03 2018 档案
摘要：Follow up for problem "Populating Next Right Pointers in Each Node". What if the given tree could be any binary tree? Would your previous solution sti
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摘要：Given a binary tree Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL
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摘要：Given two words (beginWord and endWord), and a dictionary's word list, find all shortest transformation sequence(s) from beginWord to endWord, such th
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摘要：Write a function that takes an unsigned integer and returns the number of ’1' bits it has (also known as the Hamming weight). For example, the 32-bit
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摘要：Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest l
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摘要：Given two binary trees, write a function to check if they are the same or not. Two binary trees are considered the same if they are structurally ident
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摘要：You are given coins of different denominations and a total amount of money. Write a function to compute the number of combinations that make up that a
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摘要：9.8 Given an infinite number of quarters (25 cents), dimes (10 cents), nickels (5 cents) and pennies (1 cent), write code to calculate the number of w
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摘要：You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you nee
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摘要：Given an integer array with all positive numbers and no duplicates, find the number of possible combinations that add up to a positive integer target.
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摘要：Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be
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摘要：Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in candidates where the candidate numb
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摘要：Given a set of candidate numbers (candidates) (without duplicates) and a target number (target), find all unique combinations in candidates where the
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摘要：Given a non-empty array of integers, return the k most frequent elements. Example 1: Example 2: Input: nums = [1], k = 1 Output: [1] Example 2: Note:
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摘要：There are N students in a class. Some of them are friends, while some are not. Their friendship is transitive in nature. For example, if A is a direct
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摘要：Given a binary search tree and a node in it, find the in-order successor of that node in the BST. Note: If the given node has no in-order successor in
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摘要：Given a binary tree, return the vertical order traversal of its nodes' values. (ie, from top to bottom, column by column). If two nodes are in the sam
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摘要：Given an Iterator class interface with methods: next() and hasNext(), design and implement a PeekingIterator that support the peek() operation -- it e
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摘要：Given an array nums, there is a sliding window of size k which is moving from the very left of the array to the very right. You can only see the k num
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摘要：Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in-place. Example 1: Example 2: Follow up: A straight forward solu
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摘要：According to the Wikipedia's article: "The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician John
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摘要：Suppose you are at a party with n people (labeled from 0 to n - 1) and among them, there may exist one celebrity. The definition of a celebrity is tha
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摘要：Given a binary tree, you need to compute the length of the diameter of the tree. The diameter of a binary tree is the length of the longest path betwe
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摘要：Given a non-empty string check if it can be constructed by taking a substring of it and appending multiple copies of the substring together. You may a
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摘要：Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array. Example 1 Example 2 Note:Your al
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摘要：Reverse bits of a given 32 bits unsigned integer. For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), retur
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摘要：Follow up for H-Index: What if the citations array is sorted in ascending order? Could you optimize your algorithm? Hint: 274. H-Index H指数 的拓展。输入的数组是有
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摘要：Given an array of citations (each citation is a non-negative integer) of a researcher, write a function to compute the researcher's h-index. According
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摘要：Given a string, find the first non-repeating character in it and return it's index. If it doesn't exist, return -1. Examples: Note: You may assume the
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摘要：Given two non-negative numbers num1 and num2 represented as string, return the sum of num1 and num2. Note: 两个只含有数字的字符串相加。 解法: 对于每个字符转成对应的整数，然后相加，结果在写入
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摘要：Given an array of integers, find out whether there are two distinct indices i and j in the array such that the absolute difference between nums[i] and
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摘要：Given an array of integers and an integer k, find out whether there are two distinct indices i and j in the array such that nums[i] = nums[j] and the
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摘要：Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in the arr
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摘要：The thief has found himself a new place for his thievery again. There is only one entrance to this area, called the "root." Besides the root, each hou
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摘要：Note: This is an extension of House Robber. After robbing those houses on that street, the thief has found himself a new place for his thievery so tha
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摘要：You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping yo
