Ch’s gift HDU

赛中init写漏了一行，多组样例T在第二组读入（

怪我懒得改模板。。。

#include<bits/stdc++.h>
#include<stdio.h>
#include<algorithm>
#include<queue>
#include<string.h>
#include<iostream>
#include<math.h>
#include<set>
#include<map>
#include<vector>
#include<iomanip>
using namespace std;
#define ll long long
#define ull unsigned long long
#define pb push_back
#define FOR(a) for(int i=1;i<=a;i++)
const int inf=0x3f3f3f3f;
const int maxn=1e5+7; 
const long long mod=998244353;

int n,m;
int arr[maxn];

struct EDGE{
    int v,nxt;
}G[maxn<<2];
int head[maxn],tot;
void addedge(int u,int v){
    ++tot;G[tot].v=v;G[tot].nxt=head[u];head[u]=tot;
}

int top[maxn];
int pre[maxn];
int dep[maxn];
int num[maxn];
int p[maxn];
int fp[maxn];
int son[maxn];
int pos;

void init(){
    memset(head,-1,sizeof head);tot=0;
	memset(son,0,sizeof son);pos=0;
}

void dfs1(int u,int fa,int d){
    dep[u]=d;
    pre[u]=fa;
    num[u]=1;
    for(int i=head[u];~i;i=G[i].nxt){
        int v=G[i].v;
        if(v==fa)continue;
        dfs1(v,u,d+1);
        num[u]+=num[v];
        if(son[u]==0 || num[v]>num[son[u]])son[u]=v;
    }
}
void getpos(int u,int sp){
    top[u]=sp;
    p[u]=++pos;
    fp[p[u]]=u;
    if(!son[u])return;
    getpos(son[u],sp);
    for(int i=head[u];~i;i=G[i].nxt){
        int v=G[i].v;
        if(v!=son[u] && v!=pre[u])getpos(v,v);
    }
}

struct NODE{
    int maxx;
    int minn;
    ll sum;
}ST[maxn<<2];

void pushup(int rt){
    if(ST[rt<<1].maxx>ST[rt<<1|1].maxx){
        ST[rt].maxx=ST[rt<<1].maxx;
    }else{
        ST[rt].maxx=ST[rt<<1|1].maxx;
    }
    ST[rt].sum=ST[rt<<1].sum+ST[rt<<1|1].sum;
}
void build(int l,int r,int rt){
    if(l==r){ST[rt].maxx=ST[rt].minn=ST[rt].sum=arr[fp[l]];
        return;
    }
    int m=l+r>>1;build(l,m,rt<<1);build(m+1,r,rt<<1|1);pushup(rt);
}

ll Squery(int a,int b,int l,int r,int rt,int lim,int rlim){    
    ll ans=0;
    if(a<=l && b>=r && ST[rt].minn>=lim && ST[rt].maxx<=rlim)
    {
        return ST[rt].sum;
    }else if(l==r)return 0;
    int m=l+r>>1;
    if(a<=m)ans+=Squery(a,b,l,m,rt<<1,lim,rlim);
    if(b>m)ans+=Squery(a,b,m+1,r,rt<<1|1,lim,rlim);
    return ans;    
}

ll work(int u,int v,int a,int b){//让树链st的[a,b]和出来
    ll ans=0;

    while(top[u]!=top[v]){
        if(dep[top[u]]<dep[top[v]])swap(u,v);
        ans+=Squery(p[top[u]],p[u],1,n,1,a,b);
        u=pre[top[u]];
    }
    if(dep[u]<dep[v])swap(u,v);
    ans+=Squery(p[v],p[u],1,n,1,a,b);
    return ans;
}

int main(){
    while(~scanf("%d%d",&n,&m)){
        init();
        for(int i=1;i<=n;i++){scanf("%d",&arr[i]);}
        for(int i=1,u,v;i<n;i++){
            scanf("%d%d",&u,&v);
            addedge(u,v);addedge(v,u);
        }
        
        dfs1(1,0,0);
        getpos(1,1);

		build(1,n,1);

        for(int i=1,s,t,a,b;i<=m;i++){
            scanf("%d%d%d%d",&s,&t,&a,&b);
              ll ans=work(s,t,a,b);
            if(i==1){
                printf("%lld",ans);
            }else{
                printf(" %lld",ans);
            }
        }
        puts("");
    }
}

编程真开心啊（吃药.jpg