Programmer Think

Reading guide In the previous chapters, we introduced how to operate excel and ppt in batches. Today, we talk about the batch operation of word documents application Python docx allows you to create new documents and make changes to existing documents. In fact, it only allows you to make changes to existing documents; But if you start ...

1.caffeine features Caffeine uses ConcurrentHashMap internally, provides a variety of cache elimination mechanisms (according to time, weight, quantity, etc.), and supports elimination notification. Moreover, caffeine has high cache performance on the premise of ensuring thread safety, which is known as the king of cache 1.1 official performa ...

Some codes involve the knowledge mentioned before Quick sort Two way fast platoon Improve according to the one-way fast sorting in the previous section. In order to prevent each cycle, the same number is on one side, such as: 3 4 1 2 3 2 1 3 1 3 5 4 Single way fast platoon: 1 1 2 1 3 3 3 4 5 4 In this way, the case equal to thre ...

Change The most direct solution to the change problem is the greedy strategy. For example: for coins with face values of 1, 5, 10 and 25, solve the minimum number of coins required to exchange 63 yuan. The idea of greedy strategy is to constantly use the coins with the largest face value to try. No, in this case, 25 coins are used to try the ...

Object class Object is the top-level superclass of all classes. There are two methods that are often overridden by subclasses: toString() and equals() package object; /** * Object Is the top superclass of all classes There are several methods that are often overridden by subclasses, including toString and equals */ public class Demo { ...

Annotation programming 01 what is annotation programming :::info It refers to adding specific annotations to classes or methods to complete the development of specific functionsThe use of annotations is convenient for development, the code is concise, and the development speed is greatly provided ::: 02 role of annotations :::success ...

generic paradigm Why use generics: Early Object types can accept any Object type, but in practical use, there will be the problem of type conversion. This hidden danger exists, so Java provides generics to solve this security problem What is generics: ● generic, i.e. "parameterized type". When referring to parameters, the most fam ...

support vector machine In the case of linear separability, the data point closest to the separation hyperplane in the sample points of the training data set is called support vector. The cost function and logistic regression are similar: Also known as large interval classifier, it can find the best linear classification position: The phys ...

ZooKeeper stand-alone installation The installation directory takes / opt/share/zk as an example Create a new directory / opt/share/zk. The command is as follows: mkdir -p /opt/share/zk Enter / opt/share/zk directory and upload jdk-8u301-linux-x64 tar. GZ file Unzip jdk-8u301-linux-x64.0 tar. GZ file, the command is as follows: tar -zxvf ...

background We have a regular task in a single project, which will query and calculate the scores and rankings of different users from each business table every other hour. It is realized by Quartz; This encountered a problem in the later horizontal expansion to multi instance cluster deployment: the scheduled task is repeatedly executed in mul ...