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摘要：Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in or
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摘要：Given an array, rotate the array to the right by k steps, where k is non-negative. Example 1: Example 2: Note: Try to come up as many solutions as you
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摘要：Compare two version numbers version1 and version1.If version1 > version2 return 1, if version1 < version2 return -1, otherwise return 0. You may assum
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摘要：You are a product manager and currently leading a team to develop a new product. Unfortunately, the latest version of your product fails the quality c
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摘要：Given an index k, return the kth row of the Pascal's triangle. For example, given k = 3,Return [1,3,3,1]. Note:Could you optimize your algorithm to us
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摘要：Given numRows, generate the first numRows of Pascal's triangle. For example, given numRows = 5,Return 杨辉三角形，又称贾宪三角形、帕斯卡三角形、海亚姆三角形、巴斯卡三角形，是二项式系数在的一种写法，
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摘要：Given a non-empty binary search tree and a target value, find k values in the BST that are closest to the target. Note: Given target value is a floati
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摘要：Given a non-empty binary search tree and a target value, find the value in the BST that is closest to the target. Note: Given target value is a floati
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摘要：Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to check whether these edges mak
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摘要：Given an array of scores that are non-negative integers. Player 1 picks one of the numbers from either end of the array followed by the player 2 and t
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摘要：We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wron
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摘要：We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wron
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摘要：转自： only_on_one 前天参加58集团笔试，最后的问答题有一道这样的题，事后推敲后觉得很有意思，就记录下来吧。 给定100个乒乓球，甲乙两人轮流拿，每人每次最少拿1个，最多拿6个，问有没有必胜的拿法，如有，哪方必胜？ 答：有必胜的方法，先拿的必胜。通过列举法找到规律： 从上述规律可以看出，
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摘要：我写的Python代码： class Solution(object): def getNumberGame(self, n, nums): m = len(nums) dp = [[0] * m for j in xrange(m)] for i in xrange(m): dp[i][i] =
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摘要：Given a string, determine if a permutation of the string could form a palindrome. For example,"code" -> False, "aab" -> True, "carerac" -> True. Hint:
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摘要：Given a string s, return all the palindromic permutations (without duplicates) of it. Return an empty list if no palindromic permutation could be form
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摘要：Remove all elements from a linked list of integers that have value val. ExampleGiven: 1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6, val = 6Return: 1 --> 2 --
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摘要：Given a linked list, remove the nth node from the end of list and return its head. For example, Note:Given n will always be valid.Try to do this in on
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摘要：Given an array nums and a value val, remove all instances of that value in-place and return the new length. Do not allocate extra space for another ar
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摘要：Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted i
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摘要：Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted f
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摘要：There are a number of spherical balloons spread in two-dimensional space. For each balloon, provided input is the start and end coordinates of the hor
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摘要：Given n balloons, indexed from 0 to n-1. Each balloon is painted with a number on it represented by array nums. You are asked to burst all the balloon
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摘要：Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: All root-to-leaf paths are: 给一个二叉树，返回所有根到叶节点的路径。 Jav
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摘要：Given a linked list, swap every two adjacent nodes and return its head. For example,Given 1->2->3->4, you should return the list as 2->1->4->3. Your a
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摘要：Given a non-empty string s, you may delete at most one character. Judge whether you can make it a palindrome. Example 1: Example 2: Note: 125. Valid P
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摘要：Given a singly linked list, determine if it is a palindrome. Follow up:Could you do it in O(n) time and O(1) space? 给一个链表，判断是否为回文。 如果是字符串就比较容易判断。但链表不能
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摘要：Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as: a binary tree in which the dep
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摘要：You are asked to cut off trees in a forest for a golf event. The forest is represented as a non-negative 2D map, in this map: You are asked to cut off
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摘要：The Fibonacci numbers are the numbers in the following integer sequence. 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, …….. In mathematical terms, the
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摘要：Design a simplified version of Twitter where users can post tweets, follow/unfollow another user and is able to see the 10 most recent tweets in the u
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摘要：Given a 2D board and a list of words from the dictionary, find all words in the board. Each word must be constructed from letters of sequentially adja
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摘要：Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. For example, given the following ma
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摘要：Given an absolute path for a file (Unix-style), simplify it. For example,path = "/home/", => "/home"path = "/a/./b/../../c/", => "/c" Corner Cases: Di
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摘要：Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST. Calling next() will return the n
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摘要：Given a linked list, return the node where the cycle begins. If there is no cycle, return null. Follow up:Can you solve it without using extra space?
