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Accuracy problems encountered by Golang in dealing with floating point numbers Golang easy learning 1, What is a floating point number? Floating point number is a digital representation of the number belonging to a special subset of rational numbers. It is used to approximately represent any real number in the computer. Floating poi ...

Stack memory and heap memory The declared variables and function names are stack memory, but heap memory is used in dynamic memory management. Stack memory is relatively compact, so it has large local correlation. There is a dynamic expansion in the heap during operation, and the release needs to be displayed. new is called at run time. ve ...

File summary: If you want to realize IO stream operation, you must know the representation of files on the hard disk Java provides a class that allows us to manipulate files on the hard disk: file. File is the representation of a file File: abstract representation of file and directory (folder) pathnames. Construction method of File class ...

preface "If you cannot measure it, you cannot improve it". In daily development, there are many options for calling some code or using tools. When we are not sure about their performance, the first thing we want to do is to measure it. Most of the time, we will simply use multiple counts to measure the total time-consuming of this method. Ho ...

*** Process control 1) Sequential structure: code is executed from top to bottom, and each statement is executed in sequence (default) 2) Branch structure: choose to execute or not execute part of the code according to the conditions (use if) 3) Loop structure: make the code execute repeatedly (for, while) Branching structure age = 10 if ag ...

1, Interface 1.1 what is the interface First of all, explain the rookie tutorial, which is very professional Interface (English: Interface), an abstract type in JAVA programming language, is a collection of abstract methods. Interfaces are usually declared as interfaces. A class inherits the abstract methods of the interface by inheritin ...

What is the transaction propagation mechanism The propagation mechanism of transactions, as the name suggests, is how to propagate transactions between multiple transaction methods. For example, method A is A transactional method. Method B is called when method A executes. Whether method B has A transaction or not and whether it needs A tr ...

open/close int fd2; fd2=open(argv[1],O_RDWR | O_CREAT | O_EXCL,0655); if(fd2==-1) { perror("open file error!"); exit(1); } printf("fd2=%d\n",fd2); int ret=close(fd2); printf("fd2=%d\n",fd2); printf("ret=%d\n",ret); Partial code O_RDONLY O_WRONLY O_RDWR: read only write only O_CREAT: create when the f ...

Reading needs a certain foundation, which is not suitable for people who first know Java. There are some concise languages, some knowledge points or a brush, and you don't know that you need to consult the materials in detail. The purpose of this article is to supplement some details of Java foundation, some slightly in-depth places and some pl ...

catalogue abnormal 1. Classification of anomalies 2. Two methods of handling exceptions try...catch...finally The difference between compile time exception and run-time exception: Methods in Throwable finally throws throw  The difference between throws and throw: abnormal Abnormal condition in Java program 1. Classification of ano ...