01 2023 档案
摘要：N-ary Tree Preorder Traversal Given the root of an n-ary tree, return the preorder traversal of its nodes' values. Nary-Tree input serialization is re
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摘要：N-ary Tree postorder Traversal Given the root of an n-ary tree, return the postorder traversal of its nodes' values. Nary-Tree input serialization is
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摘要：Construct String from Binary Tree Given the root of a binary tree, construct a string consisting of parenthesis and integers from a binary tree with t
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摘要：Merge Two Binary Trees You are given two binary trees root1 and root2. Imagine that when you put one of them to cover the other, some nodes of the two
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摘要：Average of Levels in Binary Tree Given the root of a binary tree, return the average value of the nodes on each level in the form of an array. Answers
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摘要：Implement Queue using Stacks Implement a first in first out (FIFO) queue using only two stacks. The implemented queue should support all the functions
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摘要：Two Sum IV - Input is a BST Given the root of a binary search tree and an integer k, return true if there exist two elements in the BST such that thei
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摘要：Image Smoother An image smoother is a filter of the size 3 x 3 that can be applied to each cell of an image by rounding down the average of the cell a
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摘要：Second Minimum Node In a Binary Tree Given a non-empty special binary tree consisting of nodes with the non-negative value, where each node in this tr
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摘要：Search in a Binary Search Tree You are given the root of a binary search tree (BST) and an integer val. Find the node in the BST that the node's value
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摘要：网络上查到的使用 netsh 命令，没有用 使用下面的命令开启热点 @echo off powershell.exe -encodedCommand WwBXAGkAbgBkAG8AdwBzAC4AUwB5AHMAdABlAG0ALgBVAHMAZQByAFAAcgBvAGYAaQBsAGUALgB
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摘要：find . -name \*.log -print0 | xargs -0 grep -n -H "Something" 参考 Filenames and linenumbers for the matches of cat and grep
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摘要：Guess Number Higher or Lower 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 pick
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摘要：Convert a Number to Hexadecimal Given an integer num, return a string representing its hexadecimal representation. For negative integers, two’s comple
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摘要：Find Mode in Binary Search Tree Given the root of a binary search tree (BST) with duplicates, return all the mode(s) (i.e., the most frequently occurr
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摘要：Minimum Absolute Difference in BST Given the root of a Binary Search Tree (BST), return the minimum absolute difference between the values of any two
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摘要：Diameter of Binary Tree Given the root of a binary tree, return the length of the diameter of the tree. The diameter of a binary tree is the length of
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摘要：Maximum Depth of N-ary Tree Given a n-ary tree, find its maximum depth. The maximum depth is the number of nodes along the longest path from the root
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摘要：Subtree of Another Tree Given the roots of two binary trees root and subRoot, return true if there is a subtree of root with the same structure and no
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摘要：Range Sum Query - Immutable Given an integer array nums, handle multiple queries of the following type: Calculate the sum of the elements of nums betw
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摘要：Power of Three Given an integer n, return true if it is a power of three. Otherwise, return false. An integer n is a power of three, if there exists a
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摘要：Power of Four Given an integer n, return true if it is a power of four. Otherwise, return false. An integer n is a power of four, if there exists an i
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摘要：Middle of the Linked List Given the head of a singly linked list, return the middle node of the linked list. If there are two middle nodes, return the
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摘要：Uncommon Words from Two Sentences A sentence is a string of single-space separated words where each word consists only of lowercase letters. A word is
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摘要：DI String Match A permutation perm of n + 1 integers of all the integers in the range [0, n] can be represented as a string s of length n where: s[i]
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摘要：Find Common Characters Given a string array words, return an array of all characters that show up in all strings within the words (including duplicate
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摘要：Set Mismatch You have a set of integers s, which originally contains all the numbers from 1 to n. Unfortunately, due to some error, one of the numbers
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摘要：Valid Mountain Array Given an array of integers arr, return true if and only if it is a valid mountain array. Recall that arr is a mountain array if a
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摘要：Degree of an Array Given a non-empty array of non-negative integers nums, the degree of this array is defined as the maximum frequency of any one of i
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摘要：Distribute Candies Alice has n candies, where the ith candy is of type candyType[i]. Alice noticed that she started to gain weight, so she visited a d
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摘要：Longest Harmonious Subsequence We define a harmonious array as an array where the difference between its maximum value and its minimum value is exactl
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摘要：Range Addition II You are given an m x n matrix M initialized with all 0's and an array of operations ops, where ops[i] = [ai, bi] means M[x][y] shoul
