Solution to “Python3.12pip network installation library file error, ssl module is unavailable” 1. Install the new version of openssl3.1.4 2. Install Python3.12.0 The Python version needs to match the openssl version. In versions after Python 3.7, the dependent openssl must be a version after 1.1.1 or 1.0.2, and the openssl1.0.2k installed in CentOS7 cannot meet […]
Tag: sta
Thread status and thread safety issues
Article directory Thread status All states of the thread Thread state transition Multi-threading vs. Single-thread Efficiency Improvement Risks of Multithreading – Thread Safety Issues Case analyze reason Solution synchronized keyword – monitor lock Use the synchronized keyword Features of synchronized mutually exclusive reentrant Thread-safe classes in the Java standard library deadlock What is deadlock Three […]
Understanding Crontab in Linux With Examples
The crontab is used to automate all types of tasks on Linux systems. This is an especially important skill for aspiring system administrators to learn. It can be somewhat challenging to get started if you’re a beginner. The syntax is different than most other commands. For this reason, this lesson will include a little more […]
One Demo handles the front-end and back-end multi-part uploading of large files, resumed uploading at breakpoints, and instantaneous uploading.
1Foreword File uploading is very common in project development. Most projects will involve the uploading of pictures, audios, videos, and files. Usually a simple Form can upload small files, but when encountering large files, such as more than 1GB, or When the user’s network is relatively slow, simple file upload is not applicable. The user […]
LC-1334. The city with the fewest neighbors within the threshold distance (Floyd algorithm, memorized search ==> dynamic programming (0x3f))
1334. The city with the fewest neighbors within the threshold distance medium There are n cities, numbered from 0 to n-1. Give you an edge array edges, where edges[i] = [fromi, toi, weighti] represents fromi and toi code> A bidirectional weighted edge between two cities, the distance threshold is an integer distanceThreshold. Returns the city […]
[Data structure] Simulation implementation of stack and queue (implemented in two ways)
Foreword About the author: Come on, Xu Xing, currently a sophomore, currently learning C++, Data Structure, etc. Author’s homepage: Come on, Xu Xing’s homepage ?This article is included in: Re-recognizing the advanced column of C Code Warehouse: Rising Sun 1 Everyone is welcome to like Collect ? Follow! Learning objectives: This blog will learn about […]
Linux file operations – standard c library for file operations
The difference between Linux and standard c library in file operations 1. Source From the perspective of source, the two can be distinguished very well, and this is also the most obvious difference between the two: open is a UNIX system call function (including LINUX, etc.). It returns a file descriptor (File Descriptor), which is […]
Use the Stream stream to convert the obtained object List<Object>form data into Map<Grouping conditions, quantity statistics>form
For example, the current business needs to group the obtained data, and then use another method to process the data. The methods used are Collectors.groupingBy, Collectors.counting(), Collectors.reducing(). Then, take the following example as an example to collect the obtained lists and group the obtained data by gender, with gender as K and the number of […]
Instances of all methods in the list type (except sort) and explanations (called through help (list))
1. Overview After using help (list) and running it, you can see the following methods: append, clear, copy, count, extend, index, insert, pop, remove, reverse, a total of ten methods. Next, I will give examples one by one. explain. 2. Examples and explanations 1.append: Append object to the end of the list. (Append object to […]
About dpkg packaged into deb format installation package
The deb format is suitable for operating systems such as Ubuntu, deepin, and UOS, and for servers with various architectures such as mips64el, amd64, and X86. Ubuntu uses dpkg to make the qt executable program into a deb installation package1. Use the linuxdeployqt tool to package the executable program This step can package the dynamic […]