这里我们要推荐的是一个在线工具，也是支持Python代码的执行，一个在线的Python代码编辑器

分享一个好用的 Python 在线编辑器

What we want to recommend here is an online tool that also supports the execution of Python code, an online Python code editor

Share a Useful Python Online Editor

小编的插件已经发布到谷歌商店了，插件实现了无需登录一键复制 CSDN 代码。

谷歌插件：无需登录一键复制 CSDN 代码

My extension has been released to the Google Web Store. The extension realizes one-click copying of CSDN code without logging in.

Google Extension: One-Click Copy CSDN Code without Logging In

之前小编研究过验证码识别这一块的内容，发现了一个验证码识别服务提供商 2Captcha，并且尝试了下他们的服务，效果很不错。

验证码服务 2Captcha 测评 2022 | 原理 用途 入门

I have studied captcha identification before, and found a captcha identification service provider 2Captcha, and tried their service, the effect is very good.

2Captcha Review 2022 | Principles & Usage & Getting Started

正则表达式提取 git 提交记录中的新增代码行

正则匹配多行文本

Regular expression to extract new lines of code in git commits.

Regular Expression to Match Multiple Lines of Text

我们在登陆网站的时候经常会出现验证码，验证码的目的就是为了防止机器登陆、自动化脚本操作，那么有没有办法让脚本能自动识别验证码实现登陆呢？

Nodejs Playwright 2Captcha 验证码识别实现自动登陆

When we log in to the website, we often see verification codes. The purpose of verification codes is to prevent machine logins and automate script operations. Is there a way for scripts to automatically identify verification codes to achieve login?

How to Bypass Captcha Automatic Login with Nodejs Playwright 2Captcha

我们在使用 Python 开发的时候，通常会用到一些好用的第三方库，推荐用 pip 来安装。一般情况下都没有什么问题，但是有些小伙伴会碰到 pip 安装第三方库报错、pip install 卡住不动等安装失败的情况。

pip 安装第三方库报错最全解决方案

When we use Python to develop, we usually use some useful third-party libraries. It is recommended to use pip to install. Under normal circumstances, there is no problem, but some small partners will encounter installation failures such as pip installation of third-party libraries and errors, pip install stuck and other installation failures.

pip Install Third-Party Library Error

LeetCode刷题笔记，给你一个长度为 n 的整数数组 nums ，其中 nums 的所有整数都在范围 [1, n] 内，且每个整数出现 一次 或 两次 。请你找出所有出现 两次 的整数，并以数组形式返回。

LeetCode笔记：数组中重复的数据

LeetCode problem solving notes. Given an integer array nums of length n where all the integers of nums are in the range [1, n] and each integer appears once or twice, return an array of all the integers that appears twice.

LeetCode Notes: Find All Duplicates in an Array

Event Bus 事件总线，通常作为多个模块间的通信机制，相当于一个事件总线，一个模块发送消息，其它模块接受消息，就达到了通信的作用。

如何在 JavaScript 中实现 Event Bus

The Event Bus is usually used as a communication mechanism between multiple modules, which is equivalent to an event bus. One module sends messages, and other modules receive messages, which achieves the function of communication.

How to Implement an Event Bus in JavaScript

给定总玩家数 n，以及按 [玩家编号,对应可传递玩家编号] 关系组成的二维数组 relation。返回信息从小 A (编号 0 ) 经过 k 轮传递到编号为 n-1 的小伙伴处的方案数。

LeetCode笔记：传递信息

Given the total number of players n, and a two-dimensional array relation formed by the relation [player number, corresponding to passable player number]. Returns the number of solutions in which information is passed from small A (number 0 ) to the small partner numbered n-1 through k rounds.

