BZOJ 4771: 七彩树

#include<algorithm>
#include<iostream>
#include<cstring>
#include<cstdio>
#include<set>
//by NeighThorn
#define min(a,b) a<b?a:b
using namespace std;

const int maxn=100000+5,maxm=10000000+5;

int ls[maxm],rs[maxm],sum[maxm],root[maxn],son[maxn],siz[maxn],top[maxn];
int n,m,ans,cas,cnt,tim,tot,c[maxn],hd[maxn],to[maxn],fa[maxn][25],nxt[maxn],dfn[maxn],dep[maxn],End[maxn],node[maxn];

/*
struct cmp{
	 bool operator () (int a,int b){
		return dfn[a]<dfn[b];
	}
};

set<int,cmp> v[maxn];
set<int,cmp>::iterator it;
*/

typedef pair<int,int> P;

set<P> v[maxn];
set<P>::iterator it,l,s;

inline int read(void){
	char ch=getchar();int x=0,f=1;
	while(!(ch>=‘0‘&&ch<=‘9‘)){
		if(ch==‘-‘) f=-1;
		ch=getchar();
	}
	while(ch>=‘0‘&&ch<=‘9‘) x=x*10+ch-‘0‘,ch=getchar();
	return f*x;
}

inline void add(int x,int y){
	to[cnt]=y;nxt[cnt]=hd[x];hd[x]=cnt++;
}

inline void dfs(int x){
	siz[x]=1;
	for(int i=hd[x];i!=-1;i=nxt[i]){
		fa[to[i]][0]=x,dep[to[i]]=dep[x]+1,dfs(to[i]);
		siz[x]+=siz[to[i]];
		if(siz[son[x]]<siz[to[i]])
			son[x]=to[i];
	}
}

inline void dfs2(int x,int t){
	dfn[x]=++tim;top[x]=t;
	if(son[x]==0){
		End[x]=tim;return;
	}
	dfs2(son[x],t);
	for(int i=hd[x];i!=-1;i=nxt[i])
		if(to[i]!=son[x])
			dfs2(to[i],to[i]);
	End[x]=tim;son[x]=0;
}

inline int LCA(int x,int y){
	while(top[x]!=top[y]){
		if(dep[top[x]]<dep[top[y]])
			swap(x,y);
		x=fa[top[x]][0];
	}
	if(dep[x]<dep[y])
		swap(x,y);
	return y;
}

inline void change(int l,int r,int pos,int val,int x,int &y){
	y=++tot;sum[y]=sum[x]+val;
	if(l==r)
		return;
	int mid=(l+r)>>1;ls[y]=ls[x];rs[y]=rs[x];
	if(pos<=mid)
		change(l,mid,pos,val,ls[x],ls[y]);
	else
		change(mid+1,r,pos,val,rs[x],rs[y]);
	
}

inline int query(int l,int r,int y,int L,int R){
	if(l==L&&R==r)
		return sum[y];
	int mid=(l+r)>>1;
	if(R<=mid)
		return query(l,mid,ls[y],L,R);
	else if(L>mid)
		return query(mid+1,r,rs[y],L,R);
	else
		return query(l,mid,ls[y],L,mid)+query(mid+1,r,rs[y],mid+1,R);
}

inline bool cmp(int x,int y){
	return dep[x]<dep[y];
}

signed main(void){
//	freopen("paint.in","r",stdin);
//	freopen("paint.out","w",stdout);
	cas=read();
	while(cas--){
		memset(hd,-1,sizeof(hd));
		n=read(),m=read();cnt=0;
		for(int i=1;i<=n;i++)
			c[i]=read(),node[i]=i;
		for(int i=2,x;i<=n;i++)
			x=read(),add(x,i);
		fa[1][0]=1;dep[1]=0;tim=tot=0;dfs(1);ans=0;dfs2(1,1);
		sort(node+1,node+n+1,cmp);root[0]=0;
		for(int i=1,x,y;i<=n;i++){
			x=node[i];y=node[i-1];
			change(1,n,dfn[x],1,root[dep[y]],root[dep[x]]);
			if(!v[c[x]].empty()){
				v[c[x]].insert(P(dfn[x],x));
				it=v[c[x]].find(P(dfn[x],x));it--;s=it;
				it=v[c[x]].find(P(dfn[x],x));it++;l=it;
				if(l!=v[c[x]].end()&&s!=v[c[x]].end()) change(1,n,dfn[LCA(l->second,s->second)], 1,root[dep[x]],root[dep[x]]);
				if(l!=v[c[x]].end())                   change(1,n,dfn[LCA(x        ,l->second)],-1,root[dep[x]],root[dep[x]]);
				if(s!=v[c[x]].end())                   change(1,n,dfn[LCA(s->second,x        )],-1,root[dep[x]],root[dep[x]]);
			}
			else
				v[c[x]].insert(P(dfn[x],x));
		}
		for(int i=1;i<=n;i++)
			v[i].clear();
		for(int i=1,x,d;i<=m;i++){
			x=read(),d=read();x^=ans,d^=ans;
			printf("%d\n",ans=query(1,n,root[min(dep[x]+d,dep[node[n]])],dfn[x],End[x]));
		}
	}
	return 0;
}