摘要：
F2. Wrong Answer on test 233 (Hard Version) Your program fails again. This time it gets "Wrong answer on test 233" . This is the harder version of the 阅读全文
摘要：
E. Arson In Berland Forest The Berland Forest can be represented as an infinite cell plane. Every cell contains a tree. That is, contained before the 阅读全文
摘要：
D2. Optimal Subsequences (Hard Version) This is the harder version of the problem. In this version, 1≤n,m≤2⋅105. You can hack this problem if you lock 阅读全文
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 阅读全文
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 阅读全文
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 阅读全文