猪猪🐷 - 博客园

221. Maximal Square

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. Example: Input: 1 0 1 0 0 1 0 1 1 1 阅读全文

posted @ 2018-08-11 03:32 猪猪🐷 阅读(107) 评论(0) 推荐(0)

interval intersection

摘要： example： input is two non-overlapping list of intervals , output is the list of overlaps l1 : [0, 2], [5, 7]. [9, 11] l2: [1, 3], [6, 10] overlap is [ 阅读全文

posted @ 2018-08-11 03:23 猪猪🐷 阅读(240) 评论(0) 推荐(0)

preorder iterator of binary tree

摘要：实现 next（）， hasNext() . Follow up：实现 remove, remove 要求删除next（）last visited node and its subtree. 阅读全文

posted @ 2018-08-11 03:19 猪猪🐷 阅读(123) 评论(0) 推荐(0)

k sorted list iterator.

摘要： k sorted list iterator. 写个被多次 call 的 getNext()。没要求用 iterator, 于是 heap 秒了。面试官表示很满意。阅读全文

posted @ 2018-08-11 03:18 猪猪🐷 阅读(76) 评论(0) 推荐(0)

merge sorted iterator

摘要： merge sorted iterator 这个小班讲过，小班文档上应该有阅读全文

posted @ 2018-08-11 03:17 猪猪🐷 阅读(81) 评论(0) 推荐(0)

281 Zigzag Iterator

摘要： Given two 1d vectors, implement an iterator to return their elements alternately. Example: Follow up: What if you are given k 1d vectors? How well can 阅读全文

posted @ 2018-08-10 16:31 猪猪🐷 阅读(81) 评论(0) 推荐(0)

647. Palindromic Substrings

摘要： Given a string, your task is to count how many palindromic substrings in this string. The substrings with different start indexes or end indexes are c 阅读全文

posted @ 2018-08-10 15:32 猪猪🐷 阅读(92) 评论(0) 推荐(0)

140. Word Break II

摘要： 140. Word Break II dfs + memo Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, add spaces in s to construct 阅读全文

posted @ 2018-08-10 15:26 猪猪🐷 阅读(142) 评论(0) 推荐(0)

170 Two Sum III - Data structure design

摘要： Design and implement a TwoSum class. It should support the following operations: add and find. add - Add the number to an internal data structure.find 阅读全文

posted @ 2018-08-10 15:25 猪猪🐷 阅读(118) 评论(0) 推荐(0)

347. Top K Frequent Elements

摘要： Given a non-empty array of integers, return the k most frequent elements. Example 1: Input: nums = [1,1,1,2,2,3], k = 2 Output: [1,2] Example 2: Input 阅读全文

posted @ 2018-08-10 15:19 猪猪🐷 阅读(128) 评论(0) 推荐(0)

146 LRU Cache

摘要：这个题的 node class, constructor, global vars , 怎么写该注意几点该注意的： use helper functions, add, and deleteNode, add : add node to the front, deleteNode: delete 阅读全文

posted @ 2018-08-10 15:18 猪猪🐷 阅读(173) 评论(0) 推荐(0)

摘要： 126. Word Ladder II Given two words (beginWord and endWord), and a dictionary's word list, find all shortest transformation sequence(s) from beginWord to endWord, such that: 1. Only one letter can... 阅读全文

posted @ 2018-08-10 15:12 猪猪🐷 阅读(272) 评论(0) 推荐(0)

395 Longest Substring with At Least K Repeating Characters

摘要： Find the length of the longest substring T of a given string (consists of lowercase letters only) such that every character in T appears no less than 阅读全文

posted @ 2018-08-10 15:07 猪猪🐷 阅读(369) 评论(0) 推荐(0)

247. Strobogrammatic Number II

摘要： 1 1 1 1 1 6 6 8 9 9 8 9 0 6 6 9 8 8 8 0 0 So we Cann’t have 0 at the very out side of the number Since any number with leading 0 is not valid And then 阅读全文

posted @ 2018-08-10 15:04 猪猪🐷 阅读(689) 评论(0) 推荐(0)

282 Expression Add Operators

摘要： Given a string that contains only digits 0-9 and a target value, return all possibilities to add binary operators (not unary) +, -, or * between the d 阅读全文

posted @ 2018-08-10 15:03 猪猪🐷 阅读(131) 评论(0) 推荐(0)

227. Basic Calculator II

摘要： we have a string, can look like 32 + 2 * 46 And we are not sure if there is any white space anywhere in the string So we use s = s.replaceAll(" ", "") 阅读全文

posted @ 2018-08-10 15:00 猪猪🐷 阅读(134) 评论(0) 推荐(0)

10. Regular Expression Matching

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 阅读全文

posted @ 2018-08-10 14:52 猪猪🐷 阅读(75) 评论(0) 推荐(0)

44 Wildcard Matching

摘要： Given an input string (s) and a pattern (p), implement wildcard pattern matching with support for '?' and '*'. The matching should cover the entire in 阅读全文

posted @ 2018-08-10 14:51 猪猪🐷 阅读(88) 评论(0) 推荐(0)

112. Path Sum

摘要： 112. Path Sum https://www.youtube.com/watch?v=zdClzfnkvDY Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that addin 阅读全文

posted @ 2018-08-10 14:50 猪猪🐷 阅读(101) 评论(0) 推荐(0)

124. Binary Tree Maximum Path Sum

摘要： 124. Binary Tree Maximum Path Sum https://github.com/tongzhang1994/Facebook-Interview-Coding/blob/master/Longest%20Path%20in%20Binary%20Tree.java http 阅读全文

posted @ 2018-08-10 14:49 猪猪🐷 阅读(86) 评论(0) 推荐(0)

