首先来看什么是最长公共子序列:给定两个序列,找到两个序列中均存在的最长公共子序列的长度.子序列需要以相关的顺序呈现,但不必连续.例如,"abc", "abg", "bdf", "aeg", '"acefg"等都是"abcdefg"的子序列.因此,一个长度为n的序列拥有2^n中可能的子序列(序列中的每一个元素只有选或者不选两种可能,因此是2^n). Example: LCS for inp…
Let's say we have two strings: str1 = 'ACDEB' str2 = 'AEBC' We need to find the longest common subsequence, which in this case should be 'AEB'. Using dynamic programming, we want to compare by char not by whole words. we need memo to keep tracking th…
在 Dynamic Programming | Set 1 (Overlapping Subproblems Property) 和 Dynamic Programming | Set 2 (Optimal Substructure Property) 中我们已经讨论了重叠子问题和最优子结构性质,现在我们来看一个可以使用动态规划来解决的问题:最长上升子序列(Longest Increasing Subsequence(LIS)). 最长上升子序列问题,致力于在一个给定的序列中找到一个最长的子序列…
1. 问题描述 子串应该比较好理解,至于什么是子序列,这里给出一个例子:有两个母串 cnblogs belong 比如序列bo, bg, lg在母串cnblogs与belong中都出现过并且出现顺序与母串保持一致,我们将其称为公共子序列.最长公共子序列(Longest Common Subsequence, LCS),顾名思义,是指在所有的子序列中最长的那一个.子串是要求更严格的一种子序列,要求在母串中连续地出现.在上述例子的中,最长公共子序列为blog(cnblogs, belong),最长公…
The Longest Common Subsequence (LCS) problem is as follows: Given two sequences s and t, find the length of the longest sequence r, which is a subsequence of both s and t. Do you know the difference between substring and subequence? Well, substring i…
link to problem Description: Given two strings text1 and text2, return the length of their longest common subsequence. A subsequence of a string is a new string generated from the original string with some characters(can be none) deleted without chan…
''' merge two configure files, basic file is aFile insert the added content of bFile compare to aFile for example, 'bbb' is added content ----------------------------------------------------------- a file content | b file content | c merged file cont…
原题链接在这里:http://www.lintcode.com/en/problem/longest-common-subsequence/ 题目: Given two strings, find the longest common subsequence (LCS). Your code should return the length of LCS. Clarification What's the definition of Longest Common Subsequence? htt…
Problem Introduction In this problem, your goal is to compute the length of a longest common subsequence of three sequences. Problem Description Task.Given three sequences \(A=(a_1,a_2,\cdots,a_n)\); \(B = (b_1, b_2,\cdots,b_m)\), and \(C=(c_1,c_2,\c…
最长公共子序列 英文缩写为LCS(Longest Common Subsequence).其定义是,一个序列 S ,如果分别是两个或多个已知序列的子序列,且是所有符合此条件序列中最长的,则 S 称为已知序列的最长公共子序列.而最长公共子串(要求连续)和最长公共子序列是不同的 应用 最长公共子序列是一个十分实用的问题,它可以描述两段文字之间的“相似度”,即它们的雷同程度,从而能够用来辨别抄袭.对一段文字进行修改之后,计算改动前后文字的最长公共子序列,将除此子序列外的部分提取出来,这种方法判断修改的…