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摘要：Given a linked list, determine if it has a cycle in it. Follow up:Can you solve it without using extra space? 给定一个链表，判断是否有环存在。Follow up: 不使用额外空间。 解法：双
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摘要：Write a program to find the node at which the intersection of two singly linked lists begins. For example, the following two linked lists: begin to in
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摘要：Given two strings S and T, determine if they are both one edit distance apart. 72. Edit Distance 的类似题目，编辑距离是从一个单词变成另一个单词的变换步骤。变换步骤可以是：插入，删除和替换。所以考虑三种情
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摘要：Given two words word1 and word2, find the minimum number of operations required to convert word1 to word2. You have the following 3 operations permitt
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摘要：A peak element is an element that is greater than its neighbors. Given an input array where num[i] ≠ num[i+1], find a peak element and return its inde
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摘要：Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times. You may assume that the
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摘要：Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example: Cr
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摘要：Given a positive integer, return its corresponding column title as appear in an Excel sheet. For example: Credits:Special thanks to @ifanchu for addin
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摘要：Given two strings s and t , write a function to determine if t is an anagram of s. Example 1: Input: s = "anagram", t = "nagaram" Output: true Example
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摘要：Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level from leaf to root). For
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摘要：Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for the next level and
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摘要：Given a binary search tree, write a function kthSmallest to find the kth smallest element in it. Note: You may assume k is always valid, 1 ≤ k ≤ BST's
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摘要：If the depth of a tree is smaller than 5, then this tree can be represented by a list of three-digits integers. For each integer in this list: Given a
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摘要：You are given a binary tree in which each node contains an integer value. Find the number of paths that sum to a given value. The path does not need t
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摘要：Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example:Given the below binary tree and sum
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摘要：Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. F
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摘要：Given a 2D board and a word, find if the word exists in the grid. The word can be constructed from letters of sequentially adjacent cell, where "adjac
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摘要：Given a collection of integers that might contain duplicates, nums, return all possible subsets (the power set). Note: The solution set must not conta
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摘要：Given a set of distinct integers, nums, return all possible subsets (the power set). Note: The solution set must not contain duplicate subsets. For ex
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摘要：Given an array of words and a length L, format the text such that each line has exactly L characters and is fully (left and right) justified. You shou
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摘要：Implement int sqrt(int x). Compute and return the square root of x. 求一个数的平方根。 解法：二分法，迭代循环在x范围内找中间值mid，然后判断mid * mid和x，如果mid > x/mid（不要写成middle*middle=
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摘要：Given an array of n integers where n > 1, nums, return an array output such that output[i] is equal to the product of all the elements of nums except
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摘要：Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. According to the definition of LCA on Wikipedia: “The lowes
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摘要：Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia
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摘要：Given n points on a 2D plane, find the maximum number of points that lie on the same straight line. 给一个由n个点组成的2D平面，找出最多的同在一条直线上的点的个数。 共线点的条件是斜率一样，corn
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摘要：Implement an iterator to flatten a 2d vector. For example,Given 2d vector = By calling next repeatedly until hasNext returns false, the order of eleme
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摘要：Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), find the minimum number of conference room
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摘要：Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), determine if a person could attend all mee
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摘要：Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integ
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摘要：Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary tree is symmetric: But the fol
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摘要：Write an algorithm to determine if a number is "happy". A happy number is a number defined by the following process: Starting with any positive intege
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摘要：Write a function to delete a node (except the tail) in a singly linked list, given only access to that node. Given linked list -- head = [4,5,1,9], wh
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摘要：Given a string which contains only lowercase letters, remove duplicate letters so that every letter appear once and only once. You must make sure your
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摘要：Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list. For example,Given 1->2
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摘要：Given a sorted linked list, delete all duplicates such that each element appear only once. Example 1: Example 2: 移除有序链表中的重复项，返回新链表。定义1个指针指向链表的第一个元素，然后
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摘要：Given a sorted array nums, remove the duplicates in-place such that duplicates appeared at most twice and return the new length. Do not allocate extra
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摘要：Given a sorted array nums, remove the duplicates in-place such that each element appear only once and return the new length. Do not allocate extra spa
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摘要：Given an integer n, generate a square matrix filled with elements from 1 to n^2 in spiral order. For example,Given n = 3, You should return the follow
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摘要：Given a matrix of m x n elements (m rows, n columns), return all elements of the matrix in spiral order. For example,Given the following matrix: You s
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摘要：You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note: You have to rotate the image in-place, which