LeetCode Notes: Send message

学习简单场景下的时间复杂度和空间复杂度的计算方法

如何计算时间复杂度和空间复杂度

Learn how to calculate time complexity and space complexity in simple scenarios

Time Complexity and Space Complexity

最近遇到了阿里云 ECS 服务器被 DDoS 攻击的问题，说明我们的服务器安全性有待提高。从 ssh 登陆方面考虑，可以给 linux 系统设置子用户，禁止 root 登陆，能够提升一定的安全性。

CentOS 创建新用户赋予 root 权限并禁止 root 登陆

Recently, we encountered the problem that Alibaba Cloud ECS server was attacked by DDoS, indicating that our server security needs to be improved. From the perspective of ssh login, you can set sub-users for the linux system and prohibit root login, which can improve certain security.

Create a New User Grant Root Privileges and Disabl SSH Root Login on CentOS

在安装 VMware 后，启动 macOS 虚拟机的时候，碰到了`vcpu-0`和 `vcpu-1` 报错。

Vmware Workstation16 出现 "VMware Workstation 不可恢复错误：(vcpu-1)"故障解决

After installing VMware, when starting the macOS virtual machine, I encountered `vcpu-0` and `vcpu-1` errors.

"VMware Workstation Unrecoverable Error: (vcpu-1)" Troubleshooting for Vmware Workstation16

LeetCode刷题笔记，给你整数 n，请返回第 n 个泰波那契数 Tn 的值。

LeetCode笔记：第 N 个泰波那契数

LeetCode problem solving notes. Given n, return the value of Tn.

LeetCode Notes: N-th Tribonacci Number

python turtle和tkinter结合实现绘制并下载冰墩墩图片

实现人手一个冰墩墩python画冰墩墩源码

The combination of python turtle and tkinter realizes drawing and downloading Bing Dwen Dwen pictures

Python Draw Bing Dwen Dwen Source Code

LeetCode刷题笔记，给定两个字符串 s 和 t，它们只包含小写字母。字符串 t 由字符串 s 随机重排，然后在随机位置添加一个字母。请找出在 t 中被添加的字母。

LeetCode笔记：找不同

LeetCode problem solving notes. You are given two strings s and t.String t is generated by random shuffling string s and then add one more letter at a random position.Return the letter that was added to t.

LeetCode Notes: Find the Difference

LeetCode刷题笔记，给你两个字符串：ransomNote 和 magazine ，判断 ransomNote 能不能由 magazine 里面的字符构成。

LeetCode笔记：赎金信

LeetCode problem solving notes. Given two stings ransomNote and magazine, return true if ransomNote can be constructed from magazine and false otherwise.

LeetCode Notes: Ransom Note

python selenium解析网页，requests请求视频地址，分片下载视频存储本地，实时输出视频下载进度

Python一键下载视频脚本分享

Python selenium parses the web page, requests the video address, downloads the video in fragments and stores it locally, and outputs the video download progress in real time

Python One-Click Download Video

LeetCode刷题笔记，给定一种规律 pattern 和一个字符串 str ，判断 str 是否遵循相同的规律。

LeetCode笔记：单词规律

LeetCode problem solving notes. Given a pattern and a string s, find if s follows the same pattern.

LeetCode Notes: Word Pattern

假设你有 n 个版本 [1, 2, ..., n]，你想找出导致之后所有版本出错的第一个错误的版本。

LeetCode笔记：第一个错误的版本

LeetCode problem solving notes. Suppose you have n versions [1, 2, ..., n] and you want to find out the first bad one, which causes all the following ones to be bad.

LeetCode Notes: First Bad Version

免费开源的高性能javascript电子表格 x-sheet，在线excel编辑器，丰富的单元格样式，富文本，边框倾斜，合并单元格，冻结，撤销重做，格式刷等核心功能，还支持导入导出xlsx文件，多实例，支持大数据量。

免费开源的高性能JavaScript电子表格：X-Sheet入门体验

Free and open source high-performance javascript spreadsheet x-sheet, online excel editor, rich cell styles, rich text, border tilt, merge cells, freeze, undo redo, format brush and other core functions, and also support import and export xlsx files, multiple instances, and support for large amounts of data.

