前言 这道题的实现方法有很多,包括dp,贪心算法,二分搜索,普通实现等等. 题目 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…

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…

花了将近 20 多天的业余时间,把 LeetCode 上面的题目做完了,毕竟还是针对面试的题目,代码量都不是特别大,难度和 OJ 上面也差了一大截. 关于二叉树和链表方面考察变成基本功的题目特别多,其次是一些简单的动态规划,但是感觉最有意思的还是一些能够在 O(n) 时间内解决的比较 tricky 的题目. 考察对于递归理解的题目也占了一定的比例,更多的时候还是判断一个人在细节方面的领悟程度吧. 没有特别难的题,难的是能一次性的 bug free. 我把代码传到了 https://github.…

Another interesting DP. Lesson learnt: how you define state is crucial.. 1. if DP[i] is defined as, longest wiggle(up\down) subseq AT number i, you will have O(n^2) solution class Solution { struct Rec { Rec(): mlen_dw(), mlen_up(){} Rec(int ldw, int…

版权声明: 本文为博主Bravo Yeung(知乎UserName同名)的原创文章,欲转载请先私信获博主允许,转载时请附上网址 http://blog.csdn.net/lzuacm. Leetcode 65. 有效数字 Leetcode 65. Valid Number 在线提交: Leetcode https://leetcode.com/problems/valid-number/ 类似问题 - PAT 1014_牛客网 https://www.nowcoder.com/pat/6/pro…

Problem 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 Z = <z1, z2, ..., zk> is a subsequence of X if there exists a stri…

Three Sum: Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Note: The solution set must not contain duplicate triplets. 这是一道LeetCode中标记为Medium的…

Question 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 subseq…

题目 查询部门工资前三高的员工. 我用的数据库是oracle. 下面是数据表的信息. Employee表数据: | ID | NAME | Salary | DepartmentId | | -- | ---- | ------ | ------------ | |1 | Joe | 85000 | 1 | |2 | Henry | 80000 | 2 | |3 | Sam | 60000 | 2 | |4 | Max | 90000 | 1 | |5 | Janet | 69000 | 1 |…