CF1451B-Non-Substring Subsequence 题目: 题目描述: Hr0d1y has $ q $ queries on a binary string $ s $ of length $ n $ . A binary string is a string containing only characters ‘0’ and ‘1’. A query is described by a pair of integers $ l_i $ , $ r_i $ $ (1 \leq l_i \lt r_i \leq n) $ . For each query,
CF1451A-Subtract or Divide 题目: 题目描述: Ridbit starts with an integer $ n $ . In one move, he can perform one of the following operations: divide $ n $ by one of its proper divisors, or subtract $ 1 $ from $ n $ if $ n $ is greater than $ 1 $ . A proper divisor is a divisor of a number,
P5338-[TJOI2019]甲苯先生的滚榜 题目: 题目描述: 甲苯先生在制作一个 Online Judge，他发现做比赛的人们很关心自己的排名（显而易见）
P4559-[JSOI2018]列队 题目: 题目描述: 作为一名大学生，九条可怜在去年参加了她人生中的最后一次军训。 军训中的一个重要项目是练习列
AT4831-[ABC155F] Perils in Parallel 题目: 题目描述: AlDebaran 王国の侵攻によって、AtCoder 王国の各地に爆弾が仕掛けられてしまいました。 幸いにも AtCoder 王国 ABC 隊の健闘により制御装
CF915F-Imbalance Value of a Tree 题目: 题目描述: You are given a tree $ T $ consisting of $ n $ vertices. A number is written on each vertex; the number written on vertex $ i $ is $ a_{i} $ . Let’s denote the function $ I(x,y) $ as the difference between maximum and minimum value of $ a_{i} $ on a simple path
