Difficulty: Hard  More:[目录]LeetCode Java实现 Description Validate if a given string can be interpreted as a decimal number. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10&qu…

Validate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => true 解决方案: public class Solution { public boolean isNumber(String s) { in…

Question: Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example, "A man, a plan, a canal: Panama" is a palindrome. "race a car" is not a palindrome.Example Questions C…

因为最近一段时间接触了一些Leetcode上的题目,发现许多题目的解题思路相似,从中其实可以了解某类算法的一些应用场景. 这个随笔系列就是我尝试的分析总结,希望也能给大家一些启发. 动态规划的基本概念 一言以蔽之,动态规划就是将大问题分成小问题,以迭代的方式求解. 可以使用动态规划求解的问题一般有如下的两个特征: 1.有最优子结构(optimal substructure) 即待解决问题的最优解能够通过求解子问题的最优解得到. 2.子问题间有重叠(overlapping subproplems)…

Question: Find the contiguous subarray within an array (containing at least one number) that has the largest sum. For example, given the array [2, 1, –3, 4, –1, 2, 1, –5, 4], The contiguous array [4, –1, 2, 1] has the largest sum = 6. 此问题提供了两种解决方案,首先…

Leetcode里面关于字符串的一些问题,描述如下: Given an input string, reverse the string word by word. For example,Given s = "the sky is blue",return "blue is sky the". Update (2015-02-12):For C programmers: Try to solve it inO(1) space. click to show cla…

一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Validate if a given string is numeric. Some examples: "0" => true " 0.1 " => true "abc" => false "1 a" => fals…

Validate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => true 基本上是leetCode上通过率最低的一道了,自己写了很多遍,就是有小问题通不过,最后参考了别人的写法,很精简,代码如下所示: bool…

Given string S and a dictionary of words words, find the number of words[i] that is a subsequence of S. Example : Input: S = "abcde" words = ["a", "bb", "acd", "ace"] Output: 3 Explanation: There are three…

问题描述: 在股市的交易日中,假设最多可进行两次买卖(即买和卖的次数均小于等于2),规则是必须一笔成交后进行另一笔(即买-卖-买-卖的顺序进行).给出一天中的股票变化序列,请写一个程序计算一天可以获得的最大收益.请采用实践复杂度低的方法实现. 给定价格序列prices及它的长度n,请返回最大收益.保证长度小于等于500. class Solution { public: int maxProfit(vector<int>& prices) { //It's wrong if you c…