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Remodule of python built-in module

What is a rule? A regular expression, also known as a regular expression, is a special sequence of characters that helps check whether a string matches a pattern.Can be used for authentication: mailbox, mobile number, qq number, password, url =website address, ip, etc.Regular is not a unique technology for python. The Python language does not organize/incorporate regular expressions into the re module until version 1.5. All we need to...

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Java Design Mode-Policy Mode

Strategy mode: A series of algorithms can be defined to encapsulate them one by one. For example, a game has different recharge rates for different levels of members, Diamond members 1 yuan = 15 coins, Platinum members 1 yuan = 13 coins, and Gold members 1 yuan = 10 coins.This allows three algorithms of the three members to be encapsulated in separate implementation classes, and then three implementation classes implement the same...

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Java Design Mode-Policy Mode

Strategy mode: A series of algorithms can be defined to encapsulate them one by one. For example, a game has different recharge rates for different levels of members, Diamond members 1 yuan = 15 coins, Platinum members 1 yuan = 13 coins, and Gold members 1 yuan = 10 coins.This allows three algorithms of the three members to be encapsulated in separate implementation classes, and then three implementation classes implement the same...

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python3-cookbook notes: Chapter IX Metaprogramming

Each section in the python3-cookbook explores the best solution of Python 3 to a given problem in three parts: problem, solution, and discussion, or how Python 3's own data structure, functions, classes, and so on, can be better used in a given problem.This book is very helpful for understanding Python 3 and improving Python programming capabilities, especially for improving the performance of Python programs. It is strongly...

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Tear the bottom of the ArrayList by hand to thoroughly analyze the source code

Overview of ArrayList Hello, I'm going to talk about ArrayList today. When it comes to ArrayList, many people know that the bottom of it is implemented using arrays. Threads are not safe. When it comes to its features, it will say that search is fast and increase or decrease slowly, because interview questions are all reciprocal.Let's talk about its underlying source today. ArrayList is more precisely implemented by dynamic arrays,...