http://acm.hdu.edu.cn/showproblem.php?pid=5763 题意: 给出一个字符串和一个模式串,模式串有两种意思,问这句话有几种意思. 思路:因为肯定要去字符串去找模式串,所以首先用KMP计算next数组,然后用动态规划,d[i]表示分析到第i个字符时有多少种意思. #include<iostream> #include<algorithm> #include<cstring> #include<cstdio> #inclu…

Another Meaning 题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=5763 Description As is known to all, in many cases, a word has two meanings. Such as "hehe", which not only means "hehe", but also means "excuse me". Today, ?? i…

[题目链接] http://acm.hdu.edu.cn/showproblem.php?pid=5763 [题目大意] 给出两个串S和T,可以将S串中出现的T替换为*,问S串有几种表达方式. [题解] 我们定义数组f为S串中T出现的最后一个字母所在的位置,那么ans[i]=ans[i-1]+f[i-1]?ans[i-lenT]:0,一遍递推即可,所以关键就在于求出f数组了,f数组可以用kmp求,由于最近练FFT,用FFT求距离卷积匹配为0的位置,就是f数组了. [代码] #include <c…

http://acm.hdu.edu.cn/showproblem.php?pid=4333 题意 一个数字,依次将第一位放到最后一位,问小于本身的数的个数及等于本身的个数和大于本身的个数,但是要注意重复的不再计算 分析 当这个串有循环节时才会出现重复串,用KMP的next数组来计算循环节:len-next[len].最后将得到的答案除以循环节个数即可.然后用扩展KMP,求出主串的后缀与模式串的前缀的最长公共前缀,这里的模式串是原串,而主串则是将两个原串连接起来.利用extend数组,当exte…

http://acm.hdu.edu.cn/showproblem.php?pid=5510 Bazinga Problem Description   Ladies and gentlemen, please sit up straight.Don't tilt your head. I'm serious.For n given strings S1,S2,⋯,Sn, labelled from 1 to n, you should find the largest i (1≤i≤n) su…

A Secret Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 256000/256000 K (Java/Others)Total Submission(s): 1530    Accepted Submission(s): 570 Problem Description Today is the birthday of SF,so VS gives two strings S1,S2 to SF as a present,wh…

[题目链接] http://acm.hdu.edu.cn/showproblem.php?pid=3613 [题目大意] 一个字符串的价值定义为,当它是一个回文串的时候,价值为每个字符的价值的和,如果不是回文串,价值为0,现在给出每种字符的价值.给出一个字符串,要求将其划分为两个子串,要求两个子串的价值和最大. [题解] 求出字符串S的反串T,以T为模板跑一遍S的exkmp就能得到S的后缀是否为回文串的信息,同理以S为模板跑一遍T就可以得到S的前缀是否是回文串的信息,枚举每个断点,取最大值即可.…

HDU 5763 Another Meaning 题意:一个字串有可能在模式串出现多次,问有多少种可能出现的情况.关键是有重合的字串是不能同时计入的. 思路:先用kmp求出所有字串的位置.然后,dp. 二维的时候:dp[i][j] i表示前i个子串,j的值1表示一定用这个串,0表示不用.值表示字串出现的情况数. 一维的时候可以直接用dp[i] 表示前i个字串能出现的情况. 然后,状态转移就都是分为三种情况: 1)当前子串和前一个子串不冲突,dp[i] = dp[i-1] * 2. 或者 dp[i…

HDU 2222 Keywords Search(查询关键字) Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 131072/131072 K (Java/Others) [Description] [题目描述] In the modern time, Search engine came into the life of everybody like Google, Baidu, etc. Wiskey also wants to br…

p.MsoNormal { margin: 0pt; margin-bottom: .0001pt; text-align: justify; font-family: Calibri; font-size: 10.5000pt } h1 { margin-top: 5.0000pt; margin-bottom: 5.0000pt; text-align: center; font-family: 宋体; color: rgb(26,92,200); font-weight: bold; fo…

HDU 5877 Weak Pair(弱点对) Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others) Description 题目描述 You are given a rooted tree of N nodes, labeled from 1 to N. To the ith node a non-negative value ai is assigned. An ordere…

HDU 5813 Elegant Construction(优雅建造) Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Description 题目描述 Being an ACMer requires knowledge in many fields, because problems in this contest may use physics, biology, and…

HDU 5818 Joint Stacks(联合栈) Time Limit: 8000/4000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Description 题目描述 A stack is a data structure in which all insertions and deletions of entries are made at one end, called the "top" of…

HDU 3549 Flow Problem(最大流) Time Limit: 5000/5000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) [Description] [题目描述] Network flow is a well-known difficult problem for ACMers. Given a graph, your task is to find out the maximum flow for t…

HDU  4548  美素数(打表)解题报告 题目链接:http://acm.hust.edu.cn/vjudge/contest/view.action?cid=88159#problem/H 题目: Description 小明对数的研究比较热爱,一谈到数,脑子里就涌现出好多数的问题,今天,小明想考考你对素数的认识.         问题是这样的:一个十进制数,如果是素数,而且它的各位数字和也是素数,则称之为“美素数”,如29,本身是素数,而且2+9 = 11也是素数,所以它是美素数.   …