437 Path Sum III （Find the number of paths that sum to a given value.）

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 阅读全文

posted @ 2018-08-10 14:48 猪猪🐷 阅读(123) 评论(0) 推荐(0)

113. Path Sum II (find all root-to-leaf paths where each path's sum equals the given sum.)

摘要： Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. Note: A leaf is a node with no children. Exampl 阅读全文

posted @ 2018-08-10 14:48 猪猪🐷 阅读(125) 评论(0) 推荐(0)

34 Find First and Last Position of Element in Sorted Array

摘要：这个也是，得自己走例子，才知道什么时候需要post processing , 什么时候不需要，这个题一个问不需要，第二问就需要了所以不要背答案，要真的理解，自己走例子 Your algorithm's runtime complexity must be in the order of 阅读全文

posted @ 2018-08-10 14:47 猪猪🐷 阅读(556) 评论(0) 推荐(0)

491 Increasing Subsequences

摘要： Given an integer array, your task is to find all the different possible increasing subsequences of the given array, and the length of an increasing su 阅读全文

posted @ 2018-08-10 14:46 猪猪🐷 阅读(132) 评论(0) 推荐(0)

65. Valid Number

摘要： Validate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => true Note: It is intended for the 阅读全文

posted @ 2018-08-10 14:46 猪猪🐷 阅读(140) 评论(0) 推荐(0)

381. Insert Delete GetRandom O(1) - Duplicates allowed

摘要： 381. Insert Delete GetRandom O(1) - Duplicates allowed Design a data structure that supports all following operations in average O(1) time. Note: Duplicate elements are allowed. 1. insert(val): Ins... 阅读全文

posted @ 2018-08-10 14:44 猪猪🐷 阅读(143) 评论(0) 推荐(0)

57 Insert Interval

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 阅读全文

posted @ 2018-08-10 14:43 猪猪🐷 阅读(108) 评论(0) 推荐(0)

56. Merge Intervals

摘要： merge intervals leetcode 88 merge interval的变体, 问了下时间复杂度，求interval所覆盖区间的总长度。Follow up: nlogn的排序算法有哪些。哪些排序算法是稳定的。解释为什么quick sort不稳定。我没想到没问这么基础的问题，答得一般般啦阅读全文

posted @ 2018-08-10 14:42 猪猪🐷 阅读(147) 评论(0) 推荐(0)

380 Insert Delete GetRandom O(1)

摘要： 380 Insert Delete GetRandom O(1) Design a data structure that supports all following operations in average O(1) time. 1. insert(val): Inserts an item val to the set if not already present. 2. remo... 阅读全文

posted @ 2018-08-10 14:41 猪猪🐷 阅读(111) 评论(0) 推荐(0)

246 Strobogrammatic Number I

摘要： A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to determine if a number i 阅读全文

posted @ 2018-08-10 14:40 猪猪🐷 阅读(90) 评论(0) 推荐(0)

127 Word Ladder

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, 阅读全文

posted @ 2018-08-10 14:39 猪猪🐷 阅读(143) 评论(0) 推荐(0)

346. Moving Average from Data Stream

摘要： the next() func takes in an integer, First check if the queue size() == maxSize if it’s the same, then we poll the top, which is the one we added firs 阅读全文

posted @ 2018-08-10 14:38 猪猪🐷 阅读(145) 评论(0) 推荐(0)

53 Maximum Subarray

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 阅读全文

posted @ 2018-08-10 14:36 猪猪🐷 阅读(82) 评论(0) 推荐(0)

129 Sum Root to Leaf Numbers (An example is the root-to-leaf path 1->2->3 which represents the number 123.)

摘要： Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path 1->2->3 whic 阅读全文

posted @ 2018-08-10 14:35 猪猪🐷 阅读(83) 评论(0) 推荐(0)

692 Top K Frequent Words

摘要：这个写的少， pq 里存的是 map.entry<string, integer> 自己这些 comparator overide 要专门写，然后 maxheap(a,b). a < b, return 1 minheap(a, b) a < b, return -1 map.entryset 阅读全文

posted @ 2018-08-10 14:34 猪猪🐷 阅读(169) 评论(0) 推荐(0)

417. Pacific Atlantic Water Flow

摘要： Given an m x n matrix of non-negative integers representing the height of each unit cell in a continent, the "Pacific ocean" touches the left and top 阅读全文

posted @ 2018-08-09 19:07 猪猪🐷 阅读(117) 评论(0) 推荐(0)

733. Flood Fill

摘要： An image is represented by a 2-D array of integers, each integer representing the pixel value of the image (from 0 to 65535). Given a coordinate (sr, 阅读全文

posted @ 2018-08-09 19:06 猪猪🐷 阅读(105) 评论(0) 推荐(0)

317. Shortest Distance from All Buildings

摘要： You want to build a house on an empty land which reaches all buildings in the shortest amount of distance. You can only move up, down, left and right. 阅读全文

posted @ 2018-08-09 19:04 猪猪🐷 阅读(194) 评论(0) 推荐(0)

567. Permutation in String

摘要： Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutati 阅读全文

posted @ 2018-08-09 19:02 猪猪🐷 阅读(83) 评论(0) 推荐(0)

269. alien dictionary

摘要： Using “break” in for loop public class Test { public static void main(String args[]) { int [] numbers = {10, 20, 30, 40, 50}; for(int x : numbers ) { 阅读全文

posted @ 2018-08-09 19:00 猪猪🐷 阅读(183) 评论(0) 推荐(0)

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