Programmer Think

preface In the previous study, we have been exposed to the output format of str.format(). In this section, we will further learn the relevant contents of string printout, and feel the convenience of using str.format() output through a series of small examples. practice Let's first define two variables: animal = "cow" item = "moon" If ...

In the last section, we talked about flex. Today, we talk about bison flex is used to analyze morphology, such as your keywords and operation symbols. bison is used to analyze grammar, that is, the grammar method you define, that is, the meaning you need to express after arranging the keywords and symbols you define according to a certain form ...

background In the process of database design, we often add some general fields to database tables, such as creator, creation time, modifier and modification time. Sometimes, in the design process of some companies, each table is forced to contain these basic information in order to record some basic log records during data operation. According ...

R language is a mathematical programming language designed for mathematical researchers. It is mainly used for statistical analysis, drawing and data mining. R language is a language for interpretation and operation (different from the compilation and operation of C language). Its execution speed is much slower than C language, which is not con ...

Python function decorator Occasionally, you will see the following forms of code in python: @functionA def functionB(): ... return So what is the role of @ functionA? First answer: @functionA <=> functionB = functionA(functionB) The following is an explanation through a case. If there are deficiencies, you are welcome to correc ...

Understanding of Java loading and execution: There are two very important stages of java programs: Compile phase: the source file will be java becomes a bytecode file class (compiling is essentially checking whether the syntax is correct) Run phase: the JVM will load the bytecode file and interpret the bytecode Basic data type Basic data ty ...

preface: DDD is an architectural idea, not a framework. Domain Primitive: What is DP? It is the "basic data structure" in DDD. Like int and string in Java, it is the only way for us to learn. It's a little abstract. Let's illustrate it through a case. For the user registration function, you need to enter the user's name, telephone ...

Problem: two billboards and five advertisers design an algorithm. The number of advertisements of five advertisers in a period of time is 1:2:3:4:5. Note that two billboards cannot broadcast the same advertisement at the same time. Considering that there is only one billboard, you only need to select the corresponding advertisement according t ...

preface Now many companies are using HikariCP. HikariCP has also become the default connection pool of SpringBoot. With SpringBoot and microservices, HikariCP will be widely popularized. The blogger will take you to analyze why HikariCP is favored by Spring Boot from the perspective of source code. The article directory is as follows: Zero ...

1. Introduction2. PyPy installation configuration under Windows3. Special package4. Test 4.1. Test cycle4.2. numpy test 1. Introduction PyPy is a faster version of python The package used is exactly the same and the use method is exactly the same.However, not all packages in python are supported.Yes, for Python 3 7, Python2. 7. Ins ...