ACM思维题训练集合 A bracket sequence is a string containing only characters "(" and ")". A regular bracket sequence is a bracket sequence that can be transformed into a correct arithmetic expression by inserting characters "1" and &…
(CodeForces - 5C)Longest Regular Bracket Sequence time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output This is yet another problem dealing with regular bracket sequences. We should remind you t…
A bracket(括号) sequence is a string containing only characters "(" and ")".A regular bracket sequence is a bracket sequence that can be transformed into a correct arithmetic expression by inserting characters "1" and "+&q…
Bracket Sequences Concatenation Problem time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A bracket sequence is a string containing only characters "(" and ")". A regular bra…
C. Longest Regular Bracket Sequence Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/problemset/problem/5/C Description This is yet another problem dealing with regular bracket sequences. We should remind you that a bracket sequence…
题目链接 大意 给出一颗树,按下列方式生成一个括号序列. function dfs(int cur, int parent): print('(') for all nxt that cur is adjacent to: dfs(nxt, cur) print(')') 其中可以从任一点出发,且对儿子的遍历顺序是随机的. 求本质不同的括号序列个数. 思路 前置板块:树Hash 如何判断两颗有根树是否本质一样? 我们先随机生成一个\(T\)数组(随机数被卡概率小?) 令\(Siz[u]\)表示\…
Problem Codeforces #550 (Div3) - G.Two Merged Sequences Time Limit: 2000 mSec Problem Description Two integer sequences existed initially, one of them was strictly increasing, and another one — strictly decreasing. Strictly increasing sequence is a…
[链接]:CF Examples inputCopy ((?)) outputCopy 4 inputCopy ??()?? outputCopy 7 说明 For the first sample testcase, the pretty substrings of s s are: "(?" which can be transformed to "()". "?)" which can be transformed to "()&…
Decoding Morse Sequences 题目链接: http://acm.hust.edu.cn/vjudge/contest/129783#problem/D Description Before the digital age, the most common "binary" code for radio communication was the Morse code. In Morse code, symbols are encoded as sequences o…
描述 Given a string of digits, insert commas to create a sequence of strictly increasing numbers so as to minimize the magnitude of the last number. For this problem, leading zeros are allowed in front of a number. 输入 Input will consist of multiple tes…
B. Long Path time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output One day, little Vasya found himself in a maze consisting of (n + 1) rooms, numbered from 1 to (n + 1). Initially, Vasya is at th…
D. Bad Luck Island time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The Bad Luck Island is inhabited by three kinds of species: r rocks, s scissors and p papers. At some moments of time two…
Paladin Manao caught the trail of the ancient Book of Evil in a swampy area. This area contains n settlements numbered from 1 to n. Moving through the swamp is very difficult, so people tramped exactly n - 1 paths. Each of these paths connects some p…
Appleman has a tree with n vertices. Some of the vertices (at least one) are colored black and other vertices are colored white. Consider a set consisting of k (0 ≤ k < n) edges of Appleman's tree. If Appleman deletes these edges from the tree, then…