Free and Open Source High-Performance JavaScript Spreadsheet: X-Sheet Tutorial

LeetCode刷题笔记，给定一个包含 [0, n] 中 n 个数的数组 nums ，找出 [0, n] 这个范围内没有出现在数组中的那个数。

LeetCode笔记：丢失的数字

LeetCode problem solving notes. Given an array nums containing n distinct numbers in the range [0, n], return the only number in the range that is missing from the array.

LeetCode Notes: Missing Number

LeetCode刷题笔记，给定一个非负整数 num，反复将各个位上的数字相加，直到结果为一位数。

LeetCode笔记：各位相加

LeetCode problem solving notes. Given an integer num, repeatedly add all its digits until the result has only one digit, and return it.

LeetCode Notes: Add Digits

我们通常会在react项目中使用jsx，如何在不使用react的情况下，解析jsx？

自定义jsx解析工厂函数

We usually use jsx in react projects. How to parse jsx without using react?

Custom JSX Factory Function

LeetCode刷题笔记，给你一个二叉树的根节点 root ，按 任意顺序 ，返回所有从根节点到叶子节点的路径。

LeetCode笔记：二叉树的所有路径

LeetCode problem solving notes. Given the root of a binary tree, return all root-to-leaf paths in any order.

LeetCode Notes: Binary Tree Paths

在js模块化开发中，经常会碰到循环依赖的问题，报错Super expression must either be null or a function

解决js循环依赖

In js modular development, we often encounter the problem of circular dependencies and report errors: Super expression must either be null or a function.

Fix Circular Module Dependencies in JavaScript & TypeScript

从基础API入手，演示如何使用canvas绘制任何你想要的效果

Canvas基础API使用教程

Start with the basic API, demonstrate how to use canvas to draw any effect you want.

Canvas Basic API Usage Tutorial

仅仅使用正则表达式替换字符串的方式，实现自动补全时间日期数字前缀加0的格式化操作

js正则格式化日期时间自动补0

Only use regular expressions to replace strings to achieve the formatting operation of automatically completing the time and date number prefix plus 0.

JS Regular Format Date and Time Automatically Fill 0

关于range input范围滑块控件，每个浏览器实现效果不同。这里演示直接修改css样式达到统一样式的效果。

自定义范围滑块

Regarding the range input range slider control, each browser achieves different effects. This demonstrates the effect of directly modifying the css style to achieve a unified style.

Customized Range Slider

LeetCode刷题笔记，请你仅使用两个栈实现先入先出队列。队列应当支持一般队列支持的所有操作（push、pop、peek、empty）。

LeetCode笔记：用栈实现队列

LeetCode problem solving notes. Implement a first in first out (FIFO) queue using only two stacks. The implemented queue should support all the functions of a normal queue (push, peek, pop, and empty).

LeetCode Notes: Implement Queue using Stacks

LeetCode刷题笔记，请你仅使用两个队列实现一个后入先出（LIFO）的栈，并支持普通栈的全部四种操作（push、top、pop 和 empty）。

LeetCode笔记：用队列实现栈

LeetCode problem solving notes. Implement a last-in-first-out (LIFO) stack using only two queues. The implemented stack should support all the functions of a normal stack (push, top, pop, and empty).

LeetCode Notes: Implement Stack using Queues

简易脚本实现Python + Selenium 自动化运行《人生重开模拟器》游戏

Python + Selenium 自动化测试《人生重开模拟器》

Simple script to realize Python + Selenium to automatically run the Life Restart Simulator game

Python + Selenium Automated Test Life Restart Simulator

LeetCode刷题笔记，给你一个整数 n，请你判断该整数是否是 2 的幂次方。如果是，返回 true ；否则，返回 false 。

LeetCode笔记：2 的幂

LeetCode problem solving notes. Given an integer n, return true if it is a power of two. Otherwise, return false.

