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Operator arithmetic operator + plus-reduce*ride/except%Remainder (operand must be an integer) Arithmetic conversion: char -> int -> float -> double Shift operators Data storage: binary complement <<Shift left (discard on the left and fill zero on the right)>> Shift right (1) logical shift: fill zero on the lef ...

  Here is only for personal notes. The content and code are mostly from the 100 day course of GitHub Luo Hao God. The link is attached below, which is infringed and deleted~ GitHub - jackfried / python-100-days: Python - 100 days from novice to master 1, Use of functions and modules (1) Define function: use the def keyword to define a f ...

1. In the experiment, use the debug function of IDE to set breakpoints for the new statements of examples 6.4 and 6.5, use step into / step over to track the execution sequence of subclass object instantiation (initialization), and summarize the process Example 6.4 //Example 6.4: explicitly using super to call the constructor of the parent cl ...

1.IOC control reversal IOC theoretical derivation Previous methods 1. First write a UserDao interface public interface UserDao { public void getUser(); } 2. Then write Dao's implementation class public class UserDaoImpl implements UserDao { @Override public void getUser() { System.out.println("Get user data"); } } 3. ...

Learning summary on September 28 1, Function basis 1. Cognitive function a. Concept (machine): a function is the encapsulation of code that implements a specific function b. Classification of functions 1. System functions (machines built by the system) - functions created by Python, such as print,input,type,max,min,id, etc 2. User defined ...

Let's start with two concepts: process and thread            Process: a running program, which is an independent unit of the system for resource allocation and call. Each process has its own memory space and system resources.          Thread: a single sequent ...

Representation and processing of information The three most important numbers represent: Unsigned( unsigned)Coding is based on the traditional binary representation, which represents numbers greater than or equal to zero. Complement( two' s-complement)Coding is the most common way to represent signed integers. Signed integers are numbers ...

1, Foreword Long time no see. How are you? Recently started learning Ruoyi Framework: a background management system based on SpringBoot. As a rapid development framework, online evaluation is good. Students who have time can look at the code and learn it. At the beginning, I planned to introduce the user-defined annotation with the Log ...

background Before Java introduces generics, programmers can build a collection with element type Object, which can store any data type Object. In the process of using this collection, programmers need to know the data type of each element, otherwise ClassCastException is easy to occur. Such as the following cases: package fanxing; impor ...

Create pattern Singleton mode Singleton Pattern is one of the simplest design patterns in Java. This type of design pattern is a creation pattern, which provides the best way to create objects. This pattern involves a single class that is responsible for creating its own objects while ensuring that only a single object is created. This clas ...