• ## Binary tree recursion routine (4): lowest common ancestor, maximum happiness of Party

Time：2022-3-6

Today, continue the recursive routine of binary tree. 1、 Lowest common ancestor Given the head node of a binary tree and the other two nodes a and B, return the lowest common ancestor of a and B. Definition of lowest common ancestor: A and B look up and find the first same ancestor (this common […]

• ## Ali P8 talk: the harvest is more than sol optimization. Seize the essence of SQL and take you to appreciate the world of SQL!

Time：2021-12-26

Let me start by saying: Some people have Jianghu, Jianghu has it system, it system has database, database has SQL, SQL application can be summarized in one word: “wide”. In addition, its simplicity and easy to learn, SQL implementation can also be summarized in one word: “happy”. However, although the implementation of SQL is simple, […]

• ## Learning Flink from 0 to 1 – Introduction to data sink

Time：2021-11-27

preface In the last articleLearning Flink from 0 to 1 – Introduction to data sourceAfter explaining the Flink data source, let’s talk about Flink data sink here. First, sink means: You can probably guess! Data sink means storing data. As shown in the figure above, source is the source of data. In the middle, compute […]

• ## Liang Xu is so convinced by the arrangement of a million big V’s that he takes a picture with a beautiful lady

Time：2021-5-12

Hello, I’m Liang Xu. A lot of people ask me, Liang Xu,What time did you spend so much time and energy on writing the official account from the media? In fact, the reason is very simple. I want to be a sideline. If I really lose my job at the age of 35, I will […]

• ## The routine and common complexity of complexity analysis

Time：2021-3-30

preface This article is included in the album:http://dwz.win/HjK, click to unlock more knowledge of data structure and algorithm. Hello, I’m brother Tong, a hard core man who climbs 26 floors every day and doesn’t forget to read the source code. In the last section, we learned several symbols to represent the complexity. We said that […]

• ## Brush leetcode series with 233 sauce

Time：2021-3-18

PS: I give myself a nickname. You can call me 233 sauce Why brush leetcode To quote from the left ear mouse uncle mouse: ““ The questions on leetcode are used by some classic companies to interview candidates. Many people use these questions to apply for companies that like interview algorithms, such as Google, Microsoft, […]

• ## Update: all recursion can be rewritten as non recursion?

Time：2021-3-8

preface This article is included in the album:http://dwz.win/HjK, click to unlock more knowledge of data structure and algorithm. Hello, I’m brother Tong, a hard core man who climbs 26 floors every day and doesn’t forget to read the source code. In the previous section, we used bitmap to introduce the implementation of 12306 ticket grabbing […]

• ## How to query the historical stock price of a stock?

Time：2021-2-5

A small tool that can query the historical stock price online. At present, it can query the historical stock prices of a shares, Hong Kong shares and U.S. stocks. In addition, it can download the historical stock price excel of individual stocks, which is very useful for analysis and research Download in two steps: Fill […]

• ## Liang Xu was arranged by a million big V, and took a picture with Miss Beauty

Time：2020-10-23

Hello, I’m Liang Xu. Many people asked me, “Liang Xu,What time did you spend so much time and energy on writing the official account from the media? In fact, the reason is very simple. I want to do a sideline job. If I really lose my job when I’m 35, I have at least another […]

• ## Join me – react native – join Redux’s todolinist

Time：2020-10-17

Before reading This project is the first time to use the example of Redux and does not have professional theoretical knowledge. Share the development process and experience. Before that, I wrote a small blog post about react native todolist that didn’t join redux. This project is also completed on the basis of the original decoration. […]

• ## [go] the best set of options

Time：2020-10-5

background When you write a struct in go, you often encounter setting functions for each field in the struct. This question seems very simple and easy. In fact, it bothers many people. Even rob pike, one of the three go giants, has been troubled by it for a while. Later, he found out the best […]

• ## [reprint] cache update routine

Time：2020-6-18

When you see a lot of people writing code to update cached data,Delete the cache before updating the database, and subsequent operations will reload the data into the cache.However, the logic is wrong。 Imagine two concurrent operations, one is the update operation, the other is the query operation. After the update operation deletes the cache, […]