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摘要：Determine if a 9x9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules: A partially filled sudoku which
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摘要：Implement strStr(). Return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. Example 1: Example 2: 在一个
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摘要：Implement pow(x, n). 求x的n次幂，如果用n个循环相乘，那就太简单了，肯定不是这题要考察的。 解法：利用性质： n是奇数，n % 2 == 1, x^n = x^(n/2) * x^(n/2) * x;n是偶数，n % 2 == 0, x^n = x^(n/2) * x^(n/2
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摘要：Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000. Example 1:Input: Output
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摘要：Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Pan
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摘要：Given a binary tree, find its maximum depth. The maximum depth is the number of nodes along the longest path from the root node down to the farthest l
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摘要：The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order,We get the following sequence
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摘要：Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrangement is not possib
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摘要：Given a collection of numbers that might contain duplicates, return all possible unique permutations. For example,[1,1,2] have the following unique pe
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摘要：Given a collection of numbers, return all possible permutations. For example,[1,2,3] have the following permutations:[1,2,3], [1,3,2], [2,1,3], [2,3,1
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摘要：Given two integers n and k, return all possible combinations of k numbers out of 1 ... n. For example,If n = 4 and k = 2, a solution is: 给两个数字n, k，返回所
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摘要：Description: Count the number of prime numbers less than a non-negative number, n click to show more hints. References: How Many Primes Are There? Sie
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摘要：A binary watch has 4 LEDs on the top which represent the hours (0-11), and the 6 LEDs on the bottom represent the minutes (0-59). Each LED represents
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摘要：Convert a non-negative integer to its english words representation. Given input is guaranteed to be less than 231 - 1. Example 1: Example 2: Example 3
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摘要：What happens when you type an URL in the browser and press enter? 1. You type maps.google.com into the address bar of your browser. 2. The browser che
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摘要：HTTP Status Codes 1xx Informational 100 Continue 101 Switching Protocols 102 Processing (WebDAV) 2xx Success 200 OK 201 Created 202 Accepted 203 Non-A
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摘要：Binary Search: Search a sorted array by repeatedly dividing the search interval in half. Begin with an interval covering the whole array. If the value
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摘要：What is the difference between POST and GET HTTP requests? GET and POST are two different types of HTTP requests. According to Wikipedia: GET requests
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摘要：Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum. Example: Foll
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摘要：Given a char array representing tasks CPU need to do. It contains capital letters A to Z where different letters represent different tasks.Tasks could
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摘要：Given a non-empty string str and an integer k, rearrange the string such that the same characters are at least distance k from each other. All input s
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摘要：Given n, generate all structurally unique BST's (binary search trees) that store values 1...n. For example,Given n = 3, your program should return all
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摘要：Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST'
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摘要：Given an array of strings, group anagrams together. For example, given: ["eat", "tea", "tan", "ate", "nat", "bat"], Return: Note: All inputs will be i
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摘要：Follow up for "Find Minimum in Rotated Sorted Array":What if duplicates are allowed? Would this affect the run-time complexity? How and why? Suppose a
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摘要：Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find
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摘要：Follow up for "Search in Rotated Sorted Array":What if duplicates are allowed? Would this affect the run-time complexity? How and why? Suppose an arra
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摘要：Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). You are given a target va
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摘要：Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order. E
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摘要：Given an input string, reverse the string word by word. A word is defined as a sequence of non-space characters.The input string does not contain lead
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摘要：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 pr
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摘要：Given a string, find the length of the longest substring T that contains at most k distinct characters. For example, Given s = “eceba” and k = 2, T is
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摘要：Given two words (beginWord and endWord), and a dictionary's word list, find the length of shortest transformation sequence from beginWord to endWord,
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摘要：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 inc
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摘要：You have a number of envelopes with widths and heights given as a pair of integers (w, h). One envelope can fit into another if and only if both the w
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摘要：A city's skyline is the outer contour of the silhouette formed by all the buildings in that city when viewed from a distance. Now suppose you are give
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摘要：Given an m x n matrix of positive integers representing the height of each unit cell in a 2D elevation map, compute the volume of water it is able to
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摘要：Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may comple
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摘要：Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may comple
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摘要：Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may comple
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摘要：Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may comple
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摘要：Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction
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摘要：There is a new alien language which uses the latin alphabet. However, the order among letters are unknown to you. You receive a list of words from the
