11 2023 档案
摘要:D2. Xor-Subsequence (hard version) It is the hard version of the problem. The only difference is that in this version . You are given an
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摘要:D1. Xor-Subsequence (easy version) It is the easy version of the problem. The only difference is that in this version . You are given an
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摘要:Count Beautiful Substrings II You are given a string s and a positive integer k. Let vowels and consonants be the number of vowels and consonants in a
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摘要:Make Lexicographically Smallest Array by Swapping Elements You are given a 0-indexed array of positive integers nums and a positive integer limit. In
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摘要:D. Small GCD Let , , and be integers. We define function as follows: Order the numbers , , in such a way that $a \le
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摘要:D. Ones and Twos You are given a -indexed array of length where each element is or . Process queries of the following two types:
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摘要:D. Letter Picking Alice and Bob are playing a game. Initially, they are given a non-empty string , consisting of lowercase Latin letters. The lengt
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摘要:【模板】可持久化线段树 2 题目背景 这是个非常经典的可持久化权值线段树入门题——静态区间第 小。 数据已经过加强,请使用可持久化权值线段树。同时请注意常数优化。 题目描述 如题,给定 个整数构成的序列 ,将对于指定的闭区间 查询其区间内的第 小值。
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摘要:F. A Growing Tree You are given a rooted tree with the root at vertex , initially consisting of a single vertex. Each vertex has a numerical value,
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摘要:D. Absolute Beauty Kirill has two integer arrays and of length . He defines the absolute beauty of the ar
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摘要:G. Unusual Entertainment A tree is a connected graph without cycles. A permutation is an array consisting of distinct integers from to in
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摘要:最近接触到一些 DFS 序的题,它可以用来解决一些关于子树的问题。 DFS 序本质就是一棵树在深度优先搜索时访问节点的顺序。比如有下面一棵树,其 DFS 序就是 。 DFS 序有一个很重要的性质,以节点 为
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摘要:[SHOI2007] 园丁的烦恼 题目背景 很久很久以前,在遥远的大陆上有一个美丽的国家。统治着这个美丽国家的国王是一个园艺爱好者,在他的皇家花园里种植着各种奇花异草。 有一天国王漫步在花园里,若有所思,他问一个园丁道: “最近我在思索一个问题,如果我们把花坛摆成六个六角形,那么……” “那么本质上
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摘要:F - Apples Problem Statement There are apple trees lined up on a number line, and apples fall from the trees.Specifically, for each $1\leq i\leq N
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摘要:【模板】扫描线 题目描述 求 个四边平行于坐标轴的矩形的面积并。 输入格式 第一行一个正整数 。 接下来 行每行四个非负整数 ,表示一个矩形的四个端点坐标为 $(x_1, y_1),(x_1, y_2),(x_2, y_2),(x_2,
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摘要:D. Score of a Tree You are given a tree of nodes, rooted at . Every node has a value of either or at time . At any integer time $t
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摘要:D. Counting Factorizations The prime factorization of a positive integer is the unique way to write it as $\displaystyle m=p_1^{e_1}\cdot p_2^{e_2
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摘要:[USACO22OPEN] Apple Catching G 题目描述 天上下苹果了!在某些时刻,一定数量的苹果会落到数轴上。在某些时刻,Farmer John 的一些奶牛将到达数轴并开始接苹果。 如果一个苹果在没有奶牛接住的情况下落到数轴上,它就会永远消失。如果一头奶牛和一个苹果同时到达,奶牛就会
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摘要:[BalticOI 2019 Day2] 汤姆的餐厅 题目背景 译自 BalticOI 2019 Day2 T1. Tom's Kitchen 题目描述 Tom's Kitchen 是一家非常受欢迎的餐厅,其受欢迎的原因之一是每份菜都由至少 名厨师进行准备。今天有 份菜需要准
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摘要:D. Neutral Tonality You are given an array consisting of integers, as well as an array consisting of integers. Let den
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摘要:城市环路 题目描述 一座城市,往往会被人们划分为几个区域,例如住宅区、商业区、工业区等等。 B 市就被分为了以下的两个区域——城市中心和城市郊区。在这两个区域的中间是一条围绕 B 市的环路,环路之内便是 B 市中心。 整个城市可以看做一个 个点, 条边的单圈图(保证图连通),唯一的环便
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摘要:[NOI2016] 区间 题目描述 在数轴上有 个闭区间从 至 编号,第 个闭区间为 。 现在要从中选出 个区间,使得这 个区间共同包含至少一个位置。换句话说,就是使得存在一个 ,使得对于每一个被选中的区间 $[l_i,r
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摘要:G. wxhtzdy ORO Tree After (finally) qualifying for the IOI 2023, wxhtzdy was very happy, so he decided to do what most competitive programmers do: try
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摘要:E1. Doremy's Drying Plan (Easy Version) The only differences between the two versions of this problem are the constraint on , the time limit and th
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摘要:D. XOR Construction You are given integers . Your task is to construct an array such that: ever
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