LeetCode Notes: Power of Two

LeetCode刷题笔记，给定一个无重复元素的有序整数数组 nums 。返回 恰好覆盖数组中所有数字 的 最小有序 区间范围列表。也就是说，nums 的每个元素都恰好被某个区间范围所覆盖，并且不存在属于某个范围但不属于 nums 的数字 x 。

LeetCode笔记：汇总区间

LeetCode problem solving notes. You are given a sorted unique integer array nums.Return the smallest sorted list of ranges that cover all the numbers in the array exactly. That is, each element of nums is covered by exactly one of the ranges, and there is no integer x such that x is in one of the ranges but not in nums.

LeetCode Notes: Summary Ranges

LeetCode刷题笔记，给定一个整数数组和一个整数 k，判断数组中是否存在两个不同的索引 i 和 j，使得 nums [i] = nums [j]，并且 i 和 j 的差的 绝对值 至多为 k。

LeetCode笔记：存在重复元素 II

LeetCode problem solving notes. Given an integer array nums and an integer k, return true if there are two distinct indices i and j in the array such that nums[i] == nums[j] and abs(i - j) <= k.

LeetCode Notes: Contains Duplicate II

LeetCode刷题笔记，给定两个字符串 s 和 t，判断它们是否是同构的。

LeetCode笔记：同构字符串

LeetCode problem solving notes. Given two strings s and t, determine if they are isomorphic.

LeetCode Notes: Isomorphic Strings

LeetCode刷题笔记，给定一个非负整数 num。对于 0 ≤ i ≤ num 范围中的每个数字 i ，计算其二进制数中的 1 的数目并将它们作为数组返回。

LeetCode笔记：位1的个数

LeetCode problem solving notes. Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight).

LeetCode Notes: Number of 1 Bits

LeetCode刷题笔记，颠倒给定的 32 位无符号整数的二进制位。

LeetCode笔记：颠倒二进制位

LeetCode problem solving notes. Reverse bits of a given 32 bits unsigned integer.

LeetCode Notes: Reverse Bits

LeetCode刷题笔记，给你一个整数数组  flowerbed 表示花坛，由若干 0 和 1 组成，其中 0 表示没种植花，1 表示种植了花。另有一个数 n ，能否在不打破种植规则的情况下种入 n 朵花？能则返回 true ，不能则返回 false。

LeetCode笔记：种花问题

LeetCode problem solving notes. You have a long flowerbed in which some of the plots are planted, and some are not. However, flowers cannot be planted in adjacent plots.

LeetCode Notes: Can Place Flowers

LeetCode刷题笔记，两个整数之间的 汉明距离 指的是这两个数字对应二进制位不同的位置的数目。给你两个整数 x 和 y，计算并返回它们之间的汉明距离。

LeetCode笔记：汉明距离

LeetCode problem solving notes. The Hamming distance between two integers is the number of positions at which the corresponding bits are different.Given two integers x and y, return the Hamming distance between them.

LeetCode Notes: Hamming Distance

最近做业务开发的时候，遇到一个需求，用户打开弹窗填写内容时，想参照下弹窗空白背景处的内容，但是弹窗挡住了视线，于是用户就想是否可以将弹窗任意拖动

原生js实现全屏弹窗拖拽

When I was doing business development recently, I encountered a requirement. When the user opened the pop-up window to fill in the content, he wanted to refer to the content in the blank background of the pop-up window, but the pop-up window blocked his sight, so the user wondered whether he could drag the pop-up window arbitrarily.

Full-Screen Pop-Up Window Drag and Drop by Vanilla JavaScript

LeetCode笔记：比特位计数

LeetCode problem solving notes. Given a non-empty array of integers nums, every element appears twice except for one. Find that single one.

LeetCode Notes: Counting Bits

LeetCode刷题笔记，编写一个算法来判断一个数 n 是不是快乐数。

LeetCode笔记：快乐数

LeetCode problem solving notes. Write an algorithm to determine if a number n is happy.

LeetCode Notes: Happy Number

LeetCode刷题笔记，给定一个二叉树，返回它的 后序 遍历。

LeetCode笔记：二叉树的后序遍历

LeetCode problem solving notes. Given the root of a binary tree, return the postorder traversal of its nodes' values.

