随笔分类 - online judge Codeforces
摘要：C. Messy You are fed up with your messy room, so you decided to clean it up. Your room is a bracket sequence s=s1s2…sn of length n. Each character of
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摘要：B. Box Permutation p is a sequence of integers p=[p1,p2,…,pn], consisting of n distinct (unique) positive integers between 1 and n, inclusive. For exa
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摘要：A. Math Problem Your math teacher gave you the following problem: There are n segments on the x axis, [l1;r1],[l2;r2],…,[ln;rn]. The segment [l;r] inc
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摘要：E. The Contest A team of three programmers is going to play a contest. The contest consists of 𝑛 problems, numbered from 1 to 𝑛. Each problem is pri
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摘要：D. Yet Another Monster Killing Problem You play a computer game. In this game, you lead a party of 𝑚 heroes, and you have to clear a dungeon with 𝑛
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摘要：C. Dominated Subarray Let's call an array 𝑡 dominated by value 𝑣 in the next situation. At first, array 𝑡 should have at least 2 elements. Now, let
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摘要：B. Magic Stick Recently Petya walked in the forest and found a magic stick. Since Petya really likes numbers, the first thing he learned was spells fo
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摘要：A. Two Rival Students There are 𝑛 students in the row. And there are two rivalling students among them. The first one is in position 𝑎, the second i
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摘要：D. Catowice City In the Catowice city next weekend the cat contest will be held. However, the jury members and the contestants haven't been selected y
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摘要：C. Queue in the Train There are 𝑛 seats in the train's car and there is exactly one passenger occupying every seat. The seats are numbered from 1 to
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摘要：D2. The World Is Just a Programming Task (Hard Version) This is a harder version of the problem. In this version, 𝑛≤300000. Vasya is an experienced d
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摘要：B. Grow The Tree Gardener Alexey teaches competitive programming to high school students. To congratulate Alexey on the Teacher's Day, the students ha
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摘要：A. Integer Points DLS and JLS are bored with a Math lesson. In order to entertain themselves, DLS took a sheet of paper and drew 𝑛 distinct lines, gi
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摘要：A. Ivan the Fool and the Probability Theory Recently Ivan the Fool decided to become smarter and study the probability theory. He thinks that he under
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摘要：E. Connected Components? You are given an undirected graph consisting of n vertices and edges. Instead of giving you the edges that exist in the graph
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摘要：C. Sum Balance Ujan has a lot of numbers in his boxes. He likes order and balance, so he decided to reorder the numbers. There are 𝑘 boxes numbered f
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摘要：D. 0 1 MST Ujan has a lot of useless stuff in his drawers, a considerable part of which are his math notebooks: it is time to sort them out. This time
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摘要：C. Tile Painting Ujan has been lazy lately, but now has decided to bring his yard to good shape. First, he decided to paint the path from his house to
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摘要：B2. Character Swap (Hard Version) This problem is different from the easy version. In this version Ujan makes at most 2𝑛 swaps. In addition, 𝑘≤1000,
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摘要：B1. Character Swap (Easy Version) This problem is different from the hard version. In this version Ujan makes exactly one exchange. You can hack this
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