[BZOJ3730]震波

description

题面

solution

动态点分治第三题。

动态维护与某点距离\(\le k\)的所有点的点权和.

对于每一个节点开两棵线段树:一棵维护以距离为下标的点权和,
一棵维护对父亲的贡献。

没写过线段树动态开点...
于是就改成了树状数组...

弱

code

#include<bits/stdc++.h>
#include<algorithm>
#include<iostream>
#include<fstream>
#include<cstdlib>
#include<iomanip>
#include<cstring>
#include<complex>
#include<clocale>
#include<cctype>
#include<vector>
#include<cstdio>
#include<string>
#include<bitset>
#include<ctime>
#include<cmath>
#include<queue>
#include<stack>
#include<list>
#include<map>
#include<set>
#define FILE "a"
#define mp make_pair
#define pb push_back
#define RG register
#define il inline
#define RAND
using namespace std;
typedef unsigned long long ull;
typedef vector<int>VI;
typedef long long ll;
typedef double dd;
const int inf=2147483647;
const dd pi=acos(-1);
const dd eps=1e-10;
const int mod=1e9+7;
const int N=100010;
const ll INF=1e18+1;
il ll read(){
	RG ll data=0,w=1;RG char ch=getchar();
	while(ch!='-'&&(ch<'0'||ch>'9'))ch=getchar();
	if(ch=='-')w=-1,ch=getchar();
	while(ch<='9'&&ch>='0')data=data*10+ch-48,ch=getchar();
	return data*w;
}
il int make(int l,int r){return rand()%(r-l+1)+l;}
il void file(){	
	freopen(FILE".in","r",stdin);
	freopen(FILE".out","w",stdout);
}
/*********************************************************************/

int n,m,val[N];
int head[N],nxt[N<<1],to[N<<1],cnt;
il void add(int u,int v){
	to[++cnt]=v;
	nxt[cnt]=head[u];
	head[u]=cnt;
}
int pa[N],siz[N],deb[N],top[N],son[N];
void dfs1(int u,int ff){
	siz[u]=1;pa[u]=ff;son[u]=0;deb[u]=deb[ff]+1;
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==ff)continue;
		dfs1(v,u);siz[u]+=siz[v];
		if(!son[u]||siz[son[u]]<siz[v])son[u]=v;
	}
}
void dfs2(int u,int tp){
	top[u]=tp;if(son[u])dfs2(son[u],tp);
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==pa[u]||v==son[u])continue;
		dfs2(v,v);
	}
}
il int lca(int u,int v){
	while(top[u]!=top[v]){
		if(deb[top[u]]<deb[top[v]])swap(u,v);
		u=pa[top[u]];
	}
	return deb[u]<deb[v]?u:v;
}
il int dist(int u,int v){return deb[u]+deb[v]-2*deb[lca(u,v)];}
/*********************************************************************/

int RT,rt,block,sz[N],w[N],fa[N],dep[N];bool vis[N];
#define lowbit(x) ((x)&(-(x)))
struct BIT{
	vector<int> ret;
	il int maxdep(){return ret.size()-1;}
	il void insert(int D,int v){
		RG int len=ret.size();while(len-1<D){ret.pb(0);len++;}
		for(D;D<len;D=(D+1)+lowbit(D+1)-1)ret[D]+=v;
	}
	il int query(int k){
		RG int s=0,len=ret.size();
		for(k;~k;k=(k+1)-lowbit(k+1)-1)s+=ret[k];return s;
	}
}sum[N],tofa[N];
void getsmd(int u,int ff,int nw){
	dep[u]=dep[ff]+1;sum[nw].insert(dep[u]-1,0);
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==ff||vis[v])continue;
		getsmd(v,u,nw);
	}
}
void getsum(int u,int ff,int nw){
	dep[u]=dep[ff]+1;sum[nw].insert(dep[u]-1,val[u]);
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==ff||vis[v])continue;
		getsum(v,u,nw);
	}
}
void gettmd(int u,int ff,int nw){
	dep[u]=dep[ff]+1;tofa[nw].insert(dep[u],0);
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==ff||vis[v])continue;
		gettmd(v,u,nw);
	}	
}
void gettofa(int u,int ff,int nw){
	dep[u]=dep[ff]+1;tofa[nw].insert(dep[u],val[u]);
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==ff||vis[v])continue;
		gettofa(v,u,nw);
	}
}
void getrt(int u,int ff){
	sz[u]=1;w[u]=0;
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==ff||vis[v])continue;
		getrt(v,u);sz[u]+=sz[v];
		w[u]=max(w[u],sz[v]);
	}
	w[u]=max(w[u],block-sz[u]);if(w[rt]>w[u])rt=u;
}
void solve(int u,int ff){
	getsmd(u,0,u);getsum(u,0,u);fa[u]=ff;vis[u]=1;
	for(RG int i=head[u];i;i=nxt[i]){
		RG int v=to[i];if(v==ff||vis[v])continue;
		block=sz[v];rt=0;
		getrt(v,0);gettmd(v,0,rt);gettofa(v,0,rt);solve(rt,u);
	}
}
/*********************************************************************/

il void Mod(int x,int y){
	y=y-val[x];val[x]+=y;RG int d=0;sum[x].insert(d,y);
	for(RG int u=x;fa[u];u=fa[u])
		d=dist(x,fa[u]),tofa[u].insert(d,y),sum[fa[u]].insert(d,y);
}
il int Qry(int x,int k){
	RG int D,s=sum[x].query(min(k,sum[x].maxdep()));
	for(RG int u=x;fa[u];u=fa[u]){
		D=dist(x,fa[u]);if(k<D)continue;
		s-=tofa[u].query(min(k-D,tofa[u].maxdep()));
		s+=sum[fa[u]].query(min(k-D,sum[fa[u]].maxdep()));
	}
	return s;
}
/*********************************************************************/

int ans;
int main()
{
	n=read();m=read();
	for(RG int i=1;i<=n;i++)val[i]=read();
	for(RG int i=1,u,v;i<n;i++)u=read(),v=read(),add(u,v),add(v,u);		
	dfs1(1,0);dfs2(1,1);w[0]=block=n;RT=rt=0;getrt(1,0);solve(rt,0);
	for(RG int i=1,o,x,y;i<=m;i++){
		o=read();x=read()^ans;y=read()^ans;
		o?Mod(x,y),0:printf("%d\n",ans=Qry(x,y));
	}
	return 0;
}