LeetCode Notes: Binary Tree Postorder Traversal

现有一个树形结构的菜单，支持无限的嵌套层级，需要根据用户点击的某个子菜单，获取到这个子菜单所在节点的路径，类似于面包屑效果。

实时获取树形菜单节点路径

There is a tree structure menu that supports unlimited nesting levels. It is necessary to obtain the path of the node where the submenu is located according to a certain submenu that the user clicks, which is similar to the breadcrumb effect.

Get the Tree Menu Node Path

LeetCode刷题笔记，一个长度为n-1的递增排序数组中的所有数字都是唯一的，并且每个数字都在范围0～n-1之内。在范围0～n-1内的n个数字中有且只有一个数字不在该数组中，请找出这个数字。

LeetCode笔记：0～n-1中缺失的数字

LeetCode problem solving notes. All numbers in an increasing sorted array of length n-1 are unique, and each number is in the range of 0 to n-1. There is only one number among n numbers in the range 0～n-1 that is not in the array. Please find this number.

LeetCode Notes: Numbers Missing From 0 to N-1

LeetCode刷题笔记，给定单向链表的头指针和一个要删除的节点的值，定义一个函数删除该节点。

LeetCode笔记：删除链表的节点

LeetCode problem solving notes. Given the head pointer of the singly linked list and the value of a node to be deleted, define a function to delete the node.

LeetCode Notes: Delete the Node of the Linked List

LeetCode刷题笔记，给定一个Excel表格中的列名称，返回其相应的列序号。

LeetCode笔记：Excel表列序号

LeetCode problem solving notes. Given a string columnTitle that represents the column title as appear in an Excel sheet, return its corresponding column number.

LeetCode Notes: Excel Sheet Column Number

LeetCode刷题笔记，给定一个包含大写字母和小写字母的字符串，找到通过这些字母构造成的最长的回文串。

LeetCode笔记：最长回文串

LeetCode problem solving notes. Given a string s which consists of lowercase or uppercase letters, return the length of the longest palindrome that can be built with those letters.

LeetCode Notes: Longest Palindrome

LeetCode刷题笔记，给你一个 m 行 n 列的矩阵 matrix ，请按照 顺时针螺旋顺序 ，返回矩阵中的所有元素。

LeetCode笔记：螺旋矩阵

LeetCode problem solving notes. Given an m x n matrix, return all elements of the matrix in spiral order.

LeetCode Notes: Spiral Matrix

LeetCode刷题笔记，编写一个 SQL 查询，满足条件：无论 person 是否有地址信息，都需要基于上述两表提供 person 的以下信息

LeetCode笔记：组合两个表

LeetCode problem solving notes. Write a SQL query for a report that provides the following information for each person in the Person table, regardless if there is an address for each of those people.

Articles

分享一个好用的 Python 在线编辑器

谷歌插件：无需登录一键复制 CSDN 代码

验证码服务 2Captcha 测评 2022 | 原理用途入门

正则匹配多行文本

Nodejs Playwright 2Captcha 验证码识别实现自动登陆

pip 安装第三方库报错最全解决方案

LeetCode笔记：数组中重复的数据

如何在 JavaScript 中实现 Event Bus

LeetCode笔记：传递信息

如何计算时间复杂度和空间复杂度

Articles

分享一个好用的 Python 在线编辑器

谷歌插件：无需登录一键复制 CSDN 代码

验证码服务 2Captcha 测评 2022 | 原理 用途 入门

正则匹配多行文本

Nodejs Playwright 2Captcha 验证码识别实现自动登陆

pip 安装第三方库报错最全解决方案

LeetCode笔记：数组中重复的数据

如何在 JavaScript 中实现 Event Bus

LeetCode笔记：传递信息

如何计算时间复杂度和空间复杂度

验证码服务 2Captcha 测评 2022 | 原理用途入门