hdu5052 Yaoge’s maximum profit (树链剖分)

#include<bits/stdc++.h>
using namespace std;
#define N 50010
#define inf 0x7fffffff
inline int read(){
int x=0,f=1;char<
4000
/span> ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();
return x*f;
}
int n,m,h
,num=0,a
;
int size
,fa
,dep
,son
;
int id
,top
,dfn=0,w
;
struct edge{
int to,next;
}data[N<<1];
struct Data{
int x,mn,mx;
Data(){x=0;mn=inf;mx=0;}
Data operator+(Data b){
Data res;
res.mx=max(mx,b.mx);
res.mn=min(mn,b.mn);
res.x=max(x,b.x);
res.x=max(res.x,b.mx-mn);
return res;
}
};
struct node{
Data x,y;//x-- l->r最优解，y-- r->l最优解
int lazy;
}tree[N<<2];
void dfs1(int x){
size[x]=1;
for(int i=h[x];i;i=data[i].next){
int y=data[i].to;
if(fa[x]==y) continue;
fa[y]=x;dep[y]=dep[x]+1;dfs1(y);size[x]+=size[y];
if(size[y]>size[son[x]]) son[x]=y;
}
}
void dfs2(int x,int tp){
id[x]=++dfn;w[dfn]=a[x];top[x]=tp;
if(son[x]) dfs2(son[x],tp);
for(int i=h[x];i;i=data[i].next){
int y=data[i].to;
if(y==fa[x]||y==son[x]) continue;
dfs2(y,y);
}
}
inline void pushup(int p){
tree[p].x=tree[p<<1].x+tree[p<<1|1].x;
tree[p].y=tree[p<<1|1].y+tree[p<<1].y;
}
void build(int p,int l,int r){
tree[p].x.x=0;tree[p].y.x=0;tree[p].lazy=0;
if(l==r){
tree[p].x.mx=tree[p].y.mx=w[l];
tree[p].x.mn=tree[p].y.mn=w[l];return;
}
int mid=l+r>>1;
build(p<<1,l,mid);build(p<<1|1,mid+1,r);
pushup(p);
}
void pushdown(int p){
if(!tree[p].lazy) return;
tree[p<<1].lazy+=tree[p].lazy;tree[p<<1|1].lazy+=tree[p].lazy;
tree[p<<1].x.mx+=tree[p].lazy;tree[p<<1|1].x.mx+=tree[p].lazy;
tree[p<<1].x.mn+=tree[p].lazy;tree[p<<1|1].x.mn+=tree[p].lazy;
tree[p<<1].y.mx+=tree[p].lazy;tree[p<<1|1].y.mx+=tree[p].lazy;
tree[p<<1].y.mn+=tree[p].lazy;tree[p<<1|1].y.mn+=tree[p].lazy;
tree[p].lazy=0;
}
Data query(int p,int l,int r,int x,int y,bool f,int v){
if(x<=l&&r<=y){
tree[p].lazy+=v;tree[p].x.mn+=v;tree[p].x.mx+=v;
tree[p].y.mn+=v;tree[p].y.mx+=v;
return f?tree[p].x:tree[p].y;
}
int mid=l+r>>1;pushdown(p);Data res;
if(x<=mid) res=res+query(p<<1,l,mid,x,y,f,v);
if(y>mid) res= f?res+query(p<<1|1,mid+1,r,x,y,f,v):query(p<<1|1,mid+1,r,x,y,f,v)+res;
pushup(p);
return res;
}
void solve(int x,int y,int v){
Data ansl,ansr;
while(top[x]!=top[y]){
if(dep[top[x]]>=dep[top[y]]){
ansl=ansl+query(1,1,n,id[top[x]],id[x],0,v);//0-- x->top[x]
x=fa[top[x]];
}
else{
ansr=query(1,1,n,id[top[y]],id[y],1,v)+ansr;//1-- top[y]->y
y=fa[top[y]];
}
}
if(id[x]<id[y]) ansl=ansl+query(1,1,n,id[x],id[y],1,v);
else ansl=ansl+query(1,1,n,id[y],id[x],0,v);
ansl=ansl+ansr;
printf("%d\n",ansl.x);
}
int main(){
//  freopen("a.in","r",stdin);
int tt=read();
while(tt--){
n=read();num=dfn=0;
memset(fa,0,sizeof(fa));memset(son,0,sizeof(son));
memset(h,0,sizeof(h));
for(int i=1;i<=n;++i) a[i]=read();
for(int i=1;i<n;++i){
int x=read(),y=read();
data[++num].to=y;data[num].next=h[x];h[x]=num;
data[++num].to=x;data[num].next=h[y];h[y]=num;
}
dep[1]=1;dfs1(1);dfs2(1,1);build(1,1,n);
m=read();
while(m--){
int x=read(),y=read(),v=read();
solve(x,y,v);
}
}
return 0;
}