树链剖分模版

const  int maxn=10000+5;const  int maxm=maxn+maxn;int v[maxm];int prev[maxm];int info[maxm];int q[maxn];int idx[maxn];int dep[maxn];int size[maxn];int belong[maxn];int father[maxn];bool vis[maxn] ;int head[maxn];int len[maxn];int l,r,ans,cnt=0;int n,nedge=0;inline void insert(int x,int y){++negde;v[nedge]=y;prev[nedge]=info[x];info[x]=nedge;} void split(){memset(dep,-1,sizeof(dep));l=0;dep[q[r=1]=1]=0;father[1]=-1;while(l<r){int x=q[++l];for(int y=info[x];y;y=prev[y]){if(dep[v[y]]==-1){dep[q[++r]=v[y]]=dep[x]+1;father[v[y]]=x;}}}for(int i=n;i;i--){int x=q[i],p=-1;size[x]=1;for(int y=info[x];y;y=prev[y])  if(vis[v[y]]) {  size[x]+=size[v[y]];  if(p==-1||size[v[y]]>size[p])     p=v[y];  }  if(p==-1){  idx[x]=len[++cnt]=1;  belong[head[cnt]=x]=cnt;  }  else{  idx[x]=++len[belong[x]=belong[p]];  head[belong[x]]=x;  }  vis[x]=true;}}