LCA在线算法

#include<stdio.h>#include<iostream>#include<algorithm>#include<vector>#include<string.h>#define max 400005using namespace std;int deap[max],vis[max],dis[max],kk[32][max];int maxlog;struct pi{    int to;    int cost;}pp;vector<pi>g[max];void init(int v,int p,int d){    vis[v]=1;    deap[v]=d;    int i,k;     kk[0][v]=p;    for(i=1;i<maxlog;i++)    {        if(kk[i-1][v]<0)            kk[i][v]=-1;        else        {            kk[i][v]=kk[i-1][kk[i-1][v]];        }    }    k=g[v].size();    for(i=0;i<k;i++)    {        if(!vis[g[v][i].to])        {            dis[g[v][i].to]=dis[v]+g[v][i].cost;            init(g[v][i].to,v,d+1);        }    }    return ;}int find(int a,int b){    if(deap[a]>deap[b])        swap(a,b);    int i,f;    f=deap[b]-deap[a];    for(i=0;i<maxlog;i++)    {        if((f>>i)&1)            b=kk[i][b];    }    if(b==a)        return a;    for(i=maxlog-1;i>=0;i--)    {        if(kk[i][a]!=kk[i][b])        {            a=kk[i][a];            b=kk[i][b];        }    }    return kk[0][a];}int solve(int a,int b){    int f;    f=find(a,b);    return dis[a]+dis[b]-2*dis[f];}