灰鲭鲨

摘要： Problem StatementYou are given a tree with $N$ vertices. The vertices are numbered $1, \dots, N$, and the $i$-th ($1 \leq i \leq N - 1$) edge connects 阅读全文

摘要： 题目描述 The position of the leftmost maximum on the segment $ [l; r] $ of array $ x = [x_1, x_2, \ldots, x_n] $ is the smallest integer $ i $ such that $ 阅读全文

摘要： 题目描述 You are given three integers $ a $ , $ b $ , and $ d $ . Your task is to find any integer $ x $ which satisfies all of the following conditions, 阅读全文

摘要： Problem StatementA teacher has a hidden permutation $P=(P_1,P_2,\ldots,P_N)$ of $(1,2,\cdots,N)$. You are going to determine it. To do this, you prepa 阅读全文

摘要： Problem StatementTakahashi is trying to catch many Snuke. There are some pits in a two-dimensional coordinate plane, connected to Snuke's nest. Now, $ 阅读全文

摘要： Problem StatementYou are given integers $R$, $G$, $B$, and $K$. How many strings $S$ consisting of R, G, and B satisfy all of the conditions below? Fi 阅读全文

摘要： Ehab's REAL Number Theory Problem 题目描述 You are given an array $ a $ of length $ n $ that has a special condition: every element in this array has at m 阅读全文

摘要： # [NOIP2022] 建造军营 ## 题目描述 A 国与 B 国正在激烈交战中，A 国打算在自己的国土上建造一些军营。 A 国的国土由 $n$ 座城市组成，$m$ 条双向道路连接这些城市，使得**任意两座城市均可通过道路直接或间接到达**。A 国打算选择一座或多座城市（**至少一座**），并在这 阅读全文

摘要： The game is played by Alice and Bob. Initially, there are $n$ stones. The players alternate turns, making a move described below, with Alice going fir 阅读全文

摘要： Problem StatementConstruct a set $S$ of integers satisfying all of the conditions below. It can be proved that at least one such set $S$ exists under 阅读全文