A sequence of numbers is called arithmetic if it consists of at least three elements and if the difference between any two consecutive elements is the same. For example, these are arithmetic sequences: 1, 3, 5, 7, 9 7, 7, 7, 7 3, -1, -5, -9 The follo…

Given a string s and a string t, check if s is subsequence of t. You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, and s is a short string (<=100). A subsequence of…

A sequence of numbers is called a wiggle sequence if the differences between successive numbers strictly alternate between positive and negative. The first difference (if one exists) may be either positive or negative. A sequence with fewer than two…

Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array. Formally the function should: Return true if there exists i, j, k such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k ≤ n-1 else return…

Given an unsorted array of integers, find the length of longest increasing subsequence. For example, Given [10, 9, 2, 5, 3, 7, 101, 18], The longest increasing subsequence is [2, 3, 7, 101], therefore the length is 4. Note that there may be more than…

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…

1. Description Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array. Formally the function should: Return true if there exists i, j, k such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k ≤…

D. Dense Subsequence time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given a string s, consisting of lowercase English letters, and the integer m. One should choose some symbols fr…

UVA - 11404 Palindromic Subsequence 题意:一个字符串,删去0个或多个字符,输出字典序最小且最长的回文字符串 不要求路径区间DP都可以做 然而要字典序最小 倒过来求LCS,转移同时维护f[i][j].s为当前状态字典序最小最优解 f[n][n].s的前半部分一定是回文串的前半部分(想想就行了) 当s的长度为奇时要多输出一个(因为这样长度+1,并且字典序保证最小(如axyzb  bzyxa,就是axb|||不全是回文串的原因是后半部分的字典序回文串可能不是最小,多…

Longest Increasing Subsequence(LIS) 一个美丽的名字 非常经典的线性结构dp [朴素]:O(n^2) d(i)=max{0,d(j) :j<i&&a[j]<a[i]}+1 直接两个for [二分查找优化]:O(n^2) g(i):d值为i的最小的a  每次更新然后lower_bound即可 ［大于等于］ lower_boundReturn iterator to lower bound Returns an iterator pointing…

Given a sequence of integers, find the longest increasing subsequence (LIS). You code should return the length of the LIS. Have you met this question in a real interview?     Example For [5, 4, 1, 2, 3], the LIS  is [1, 2, 3], return 3 For [4, 2, 4,…

Given a sequence of integers, find the longest increasing subsequence (LIS). You code should return the length of the LIS. Example For [5, 4, 1, 2, 3], the LIS  is [1, 2, 3], return 3 For [4, 2, 4, 5, 3, 7], the LIS is [4, 4, 5, 7], return 4 Challeng…

传送门:D Dense Subsequence 题意:输入一个m,然后输入一个字符串,从字符串中取出一些字符组成一个串,要求满足:在任意长度为m的区间内都至少有一个字符被取到,找出所有可能性中字典序最小的情况,并按字典序输出 思路:字典序 例如 aaaaaaab < ab  也就是说,如果满足要求的取法中取到了b 那么所有的a都应该被取到,这样才可以保证字典序最小,那么也就是说在26个字母中找到一定要被取的最大字母,然后再确定最大的字母的个数,比它小的全部要取 AC代码: #include &quo…

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…

Given a sequence of K integers { N1, N2, ..., NK }. A continuous subsequence is defined to be { Ni, Ni+1, ..., Nj } where 1 <= i <= j <= K. The Maximum Subsequence is the continuous subsequence which has the largest sum of its elements. For examp…

1​​, N2N_2N​2​​, ..., NKN_KN​K​​ }. A continuous subsequence is defined to be { NiN_iN​i​​, Ni+1N_{i+1}N​i+1​​, ..., NjN_jN​j​​ } where 1≤i≤j≤K1 \le i \le j \le K1≤i≤j≤K. The Maximum Subsequence is the continuous subsequence which has the largest sum…

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…

本题要求在O(n)时间内求解.用delta储存相邻两个数的差,如果相邻的两个delta不同负号,那么说明子序列摇摆了一次.参看下图的nums的plot.这个例子的答案是7.平的线段部分我们支取最左边的一个点.除了最左边的边界点,我们要求delta != 0, 并且newDelta * delta <= 0.(这里不能只取<号),否则dot 5和7就会被忽略,因为他们的newDelta*delta = 0. def wiggleMaxLength(self, nums): ""…

Given an unsorted array of integers, find the length of longest increasing subsequence. For example,Given [10, 9, 2, 5, 3, 7, 101, 18],The longest increasing subsequence is [2, 3, 7, 101], therefore the length is 4. Note that there may be more than o…

3638: Cf172 k-Maximum Subsequence Sum Time Limit: 50 Sec  Memory Limit: 256 MBSubmit: 174  Solved: 92[Submit][Status][Discuss] Description 给一列数,要求支持操作: 1.修改某个数的值 2.读入l,r,k,询问在[l,r]内选不相交的不超过k个子段,最大的和是多少. Input The first line contains integer n (1 ≤ n …

传送门 Description There is a sequence of integers. Your task is to find the longest subsequence that satisfies the following condition: the difference between the maximum element and the minimum element of the subsequence is no smaller than m and no la…

传送门 Description A numeric sequence of ai is ordered if a1 < a2 < ... < aN. Let the subsequence of the given numeric sequence (a1, a2, ..., aN) be any sequence (ai1, ai2, ..., aiK), where 1 <= i1 < i2 < ... < iK <= N. For example, s…

题目链接: 传送门 Subsequence Time Limit: 1000MS     Memory Limit: 65536K 题目描述 给定长度为n的数列整数以及整数S.求出总和不小于S的连续子序列的长度的最小值.如果解不存在,则输出0. 思路 O(nlogn)算法 #include<cstdio> #include<iostream> #include<algorithm> using namespace std; int main() { int T; sca…

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? https://en.wikipedia.org/wiki/Longest_common_subsequence_problem http://baike.…

一个sequence,里面都是整数,求最长的subsequence的长度,使得这个subsquence的最大值和最小值相差不超过1. 比如[1,3,2,2,5,2,3,7]最长的subsequence是[3,2,2,2,3],所以应该返回5. 分析: 这题可以先排序,然后找出两个相差1的相邻值的最大长度.第二种方法可以用HashMap,保存每个值出现的个数,然后从当前值往下找比当前值大1的数出现的个数. public int maxSequence(int[] arr) { ) ; Map<In…

Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array. Formally the function should: Return true if there exists i, j, k such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k ≤ n-1 else return…

题目传送门 题意:输出两字符串的最长公共子序列长度 分析:LCS(Longest Common Subsequence)裸题.状态转移方程:dp[i+1][j+1] = dp[i][j] + 1; (s[i] == t[i])dp[i+1][j+1] = max (dp[i][j+1], dp[i+1][j]); (s[i] != t[i]) 代码: #include <cstdio> #include <cstring> #include <iostream> #in…

题目传送门 题意:LIS(Longest Increasing Subsequence)裸题 分析:状态转移方程:dp[i] = max (dp[j]) + 1   (a[j] < a[i],1 <= j < i) 附带有print输出路径函数 代码: #include <cstdio> #include <algorithm> #include <cstring> using namespace std; const int N = 1e4 + 10…

题目链接:http://acm.hust.edu.cn/vjudge/contest/view.action?cid=87730#problem/F 题目: Description A subsequence of a given sequence is the given sequence with some elements (possible none) left out. Given a sequence X = < x1, x2, ..., xm > another sequence…