[tmp][i] = fa[fa[tmp][i-1]][i-1]; -          for(inti = head[tmp]; I! =-1; i =edge[i].next) -         { -             intv =edge[i].to; A             if(v = = fa[tmp][0])Continue; +DEG[V] = deg[tmp] +1; thefa[v][0] =tmp; - Que.push (v); $         } the  the     } the } the intLCA (intUintv) - { in     if(Deg[u] >Deg[v]) Swap (U, v); the     intHu = Deg[u], HV =Deg[v]; the     intTu = u, TV =v; About      for(intDet = Hv-hu, i =0; Det Det >>=1, i++) the     if(Det &1) theTV =Fa[tv][i]; the     if(TU = TV)returntu; +      for(inti = DEG-1; I >=0; i--) -     { the         if(Fa[tu][i] = =Fa[tv][i])Bayi             Continue; theTu =Fa[tu][i]; theTV =Fa[tv][i]; -     } -     returnfa[tu][0]; the } the BOOLFLAG[MAXN]; the intMain () the { -Freopen ("In.txt","R", stdin); the     //freopen ("OUT.txt", "w", stdout); the     intT; the     intN;94     intu, v; thescanf"%d", &T); the      while(t--) the     {98scanf"%d", &n); About init (); -memset (Flag,false,sizeof(flag));101          for(inti =1; I < n; i++)102         {103scanf"%d%d", &u, &v);104 Addedge (U, v); the Addedge (V, u);106FLAG[V] =true;107         }108         intRoot;109          for(inti =1; I <= N; i++) the         if(!Flag[i])111         { theRoot =i;113              Break; the         } the BFS (root); thescanf"%d%d", &u, &v);117printf"%d\n", LCA (U, v));118     }119     return 0; -}

LCA of POJ 1330 Nearest Common Ancestors multiplication algorithm