Brackets Problem Description We give the following inductive definition of a “regular brackets” sequence:● the empty sequence is a regular brackets sequence,● if s is a regular brackets sequence, then (s) are regular brackets sequences, and● if a and…
BC # 32 1003 题意:定义了括号的合法排列方式,给出一个排列的前一段,问能组成多少种合法的排列. 这道题和鹏神研究卡特兰数的推导和在这题中的结论式的推导: 首先就是如何理解从题意演变到卡特兰数: 排列的总长度为 n ,左右括号各为 m = n / 2 个.当给定的排列方式完全合法的时候,剩下需要排列的左右括号的数量就已经确定了,而在排列的过程中,左括号要始终大于等于右括号的数量.设现在有 a 个左括号, b 个右括号,那么这个就可以当做从( a , b )点到 ( m , m )点且不…
Brackets Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 659 Accepted Submission(s): 170 Problem Description We give the following inductive definition of a “regular brackets” sequence: ● the…
传送门 zhx and contest Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 145 Accepted Submission(s): 49 Problem Description As one of the most powerful brushes in the world, zhx usually takes part…
传送门 zhx's contest Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 575 Accepted Submission(s): 181 Problem Description As one of the most powerful brushes, zhx is required to give his juniors…
Saving HDU Time Limit: 3000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 7194 Accepted Submission(s): 3345 Problem Description 话说上回讲到海东集团面临内外交困,公司的元老也只剩下XHD夫妇二人了.显然,作为多年拼搏的商人,XHD不会坐以待毙的. 一天,当他正在苦思冥想解困良策的…
http://acm.hdu.edu.cn/showproblem.php?pid=3037 Lucas定理模板. 现在才写,noip滚粗前兆QAQ #include<cstdio> #include<cstring> #include<algorithm> using namespace std; typedef long long ll; int jc[100003]; int p; int ipow(int x, int b) { ll t = 1, w = x;…
