09 2015 档案

Path Sum II 解答
摘要：QuestionGiven 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 ... 阅读全文
posted @ 2015-09-30 23:24 树獭君 阅读(127) 评论(0) 推荐(0)
Path Sum 解答
摘要：QuestionGiven 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 give... 阅读全文
posted @ 2015-09-30 22:52 树獭君 阅读(166) 评论(0) 推荐(0)
Binary Tree Paths 解答
摘要：QuestionGiven a binary tree, return all root-to-leaf paths.For example, given the following binary tree: 1 / \2 3 \ 5All root-to-leaf paths a... 阅读全文
posted @ 2015-09-30 05:00 树獭君 阅读(192) 评论(0) 推荐(0)
Populating Next Right Pointers in Each Node 解答
摘要：QuestionGiven a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; }Populate each nex... 阅读全文
posted @ 2015-09-29 10:38 树獭君 阅读(190) 评论(0) 推荐(0)
Validate Binary Search Tree 解答
摘要：QuestionGiven a binary tree, determine if it is a valid binary search tree (BST).Assume a BST is defined as follows:The left subtree of a node contain... 阅读全文
posted @ 2015-09-29 09:27 树獭君 阅读(157) 评论(0) 推荐(0)
Binary Tree Inorder Traversal
摘要：(referrence: ProgramCreek)The key to solve inorder traversal of binary tree includes the following:The order of "inorder" is: left child -> parent -> ... 阅读全文
posted @ 2015-09-29 08:43 树獭君 阅读(220) 评论(0) 推荐(0)
Course Schedule 解答
摘要：QuestionThere are a total ofncourses you have to take, labeled from0ton - 1.Some courses may have prerequisites, for example to take course 0 you have... 阅读全文
posted @ 2015-09-29 07:19 树獭君 阅读(249) 评论(0) 推荐(0)
Topological Sorting
摘要：Topological sorting/ ordering is a linear ordering of itsverticessuch that for every directed edgeuvfrom vertexuto vertexv,ucomes beforevin the orderi... 阅读全文
posted @ 2015-09-28 23:05 树獭君 阅读(566) 评论(0) 推荐(0)
Maximum Depth of Binary Tree 解答
摘要：Question 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 f 阅读全文
posted @ 2015-09-24 10:17 树獭君 阅读(134) 评论(0) 推荐(0)
Clone Graph 解答
摘要：QuestionClone an undirected graph. Each node in the graph contains alabeland a list of itsneighbors.OJ's undirected graph serialization:Nodes are labe... 阅读全文
posted @ 2015-09-24 10:07 树獭君 阅读(198) 评论(0) 推荐(0)
Java Keyword -- super
摘要：Reference: superWhen we override superclass's methods, but still want to invoke them, we can use keyword super in child classes.We can also usesuperto... 阅读全文
posted @ 2015-09-24 08:38 树獭君 阅读(179) 评论(0) 推荐(0)
Binary Tree Zigzag Level Order Traversal 解答
摘要：QuestionGiven a binary tree, return thezigzag level ordertraversal of its nodes' values. (ie, from left to right, then right to left for the next leve... 阅读全文
posted @ 2015-09-24 07:04 树獭君 阅读(175) 评论(0) 推荐(0)
Minimum Depth of Binary Tree 解答
摘要：QuestionGiven 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 ne... 阅读全文
posted @ 2015-09-24 05:39 树獭君 阅读(155) 评论(0) 推荐(0)
Binary Tree Level Order Traversal II 解答
摘要：QuestionGiven a binary tree, return thebottom-up level ordertraversal of its nodes' values. (ie, from left to right, level by level from leaf to root)... 阅读全文
posted @ 2015-09-24 04:58 树獭君 阅读(176) 评论(0) 推荐(0)
Binary Tree Level Order Traversal 解答
摘要：Question Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binar 阅读全文
posted @ 2015-09-24 04:47 树獭君 阅读(194) 评论(0) 推荐(0)
BFS visit tree
摘要：There are two ways to conduct BFS on tree.Solution 1 -- Given levelUse recursion to find given level, and print./*Function to print level order traver... 阅读全文
