摘要：
F - Random Update Query Problem Statement You are given an integer sequence $A = (A_1, A_2, \ldots, A_N)$ of length $N$. We will perform the following 阅读全文
摘要：
E - Lucky bag Problem Statement AtCoder Inc. sells merchandise on its online shop. There are $N$ items remaining in the company. The weight of the $i$ 阅读全文
摘要：
[HNOI2009] 梦幻布丁 题目描述 $n$ 个布丁摆成一行，进行 $m$ 次操作。每次将某个颜色的布丁全部变成另一种颜色的，然后再询问当前一共有多少段颜色。 例如，颜色分别为 $1,2,2,1$ 的四个布丁一共有 $3$ 段颜色. 输入格式 第一行是两个整数，分别表示布丁个数 $n$ 和操作次 阅读全文
摘要：
G. Lights In the end of the day, Anna needs to turn off the lights in the office. There are $n$ lights and $n$ light switches, but their operation sch 阅读全文
摘要：
E. Good Triples Given a non-negative integer number $n$ ($n \ge 0$). Let's say a triple of non-negative integers $(a, b, c)$ is good if $a + b + c = n 阅读全文
摘要：
D. Robot Queries There is an infinite $2$-dimensional grid. Initially, a robot stands in the point $(0, 0)$. The robot can execute four commands: U — 阅读全文
摘要：
F - Palindrome Query Problem Statement You are given a string $S$ of length $N$ consisting of lowercase English letters.Process $Q$ queries described 阅读全文
摘要：
E. Permutation Sorting You are given a permutation$^\dagger$ $a$ of size $n$. We call an index $i$ good if $a_i=i$ is satisfied. After each second, we 阅读全文
摘要：
D2. Xor-Subsequence (hard version) It is the hard version of the problem. The only difference is that in this version $a_i \le 10^9$. You are given an 阅读全文
摘要：
D1. Xor-Subsequence (easy version) It is the easy version of the problem. The only difference is that in this version $a_i \le 200$. You are given an 阅读全文