BZOJ3626 LNOI2014LCA（树链剖分+主席树）

　　开店简化版。

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstdlib>
#include<cstring>
#include<algorithm>
using namespace std;
int read()
{
    int x=,f=;char c=getchar();
    while (c<''||c>'') {if (c=='-') f=-;c=getchar();}
    while (c>=''&&c<='') x=(x<<)+(x<<)+(c^),c=getchar();
    return x*f;
}
#define N 50010
#define P 201314
int n,m,q,t=,a[N],p[N];
int fa[N],top[N],id[N],size[N],son[N],cnt=;
struct data{int to,nxt;
}edge[N<<];
int root[N];
struct data2{int l,r,tag,x;
}tree[N<<];
void addedge(int x,int y){t++;edge[t].to=y,edge[t].nxt=p[x],p[x]=t;}
bool cmp(const int&x,const int&y)
{
    return a[x]<a[y];
}
void dfs1(int k)
{
    size[k]=;
    for (int i=p[k];i;i=edge[i].nxt)
    {
        fa[edge[i].to]=k;
        dfs1(edge[i].to);
        size[k]+=size[edge[i].to];
        if (size[edge[i].to]>size[son[k]]) son[k]=edge[i].to;
    }
}
void dfs2(int k,int from)
{
    top[k]=from;id[k]=++cnt;
    if (son[k]) dfs2(son[k],from);
    for (int i=p[k];i;i=edge[i].nxt)
    if (edge[i].to!=son[k])
    dfs2(edge[i].to,edge[i].to);
}
void inc(int &x,int y){x+=y;if (x>=P) x-=P;}
void add(int &k,int l,int r,int x,int y)
{
    if (x>y) return;
    tree[++cnt]=tree[k];k=cnt;
    inc(tree[k].x,y-x+);
    if (l==x&&r==y){tree[k].tag++;return;}
    int mid=l+r>>;
    if (y<=mid) add(tree[k].l,l,mid,x,y);
    else if (x>mid) add(tree[k].r,mid+,r,x,y);
    else add(tree[k].l,l,mid,x,mid),add(tree[k].r,mid+,r,mid+,y);
}
int query(int k,int l,int r,int x,int y,int tag)
{
    if (x>y) return ;
    if (l==x&&r==y) return (tree[k].x+1ll*(y-x+)*tag%P)%P;
    tag+=tree[k].tag;
    int mid=l+r>>;
    if (y<=mid) return query(tree[k].l,l,mid,x,y,tag);
    else if (x>mid) return query(tree[k].r,mid+,r,x,y,tag);
    else return (query(tree[k].l,l,mid,x,mid,tag)+query(tree[k].r,mid+,r,mid+,y,tag))%P;
}
void modify(int i,int x)
{
    while (x)
    {
        add(root[i],,n,id[top[x]],id[x]);
        x=fa[top[x]];
    }
}
int getans(int r,int l,int x)
{
    int s=;
    while (x)
    {
        inc(s,query(root[r],,n,id[top[x]],id[x],)-query(root[l],,n,id[top[x]],id[x],));
        if (s<) s+=P;
        x=fa[top[x]];
    }
    return s;
}
int main()
{
#ifndef ONLINE_JUDGE
    freopen("bzoj3626.in","r",stdin);
    freopen("bzoj3626.out","w",stdout);
    const char LL[]="%I64d\n";
#else
    const char LL[]="%lld\n";
#endif
    n=read(),q=read();
    for (int i=;i<=n;i++)
    {
        int x=read();
        addedge(x+,i);
    }
    dfs1();
    dfs2(,);
    cnt=;
    for (int i=;i<=n;i++)
    {
        root[i]=root[i-];
        modify(i,i);
    }
    for (int i=;i<=q;i++)
    {
        int l=read()+,r=read()+,x=read()+;
        printf("%d\n",getans(r,l-,x));
    }
    return ;
}