HDU 1560 DNA sequence(DNA序列) Time Limit: 15000/5000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)   Problem Description - 题目描述 The twenty-first century is a biology-technology developing century. We know that a gene is made of DNA. Th…

HDU 1241 Oil Deposits(石油储藏) 00 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)   Problem Description - 题目描述 The GeoSurvComp geologic survey company is responsible for detecting underground oil deposits. GeoSurvComp works with one large…

取数字(dp优化) 给定n个整数\(a_i\),你需要从中选取若干个数,使得它们的和是m的倍数.问有多少种方案.有多个询问,每次询问一个的m对应的答案. \(1\le n\le 200000,1\le m\le 100,1\le q\le 30,-10^9\le a_i\le 10^9\). 首先有一个暴力dp:\(f[i][j]\)表示选到第i个数,和mod m是j的方案数.但是显然,这个dp是\(O(nm)\)的,然后就tle了. 换一个思路dp?由于我们只需要一个数模m的值,可以先把所有数…

洛谷P2507 [SCOI2008]配对 题解(dp+贪心) 标签:题解 阅读体验:https://zybuluo.com/Junlier/note/1299251 链接题目地址:洛谷P2507 [SCOI2008]配对 感觉是道很好的推断题 贪心 想到贪心的结论就很容易,没想到就很难做出来了 结论:对\(A,B\)数组分别排序之后,在\(A\)中选第\(i\)个数,与之配对的数一定在\(B[i-1]\)~\(B[i+1]\)内 其实证明是很好证的,在与你是否往这方面想了... 因为题目有一个很…

[Codeforces722E] Research Rover (dp+组合数学) 题面 给出一个N*M的方格阵,从(1,1)出发,到(N,M)结束,从(x,y)只能走到(x+1,y)或(x,y+1).方格阵上还有K个特殊点,初始时给出的分数t每经过一个特殊点就会变成\([\frac{t}{2}]\).求到(N,M)时得分的期望.保证(1,1)和(N,M)不是特殊点.\(N,M≤100000,\ K≤2000,\ t≤1000000\) 分析 考虑根据特殊点dp.把(1,1)和(n,m)也看作特…

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=5763 Another Meaning Time Limit: 2000/1000 MS (Java/Others)Memory Limit: 65536/65536 K (Java/Others) 问题描述 As is known to all, in many cases, a word has two meanings. Such as "hehe", which not only…

http://acm.hdu.edu.cn/showproblem.php?pid=5763 Another Meaning Problem Description   As is known to all, in many cases, a word has two meanings. Such as “hehe”, which not only means “hehe”, but also means “excuse me”. Today, ?? is chating with MeiZi…

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=5763 题目大意: T组数据,给两个字符串s1,s2(len<=100000),s2可以被解读成2种意思,问s1可以解读成几种意思(mod 1000000007). 题目思路: [动态规划][KMP] 题目有点绕,看看样例就懂了.其实不用KMP直接用substr就能做. 首先不解读成另一个意思的话,f[i]=f[i-1],接着如果当前位置能够与s2匹配,那么f[i]+=f[i-strlen(s2)]…

题目链接:http://acm.hdu.edu.cn/showproblem.php? pid=5389 Problem Description Zero Escape, is a visual novel adventure video game directed by Kotaro Uchikoshi (you may hear about ever17?) and developed by Chunsoft. Stilwell is enjoying the first chapter o…

Description Facer is addicted to a game called "Tidy is learning to swim". But he finds it too easy. So he develops a new game called "Facer is learning to swim" which is more difficult and more interesting. In the new game, a robot na…

题意: 国王的士兵有n个,每个人的身高都不同,国王要将他们排列,必须一高一矮间隔进行,即其中的一个人必须同时高于(或低于)左边和右边.问可能的排列数.例子有1千个,但是最多只算到20个士兵,并且20个的情况的答案已给出. 思路:是此题HDU 4055 Number String(DP计数) 的简单版,所以看此题解就行了.数量较小,可以预先算出来.要同时考虑 <><>和><><这样的两种情况. #include <iostream> #includ…

http://acm.hdu.edu.cn/showproblem.php?pid=4055 题意:给一个仅包含‘I','D','?'的字符串,’I'表示前面的数字比后面的数字要小(Increase升序),'D'表示前面的数字比前面的数字要大(Decrease降序),'?'表示有可能是'I'也有可能是'D',长度为n的字符串就有n+1个数字,在这n+1个数字里面,问符合给出的字符串的条件的序列数有多少种. 思路:dp[i][j]的定义:i表示当前枚举到第i个字符(即长度为i+1的时候的序列),j…

http://acm.hdu.edu.cn/showproblem.php?pid=5791 Two Problem Description   Alice gets two sequences A and B. A easy problem comes. How many pair of sequence A' and sequence B' are same. For example, {1,2} and {1,2} are same. {1,2,4} and {1,4,2} are not…

Best Financing Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 29    Accepted Submission(s): 3 Problem Description 小A想通过合理投资银行理财产品达到收益最大化.已知小A在未来一段时间中的收入情况,描述为两个长度为n的整数数组dates和earnings,表示在第dat…

Problem Description The signature of a permutation is a string that is computed as follows: for each pair of consecutive elements of the permutation, write down the letter 'I' (increasing) if the second element is greater than the first one, otherwis…