posted @ 2015-09-24 04:18 树獭君 阅读(303) 评论(0) 推荐(0)
Kth Largest Element in an Array 解答
摘要：QuestionFind thekth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element.Fo... 阅读全文
posted @ 2015-09-22 07:24 树獭君 阅读(718) 评论(0) 推荐(0)
Merge k Sorted Lists 解答
摘要：QuestionMergeksorted linked lists and return it as one sorted list. Analyze and describe its complexity.Solution 1 -- Merge SortWe can follow the meth... 阅读全文
posted @ 2015-09-22 04:53 树獭君 阅读(147) 评论(0) 推荐(0)
Median of Two Sorted Arrays 解答
摘要：QuestionThere are two sorted arraysnums1andnums2of size m and n respectively. Find the median of the two sorted arrays. The overall run time complexit... 阅读全文
posted @ 2015-09-22 03:03 树獭君 阅读(203) 评论(0) 推荐(0)
Maximal Square 解答
摘要：QuestionGiven a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area.For example, given the follow... 阅读全文
posted @ 2015-09-21 08:40 树獭君 阅读(165) 评论(0) 推荐(0)
Best Time to Buy and Sell Stock III 解答
摘要：QuestionSay you have an array for which theithelement is the price of a given stock on dayi.Design an algorithm to find the maximum profit. You may co... 阅读全文
posted @ 2015-09-21 07:23 树獭君 阅读(150) 评论(0) 推荐(0)
Best Time to Buy and Sell Stock II 解答
摘要：QuestionSay you have an array for which theithelement is the price of a given stock on dayi.Design an algorithm to find the maximum profit. You may co... 阅读全文
posted @ 2015-09-21 05:39 树獭君 阅读(172) 评论(0) 推荐(0)
Best Time to Buy and Sell Stock 解答
摘要：QuestionSay you have an array for which theithelement is the price of a given stock on dayi.If you were only permitted to complete at most one transac... 阅读全文
posted @ 2015-09-21 03:47 树獭君 阅读(203) 评论(0) 推荐(0)
Triangle 解答
摘要：QuestionGiven a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.For example, given... 阅读全文
posted @ 2015-09-21 03:30 树獭君 阅读(231) 评论(0) 推荐(0)
Unique Binary Search Trees II 解答
摘要：QuestionGivenn, generate all structurally uniqueBST's(binary search trees) that store values 1...n.For example,Givenn= 3, your program should return a... 阅读全文
posted @ 2015-09-21 02:36 树獭君 阅读(171) 评论(0) 推荐(0)
Unique Binary Search Trees 解答
摘要：QuestionGivenn, how many structurally uniqueBST's(binary search trees) that store values 1...n?For example,Givenn= 3, there are a total of 5 unique BS... 阅读全文
posted @ 2015-09-20 07:46 树獭君 阅读(127) 评论(0) 推荐(0)
Unique Paths II 解答
摘要：QuestionFollow up for "Unique Paths":Now consider if some obstacles are added to the grids. How many unique paths would there be?An obstacle and empty... 阅读全文
posted @ 2015-09-20 03:04 树獭君 阅读(135) 评论(0) 推荐(0)
Unique Paths 解答
摘要：QuestionA robot is located at the top-left corner of amxngrid (marked 'Start' in the diagram below).The robot can only move either down or right at an... 阅读全文
posted @ 2015-09-20 02:41 树獭君 阅读(142) 评论(0) 推荐(0)
Maximum Subarray 解答
摘要：QuestionFind the contiguous subarray within an array (containing at least one number) which has the largest sum.For example, given the array[−2,1,−3,4... 阅读全文
posted @ 2015-09-20 02:26 树獭君 阅读(179) 评论(0) 推荐(0)
Climbing Stairs 解答
摘要：QuestionYou are climbing a stair case. It takesnsteps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can y... 阅读全文
posted @ 2015-09-19 23:46 树獭君 阅读(213) 评论(0) 推荐(0)
House Robber II 解答
