题目 Source http://acm.hdu.edu.cn/showproblem.php?pid=4787 Description Now Coach Pang is preparing for the Graduate Record Examinations as George did in 2011. At each day, Coach Pang can: "+w": learn a word w "?p": read a paragraph p, an
C. Sereja and Brackets time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Sereja has a bracket sequence s1, s2, ..., sn, or, in other words, a string s of length n, consisting of characters "(
4568: [Scoi2016]幸运数字 Time Limit: 60 Sec Memory Limit: 256 MBSubmit: 238 Solved: 113[Submit][Status][Discuss] Description A 国共有 n 座城市,这些城市由 n-1 条道路相连,使得任意两座城市可以互达,且路径唯一.每座城市都有一个幸运数字,以纪念碑的形式矗立在这座城市的正中心,作为城市的象征.一些旅行者希望游览 A 国.旅行者计划乘飞机降落在 x 号城市,沿着 x 号城市
D. Acyclic Organic Compounds You are given a tree T with n vertices (numbered 1 through n) and a letter in each vertex. The tree is rooted at vertex 1. Let's look at the subtree Tv of some vertex v. It is possible to read a string along each simple
Tunnel Warfare Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Problem Description During the War of Resistance Against Japan, tunnel warfare was carried out extensively in the vast