BZOJ4012 [HNOI2015]开店

#include<cstdio>
#include<cstring>
#include<cctype>
#include<algorithm>
#define rep(s,t) for(int i=s;i<=t;i++)
#define ren for(int i=first[x];i;i=next[i])
using namespace std;
inline int read() {
    char ch=getchar();int x=0,f=1;
    for(;!isdigit(ch);ch=getchar()) if(ch==‘-‘) f=-1;
    for(;isdigit(ch);ch=getchar()) x=x*10+ch-‘0‘;
    return x*f;
}
const int maxn=300010;
typedef long long LL;
int n,q,first[maxn],next[maxn],to[maxn],dis[maxn],e;
void AddEdge(int w,int v,int u) {
     to[++e]=v;dis[e]=w;next[e]=first[u];first[u]=e;
     to[++e]=u;dis[e]=w;next[e]=first[v];first[v]=e;     
}
int mn[maxn][20],dep[maxn],pos[maxn],cnt;
void dfs(int x,int fa) {
     mn[++cnt][0]=dep[x];pos[x]=cnt;
     ren if(to[i]!=fa) {
         dep[to[i]]=dep[x]+dis[i];
         dfs(to[i],x);    
         mn[++cnt][0]=dep[x];
     }
}
int Log[maxn];
void init() {
     Log[0]=-1;rep(1,cnt) Log[i]=Log[i>>1]+1;
     for(int j=1;(1<<j)<=cnt;j++)
        for(int i=1;i+(1<<j)-1<=cnt;i++)
           mn[i][j]=min(mn[i][j-1],mn[i+(1<<j-1)][j-1]);     
}
LL dist(int x,int y) {
    LL ans=dep[x]+dep[y];x=pos[x];y=pos[y];if(x>y) swap(x,y);
    int k=Log[y-x+1];
    return ans-2LL*min(mn[x][k],mn[y-(1<<k)+1][k]);    
}
int age[maxn],vis[maxn],f[maxn],s[maxn],size,root;
void getroot(int x,int fa) {
     s[x]=1;int maxs=0;
     ren if(!vis[to[i]]&&to[i]!=fa) getroot(to[i],x),s[x]+=s[to[i]],maxs=max(maxs,s[to[i]]);
     f[x]=max(maxs,size-s[x]);
     if(f[root]>f[x]) root=x;     
}
struct Arr {
     int c;LL val;
     bool operator < (const Arr& ths) const {return c<ths.c;}
     Arr operator - (const Arr& ths) const {Arr t;t.val=val-ths.val;t.c=c-ths.c;return t;}
}A[maxn*30];
int cur,L1[maxn],R1[maxn],L2[maxn],R2[maxn];
void dfs(int x,int fa,int dep) {
     A[++cur]=(Arr){age[x],dep};s[x]=1;
     ren if(to[i]!=fa&&!vis[to[i]]) dfs(to[i],x,dep+dis[i]),s[x]+=s[to[i]];
}
int fa[maxn];
void solve(int x,int F) {
     vis[x]=1;fa[x]=F;
     A[++cur]=(Arr){-1,0};L1[x]=cur;dfs(x,0,0);R1[x]=cur;
     sort(A+L1[x],A+R1[x]+1);
     rep(L1[x]+1,R1[x]) A[i].val+=A[i-1].val;
     ren if(!vis[to[i]]) {
         size=f[0]=s[to[i]];getroot(to[i],root=0);
         A[++cur]=(Arr){-1,0};L2[root]=cur;dfs(to[i],0,dis[i]);R2[root]=cur;
         sort(A+L2[root],A+R2[root]+1);
         rep(L2[root]+1,R2[root]) A[i].val+=A[i-1].val;
         solve(root,x);
     }
}
LL lastans,T;
Arr get(int x,int ql,int qr,int L,int R) {
    Arr t;
    t.c=qr;
    int pos1=upper_bound(A+L,A+R+1,t)-A-1;
    t.c=ql-1;
    int pos2=upper_bound(A+L,A+R+1,t)-A-1;
    t.c=pos1-pos2;t.val=A[pos1].val-A[pos2].val;
    return t;
}
LL query(int x,int l,int r) {
    LL ret=get(x,l,r,L1[x],R1[x]).val;
    for(int i=x;fa[i];i=fa[i]) {
        Arr t=get(fa[i],l,r,L1[fa[i]],R1[fa[i]])-get(i,l,r,L2[i],R2[i]); 
        ret+=t.val+t.c*dist(fa[i],x);     
    }
    return ret;
}
int main() {
    n=read();q=read();T=read();
    rep(1,n) age[i]=read();
    rep(2,n) AddEdge(read(),read(),read());
    dfs(1,0);init();
    size=f[0]=n;getroot(1,root=0);
    int t=root;solve(root,0);root=t;
    while(q--) {
        int u=read(),a=(read()+lastans)%T,b=(read()+lastans)%T;
        if(a>b) swap(a,b);
        printf("%lld\n",lastans=query(u,a,b));
    }
    return 0;
}