摘要：QuestionAfter robbing those houses on that street, the thief has found himself a new place for his thievery so that he will not get too much attention... 阅读全文
posted @ 2015-09-19 23:33 树獭君 阅读(155) 评论(0) 推荐(0)
House Robber 解答
摘要：QuestionYou are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint sto... 阅读全文
posted @ 2015-09-19 23:05 树獭君 阅读(199) 评论(0) 推荐(0)
Valid Palindrome 解答
摘要：QuestionGiven a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.For example,"A man, a plan, a can... 阅读全文
posted @ 2015-09-17 08:05 树獭君 阅读(170) 评论(0) 推荐(0)
Container With Most Water 解答
摘要：QuestionGivennnon-negative integersa1,a2, ...,an, where each represents a point at coordinate (i,ai).nvertical lines are drawn such that the two endpo... 阅读全文
posted @ 2015-09-17 03:46 树獭君 阅读(140) 评论(0) 推荐(0)
Remove Duplicates from Sorted List II 解答
摘要：QuestionGiven a sorted linked list, delete all nodes that have duplicate numbers, leaving onlydistinctnumbers from the original list.For example,Given... 阅读全文
posted @ 2015-09-16 22:59 树獭君 阅读(135) 评论(0) 推荐(0)
Intersection of Two Linked Lists 解答
摘要：QuestionWrite a program to find the node at which the intersection of two singly linked lists begins.For example, the following two linked lists:A: ... 阅读全文
posted @ 2015-09-16 10:45 树獭君 阅读(191) 评论(0) 推荐(0)
Merge Two Sorted Lists 解答
摘要：QuestionMerge 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.S... 阅读全文
posted @ 2015-09-16 09:03 树獭君 阅读(123) 评论(0) 推荐(0)
Remove Nth Node From End of List 解答
摘要：QuestionGiven a linked list, remove thenthnode from the end of list and return its head.For example, Given linked list: 1->2->3->4->5, and n = 2. ... 阅读全文
posted @ 2015-09-16 06:09 树獭君 阅读(177) 评论(0) 推荐(0)
Reverse Linked List 解答
摘要：QuestionReverse a singly linked list.Solution 1 -- IterativeRemember to set head.next = null or it will report "memory limit exceeds" error. 1 /** 2 ... 阅读全文
posted @ 2015-09-16 03:17 树獭君 阅读(196) 评论(0) 推荐(0)
Longest Substring Without Repeating Characters 解答
摘要：QuestionGiven a string, find the length of the longest substring without repeating characters. For example, the longest substring without repeating le... 阅读全文
posted @ 2015-09-16 01:55 树獭君 阅读(112) 评论(0) 推荐(0)
Repeated DNA Sequences 解答
摘要：QuestionAll DNA is composed of a series of nucleotides abbreviated as A, C, G, and T, for example: "ACGAATTCCG". When studying DNA, it is sometimes us... 阅读全文
posted @ 2015-09-15 06:05 树獭君 阅读(216) 评论(0) 推荐(0)
Minimum Size Subarray Sum 解答
摘要：QuestionGiven an array ofnpositive integers and a positive integers, find the minimal length of a subarray of which the sum ≥s. If there isn't one, re... 阅读全文
posted @ 2015-09-15 04:45 树獭君 阅读(133) 评论(0) 推荐(0)
Single Number 解答
摘要：QuestionGiven an array of integers, every element appearstwiceexcept for one. Find that single one.Solution 1 -- SetWe can use a hash set to record ea... 阅读全文
posted @ 2015-09-15 04:45 树獭君 阅读(164) 评论(0) 推荐(0)
Valid Anagram 解答
摘要：QuestionGiven two stringssandt, write a function to determine iftis an anagram ofs.For example,s= "anagram",t= "nagaram", return true.s= "rat",t= "car... 阅读全文
posted @ 2015-09-15 02:04 树獭君 阅读(184) 评论(0) 推荐(0)
Count Primes 解答
摘要：QuestionCount the number of prime numbers less than a non-negative number,n.Solution 1Naive way, to check each number one by one. If a number i is pri... 阅读全文