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摘要：Can Place Flowers You have a long flowerbed in which some of the plots are planted, and some are not. However, flowers cannot be planted in adjacent p
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摘要：LongestContinuous Increasing Subsequence Given an unsorted array of integers nums, return the length of the longest continuous increasing subsequence
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摘要：Baseball Game You are keeping the scores for a baseball game with strange rules. At the beginning of the game, you start with an empty record. You are
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摘要：Excel Sheet Column Number Given a string columnTitle that represents the column title as appears in an Excel sheet, return its corresponding column nu
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摘要：Implement Stack using Queues Implement a last-in-first-out (LIFO) stack using only two queues. The implemented stack should support all the functions
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摘要：Palindrome Linked List Given the head of a singly linked list, return true if it is a palindrome or false otherwise. Example 1: Input: head = [1,2,2,1
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摘要：Max Consecutive Ones Given a binary array nums, return the maximum number of consecutive 1's in the array. Example 1: Input: nums = [1,1,0,1,1,1] Outp
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摘要：Number of Segments in a String Given a string s, return the number of segments in the string. A segment is defined to be a contiguous sequence of non-
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摘要：Next Greater Element I The next greater element of some element x in an array is the first greater element that is to the right of x in the same array
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摘要：Longest Uncommon Subsequence I Given two strings a and b, return the length of the longest uncommon subsequence between a and b. If the longest uncomm
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摘要：Student Attendance Record I You are given a string s representing an attendance record for a student where each character signifies whether the studen
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摘要：Longest Palindrome Given a string s which consists of lowercase or uppercase letters, return the length of the longest palindrome that can be built wi
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摘要：Reverse Vowels of a String Given a string s, reverse only all the vowels in the string and return it. The vowels are 'a', 'e', 'i', 'o', and 'u', and
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摘要：Maximum Average Subarray I You are given an integer array nums consisting of n elements, and an integer k. Find a contiguous subarray whose length is
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摘要：Binary Tree Tilt Given the root of a binary tree, return the sum of every tree node's tilt. The tilt of a tree node is the absolute difference between
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摘要：Intersection of Two Arrays Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must be unique
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摘要：Intersection of Two Arrays II Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must appear
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摘要：Valid Perfect Square Given a positive integer num, return true if num is a perfect square or false otherwise. A perfect square is an integer that is t
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摘要：First Unique Character in a String Given a string s, find the first non-repeating character in it and return its index. If it does not exist, return -
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摘要：Third Maximum Number Given an integer array nums, return the third distinct maximum number in this array. If the third maximum does not exist, return
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摘要：Reverse Linked List Given the head of a singly linked list, reverse the list, and return the reversed list. Example 1: Input: head = [1,2,3,4,5] Outpu
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摘要：Excel Sheet Column Title Given an integer columnNumber, return its corresponding column title as it appears in an Excel sheet. For example: A -> 1 B -
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摘要：Binary Tree Postorder Traversal Given the root of a binary tree, return the postorder traversal of its nodes' values. Example 1: Input: root = [1,null
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摘要：Binary Tree Preorder Traversal Given the root of a binary tree, return the preorder traversal of its nodes' values. Example 1: Input: root = [1,null,2
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摘要：Best Time to Buy and Sell Stock You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your
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摘要：Arranging Coins You have n coins and you want to build a staircase with these coins. The staircase consists of k rows where the ith row has exactly i
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摘要：Repeated Substring Pattern Given a string s, check if it can be constructed by taking a substring of it and appending multiple copies of the substring
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摘要：Construct the Rectangle A web developer needs to know how to design a web page's size. So, given a specific rectangular web page’s area, your job by n
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摘要：Reverse Words in a String III Given a string s, reverse the order of characters in each word within a sentence while still preserving whitespace and i
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摘要：Island Perimeter You are given row x col grid representing a map where grid[i][j] = 1 represents land and grid[i][j] = 0 represents water. Grid cells
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摘要：win10 系统下的 Tim 个人文件夹默认保存在“我的文档”，虽然有个自定义选项，但是重启后会自动还原到“我的文档”。 可以用 windows 提供的文件夹映射来解决这个问题 MKLINK [[/D] | [/H] | [/J]] Link Target 例如，我们想把 Tim 文件夹放到 D 盘
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