Given a string S, find the longest palindromic substring in S. You may assume that the maximum length of S is 1000, and there exists one unique longest palindromic substring. Tags: String 容易想到的思路(可以解但会超时): class Solution { public: string longestPalin…
Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors. OJ's undirected graph serialization: Nodes are labeled uniquely. We use # as a separator for each node, and , as a separator for node label and each neigh…
Reverse digits of an integer. Example1: x = 123, return 321Example2: x = -123, return -321 click to show spoilers. Have you thought about this? Here are some good questions to ask before coding. Bonus points for you if you have already thought throug…
The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I RAnd then read line by line: "PAHNAPLSIIG…
There are two sorted arrays A and B of size m and n respectively. Find the median of the two sorted arrays. The overall run time complexity should be O(log (m+n)). Tags: Divide and Conquer, Array, Binary Search 分析: 对于数字个数k,如果k为奇数,则k个数的中位数为第(k/2+1)个:对…
Given a string, find the length of the longest substring without repeating characters. For example, the longest substring without repeating letters for "abcabcbb" is "abc", which the length is 3. For "bbbbb" the longest subst…
You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list. Input: (2 -> 4 -> 3) + (5 -> 6 ->…
Given an array of integers, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2. Please note that…
August 2, 2015 在http://zzk.cnblogs.com/ 用"找一找", 花了几个小时, 找出比较好的Leetcode博客． Read the leetcode question and solutions: 1. Find lowest common ancestor in binary tree: blog of a facebook programmer working on leetcode questions: 递归版本:空间O(1),时间O(n) ht…
