问题相当于统计$且\sum_{l\le x<y\le r且lca(x,y)=x}1=c(sz[x],2)-\sum_{son}c(sz[son],2)$,考虑用莫队来维护区间,那么相当于要支持:1.某个点到根的链修改:2.询问某个点的上述式子 树链剖分维护:对于轻儿子,将这个权值加入父亲,复杂度$o(n\sqrt{n}\log n)$:对于重儿子,由于只有单点,用可持久化线段树来维护,复杂度$o(n\log n)$ 由于复杂度较高,可能需要卡一下常数 1 #include<bits/stdc+…

Implement a data structure supporting the following operations: Inc(Key) - Inserts a new key with value 1. Or increments an existing key by 1. Key is guaranteed to be a non-empty string. Dec(Key) - If Key's value is 1, remove it from the data structu…

Design a data structure that supports the following two operations: void addWord(word) bool search(word) search(word) can search a literal word or a regular expression string containing only letters a-z or .. A . means it can represent any one letter…

Design and implement a TwoSum class. It should support the following operations:add and find. add - Add the number to an internal data structure.find - Find if there exists any pair of numbers which sum is equal to the value. For example,add(1); add(…

http://staff.city.ac.uk/~ross/papers/FingerTree.html Summary We present 2-3 finger trees, a functional representation of persistent sequences supporting access to the ends in amortized constant time, and concatenation and splitting in time logarithmi…

Mesh Data Structure in OpenCascade eryar@163.com 摘要Abstract:本文对网格数据结构作简要介绍,并结合使用OpenCascade中的数据结构,将网格数据在OpenSceneGraph中可视化. 关键字KeyWords:OpenCascade.OpenSceneGraph.Triangulation.Mesh Data Structure 一.引言 Introduction 三角网格就是全部由三角形组成的多边形网格.多边形和三角网格在图形学和建…

Design and implement a TwoSum class. It should support the following operations: add and find. add - Add the number to an internal data structure.find - Find if there exists any pair of numbers which sum is equal to the value. For example, add(1); ad…

我要在这里装个逼啦 class WordDictionary(object): def __init__(self): """ initialize your data structure here. """ self._dict = {} def addWord(self, word): """ Adds a word into the data structure. :type word: str :rtype:…

Design a data structure that supports the following two operations: void addWord(word)bool search(word) search(word) can search a literal word or a regular expression string containing only letters a-z or .. A . means it can represent any one letter.…

题目 Source http://acm.hdu.edu.cn/showproblem.php?pid=5739 Description Professor Zhang has an undirected graph G with n vertices and m edges. Each vertex is attached with a weight wi. Let Gi be the graph after deleting the i-th vertex from graph G. Pro…