posted @ 2015-09-14 06:44 树獭君 阅读(204) 评论(0) 推荐(0)
Isomorphic Strings 解答
摘要：QuestionGiven two stringssandt, determine if they are isomorphic.Two strings are isomorphic if the characters inscan be replaced to gett.All occurrenc... 阅读全文
posted @ 2015-09-14 04:43 树獭君 阅读(181) 评论(0) 推荐(0)
Search Insert Position 解答
摘要：QuestionGiven 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 insert... 阅读全文
posted @ 2015-09-14 02:10 树獭君 阅读(152) 评论(0) 推荐(0)
Sort Colors 解答
摘要：QuestionGiven an array withnobjects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order... 阅读全文
posted @ 2015-09-12 00:56 树獭君 阅读(159) 评论(0) 推荐(0)
Contains Duplicate II 解答
摘要：QuestionGiven an array of integers and an integerk, find out whether there are two distinct indicesiandjin the array such thatnums[i] = nums[j]and the... 阅读全文
posted @ 2015-09-11 23:26 树獭君 阅读(152) 评论(0) 推荐(0)
Pascal's Triangle II 解答
摘要：QuestionGiven an indexk, return thekthrow of the Pascal's triangle.For example, givenk= 3,Return[1,3,3,1].SolutionSimilar with Pascal's Triangle. Note... 阅读全文
posted @ 2015-09-11 23:06 树獭君 阅读(220) 评论(0) 推荐(0)
Pascal's Triangle 解答
摘要：QuestionGivennumRows, generate the firstnumRowsof Pascal's triangle.For example, givennumRows= 5,Return[ [1], [1,1], [1,2,1], [1,3,3,1], [1,... 阅读全文
posted @ 2015-09-11 08:47 树獭君 阅读(374) 评论(0) 推荐(0)
Summary Ranges 解答
摘要：QuestionGiven a sorted integer array without duplicates, return the summary of its ranges.For example, given[0,1,2,4,5,7], return["0->2","4->5","7"].S... 阅读全文
posted @ 2015-09-11 07:56 树獭君 阅读(165) 评论(0) 推荐(0)
Remove Element 解答
摘要：QuestionGiven an array and a value, remove all instances of that value in place and return the new length.The order of elements can be changed. It doe... 阅读全文
posted @ 2015-09-11 05:51 树獭君 阅读(133) 评论(0) 推荐(0)
Remove Duplicates from Sorted Array 解答
摘要：QuestionGiven a sorted array, remove the duplicates in place such that each element appear onlyonceand return the new length.Do not allocate extra spa... 阅读全文
posted @ 2015-09-11 05:42 树獭君 阅读(148) 评论(0) 推荐(0)
Rotate Array 解答
摘要：QuestionRotate an array ofnelements to the right byksteps.For example, withn= 7 andk= 3, the array[1,2,3,4,5,6,7]is rotated to[5,6,7,1,2,3,4].Solution... 阅读全文
posted @ 2015-09-11 05:19 树獭君 阅读(181) 评论(0) 推荐(0)
Plus One 解答
摘要：QuestionGiven a non-negative number represented as an array of digits, plus one to the number.The digits are stored such that the most significant dig... 阅读全文
posted @ 2015-09-11 04:24 树獭君 阅读(173) 评论(0) 推荐(0)
Contains Duplicate 解答
摘要：QuestionGiven an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in... 阅读全文
posted @ 2015-09-11 04:03 树獭君 阅读(150) 评论(0) 推荐(0)
Merge Sorted Array 解答
摘要：QuestionGiven two sorted integer arraysnums1andnums2, mergenums2intonums1as one sorted array.Note:You may assume thatnums1has enough space (size that ... 阅读全文
posted @ 2015-09-11 03:53 树獭君 阅读(189) 评论(0) 推荐(0)
Majority Element 解答
摘要：Solution 1Naive wayFirst, sort the array using Arrays.sort in Java. Than, scan once to find the majority element. Time complexity O(nlog(n)) 1 public ... 阅读全文
posted @ 2015-09-11 03:07 树獭君 阅读(171) 评论(0) 推荐(0)
Two Sum 解答
摘要：Question: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 t... 阅读全文
posted @ 2015-09-01 10:52 树獭君 阅读(231) 评论(0) 推荐(0)