题目:http://poj.org/problem?id=3294 Life Forms Time Limit: 5000MS Memory Limit: 65536K Total Submissions: 18549 Accepted: 5454 Description You may have wondered why most extraterrestrial life forms resemble humans, differing by superficial traits s
1811. Longest Common Substring Problem code: LCS A string is finite sequence of characters over a non-empty finite set Σ. In this problem, Σ is the set of lowercase letters. Substring, also called factor, is a consecutive sequence of characters occur
摘要:本文讨论了最长公共子串的的相关算法的时间复杂度,然后在后缀数组的基础上提出了一个时间复杂度为o(n^2*logn),空间复杂度为o(n)的算法.该算法虽然不及动态规划和后缀树算法的复杂度低,但其重要的优势在于可以编码简单,代码易于理解,适合快速实现. 首先,来说明一下,LCS通常指的是公共最长子序列(Longest Common Subsequence,名称来源参见<算法导论>原书第3版p223),而不是公共最长子串(也称为最长公共子串). 最长公共子串问题是在文本串.模式串中寻找共有的
Language: Default Long Long Message Time Limit: 4000MS Memory Limit: 131072K Total Submissions: 21228 Accepted: 8708 Case Time Limit: 1000MS Description The little cat is majoring in physics in the capital of Byterland. A piece of sad news comes
题意: 给定两个字符串 A 和 B,求最长公共子串. 分析: 字符串的任何一个子串都是这个字符串的某个后缀的前缀. 求 A 和 B 的最长公共子串等价于求 A 的后缀和 B 的后缀的最长公共前缀的最大值.如果枚举 A和 B 的所有的后缀,那么这样做显然效率低下. 由于要计算 A 的后缀和 B 的后缀的最长公共前缀,所以先将第二个字符串写在第一个字符串后面,中间用一个没有出现过的字符隔开,再求这个新的字符串的后缀数组. 观察一下,看看能不能从这个新的字符串的后缀数组中找到一些规律.以 A=“aaa
Long Long Message Time Limit: 4000MS Memory Limit: 131072K Total Submissions: 25752 Accepted: 10483 Case Time Limit: 1000MS Description The little cat is majoring in physics in the capital of Byterland. A piece of sad news comes to him these days
4493: DNA 题目连接: http://acm.scu.edu.cn/soj/problem.action?id=4493 Description Deoxyribonucleic acid (DNA) is a molecule that carries most of the genetic instructions used in the development, functioning and reproduction of all known living organisms a