柳下桃蹊

Given a string S consists of lower case letters. You're going to perform Q operations one by one. Ea

D Recently, Jvruo​ became obsessed with a fighting game. In this game, n​ characters stand on an are

B Fibonacci Sequence: f0=1 f1=1 fi=fi−1+fi−2,i≥2 Fibonacci representation F(x): Any natural number x

Problem Description During the War of Resistance Against Japan, tunnel warfare was carried out exten

F A snowflake graph is generated from two integers x and y, both greater than 1, as follows: Start w

C. Dreaming of Freedom time limit per test 2.5 seconds memory limit per test 256 megabytes input sta

一棵树上有n个节点，编号分别为1到n，每个节点都有一个权值w。我们将以下面的形式来要求你对这棵树完成一些操作： CHANGE u t，把结点u的权值改为t。 QMAX u v，询问从点u到点v的路径上

树链剖分 原理 树链剖分是根据轻重儿子，将一棵树剖成多条链，然后就可以用数据结构来维护这些链了，听着似乎还是有点像暴力，不过因为一条链有多个结点，所以可以优化时间复杂度。 树上LCA2 给你一棵 n 

C Princess Celestia, is an Alicorn pony, the former co-ruler of Equestria alongside her younger sist