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摘要：There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites, for example to take course 0 you have t
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摘要：There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites, for example to take course 0 you have t
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摘要：Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue. pop() -- Removes the element from in front
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摘要：Implement the following operations of a stack using queues. push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. to
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摘要：Given a string S, find the length of the longest substring T that contains at most two distinct characters.For example,Given S = "eceba",T is "ece" wh
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摘要：Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n). For example,S = "ADOBECOD
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摘要：Implement a trie with insert, search, and startsWith methods. Example: Note: You may assume that all inputs are consist of lowercase letters a-z. All
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摘要：Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tree {3
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摘要：Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element. Example
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摘要：Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity. Example: 与21. Merge Two Sorted Lists的拓展，这道题要合并k个有序链
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摘要：Design and implement a data structure for Least Recently Used (LRU) cache. It should support the following operations: get and set. get(key) - Get the
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摘要：Design a data structure that supports all following operations in average O(1) time. Note: Duplicate elements are allowed. Example: 380. Insert Delete
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摘要：Design a data structure that supports all following operations in average O(1) time. Example: 设计一个数据结构在O(1)时间内完成：insert(val)，remove(val)，getRandom() 由
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摘要：Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary). You may assume that the intervals were initia
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摘要：Given a collection of intervals, merge all overlapping intervals. Example 1: Example 2: 给定一个有重叠的区间集合，合并所有重叠的区间。先对区间以第一个元素进行排序，定义一个变量result记录合并后的区间。然后迭
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摘要：Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) -- Push element x onto stack. pop() -- Remov
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摘要：Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, determine if s can be segmented into a space-separated sequ
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摘要：Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, add spaces in s to construct a sentence where each word is
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摘要：Serialization is the process of converting a data structure or object into a sequence of bits so that it can be stored in a file or memory buffer, or
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摘要：Reverse a singly linked list. Hint: A linked list can be reversed either iteratively or recursively. Could you implement both? 反向链表，分别用递归和迭代方式实现。 递归It
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摘要：Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2-
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摘要：Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. For example: Given num = 38, the process is like:
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摘要：Given a non-empty array of digits representing a non-negative integer, plus one to the integer. The digits are stored such that the most significant d
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摘要：Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists. Example:
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摘要：Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array. Note: The number of elements initialized in nums1 and num
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摘要：Given an input string (s) and a pattern (p), implement regular expression matching with support for '.' and '*'. The matching should cover the entire
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摘要：Implement wildcard pattern matching with support for '?' and '*'. 通配符匹配问题，和10. Regular Expression Matching 类似。'?'匹配1个字符，'*'匹配任何字符序列，包括空的。有贪心Greedy， 动态
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摘要：Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses. For example, given n = 3, a solution set is: "
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摘要：Given a string containing just the characters '(' and ')', find the length of the longest valid (well-formed) parentheses substring. Example 1: Exampl
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摘要：Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. An input string is valid if: No
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摘要：Given four lists A, B, C, D of integer values, compute how many tuples (i, j, k, l) there are such that A[i] + B[j] + C[k] + D[l] is zero. To make pro
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摘要：Given an array nums of n integers and an integer target, are there elements a, b, c, and d in nums such that a + b + c + d = target? Find all unique q
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摘要：Given an array nums, write a function to move all 0's to the end of it while maintaining the relative order of the non-zero elements. For example, giv
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摘要：Given a digit string, return all possible letter combinations that the number could represent. A mapping of digit to letters (just like on the telepho
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摘要：Given n non-negative integers a1, a2, ..., an, where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpo
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摘要：Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining.
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摘要：Write a function to find the longest common prefix string amongst an array of strings. If there is no common prefix, return an empty string "". Exampl
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摘要：Given an array nums of n integers and an integer target, find three integers in nums such that the sum is closest to target. Return the sum of the thr
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摘要：Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the s
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摘要：Given an array with n objects colored red, white or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the or
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摘要：Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. For example, two is written as II in Roman numeral, just two one's
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摘要：Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. For example, two is written as II in Roman numeral, just two one's
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