What are the typical usage scenarios of C++ function pointers?

In C, the char type is used in strings: 1. Store a single character; 2. Use an array to represent a string and end with a null terminator; 3. Operate through a string operation function; 4. Read or output a string from the keyboard.

The calculation of C35 is essentially combinatorial mathematics, representing the number of combinations selected from 3 of 5 elements. The calculation formula is C53 = 5! / (3! * 2!), which can be directly calculated by loops to improve efficiency and avoid overflow. In addition, understanding the nature of combinations and mastering efficient calculation methods is crucial to solving many problems in the fields of probability statistics, cryptography, algorithm design, etc.

Multithreading in the language can greatly improve program efficiency. There are four main ways to implement multithreading in C language: Create independent processes: Create multiple independently running processes, each process has its own memory space. Pseudo-multithreading: Create multiple execution streams in a process that share the same memory space and execute alternately. Multi-threaded library: Use multi-threaded libraries such as pthreads to create and manage threads, providing rich thread operation functions. Coroutine: A lightweight multi-threaded implementation that divides tasks into small subtasks and executes them in turn.

std::unique removes adjacent duplicate elements in the container and moves them to the end, returning an iterator pointing to the first duplicate element. std::distance calculates the distance between two iterators, that is, the number of elements they point to. These two functions are useful for optimizing code and improving efficiency, but there are also some pitfalls to be paid attention to, such as: std::unique only deals with adjacent duplicate elements. std::distance is less efficient when dealing with non-random access iterators. By mastering these features and best practices, you can fully utilize the power of these two functions.

In C language, snake nomenclature is a coding style convention, which uses underscores to connect multiple words to form variable names or function names to enhance readability. Although it won't affect compilation and operation, lengthy naming, IDE support issues, and historical baggage need to be considered.

The release_semaphore function in C is used to release the obtained semaphore so that other threads or processes can access shared resources. It increases the semaphore count by 1, allowing the blocking thread to continue execution.

Exploring Undefined Behaviors in C Programming: A Detailed Guide This article introduces an e-book on Undefined Behaviors in C Programming, a total of 12 chapters covering some of the most difficult and lesser-known aspects of C Programming. This book is not an introductory textbook for C language, but is aimed at readers familiar with C language programming, and explores in-depth various situations and potential consequences of undefined behaviors. Author DmitrySviridkin, editor Andrey Karpov. After six months of careful preparation, this e-book finally met with readers. Printed versions will also be launched in the future. This book was originally planned to include 11 chapters, but during the creation process, the content was continuously enriched and finally expanded to 12 chapters - this itself is a classic array out-of-bounds case, and it can be said to be every C programmer

C language conditional compilation is a mechanism for selectively compiling code blocks based on compile-time conditions. The introductory methods include: using #if and #else directives to select code blocks based on conditions. Commonly used conditional expressions include STDC, _WIN32 and linux. Practical case: Print different messages according to the operating system. Use different data types according to the number of digits of the system. Different header files are supported according to the compiler. Conditional compilation enhances the portability and flexibility of the code, making it adaptable to compiler, operating system, and CPU architecture changes.