Home Backend Development C++ The difference between const in c and c++

The difference between const in c and c++

Apr 28, 2024 pm 06:30 PM
c++ Scope

In C and C, the const keyword is used to declare constants. In C, const can only modify variables, not pointers or arrays; in C, const can modify variables, pointers, and arrays. The main differences are: scope, pointer modification, and initialization requirements.

The difference between const in c and c++

Difference between const in C and C

const keyword

const is a type qualifier in C and C that is used to declare constants. Constants are values ​​that cannot be modified during program execution.

const in C

  • In C, const can only modify ordinary variables, not pointers or arrays.
  • Variables modified by const must be initialized when declared.
  • const variables can be modified indirectly through pointers.

const in C

  • const in C can modify variables, pointers and arrays.
  • In C, const can be declared as one of two types:

    • const variable: a value that cannot be modified.
    • const pointer: a pointer to a variable whose value cannot be modified.
  • In C, const variables cannot be modified indirectly through pointers.

Main Differences

The following are the main differences between const in C and const in C:

  • Scope: In C, const can only modify ordinary variables, but in C, it can modify variables, pointers and arrays.
  • Pointer modification: In C, const variables can be modified indirectly through pointers, but in C, this is not allowed.
  • Initialization: In C, const variables must be initialized when declared, while in C, there is no such requirement.

The above is the detailed content of The difference between const in c and c++. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

Repo: How To Revive Teammates
1 months ago By 尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
1 months ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

How to implement the Strategy Design Pattern in C++? How to implement the Strategy Design Pattern in C++? Jun 06, 2024 pm 04:16 PM

The steps to implement the strategy pattern in C++ are as follows: define the strategy interface and declare the methods that need to be executed. Create specific strategy classes, implement the interface respectively and provide different algorithms. Use a context class to hold a reference to a concrete strategy class and perform operations through it.

How to implement nested exception handling in C++? How to implement nested exception handling in C++? Jun 05, 2024 pm 09:15 PM

Nested exception handling is implemented in C++ through nested try-catch blocks, allowing new exceptions to be raised within the exception handler. The nested try-catch steps are as follows: 1. The outer try-catch block handles all exceptions, including those thrown by the inner exception handler. 2. The inner try-catch block handles specific types of exceptions, and if an out-of-scope exception occurs, control is given to the external exception handler.

How to use C++ template inheritance? How to use C++ template inheritance? Jun 06, 2024 am 10:33 AM

C++ template inheritance allows template-derived classes to reuse the code and functionality of the base class template, which is suitable for creating classes with the same core logic but different specific behaviors. The template inheritance syntax is: templateclassDerived:publicBase{}. Example: templateclassBase{};templateclassDerived:publicBase{};. Practical case: Created the derived class Derived, inherited the counting function of the base class Base, and added the printCount method to print the current count.

How to handle cross-thread C++ exceptions? How to handle cross-thread C++ exceptions? Jun 06, 2024 am 10:44 AM

In multi-threaded C++, exception handling is implemented through the std::promise and std::future mechanisms: use the promise object to record the exception in the thread that throws the exception. Use a future object to check for exceptions in the thread that receives the exception. Practical cases show how to use promises and futures to catch and handle exceptions in different threads.

Why does an error occur when installing an extension using PECL in a Docker environment? How to solve it? Why does an error occur when installing an extension using PECL in a Docker environment? How to solve it? Apr 01, 2025 pm 03:06 PM

Causes and solutions for errors when using PECL to install extensions in Docker environment When using Docker environment, we often encounter some headaches...

Quantitative currency trading software Quantitative currency trading software Mar 19, 2025 pm 04:06 PM

This article explores the quantitative trading functions of the three major exchanges, Binance, OKX and Gate.io, aiming to help quantitative traders choose the right platform. The article first introduces the concepts, advantages and challenges of quantitative trading, and explains the functions that excellent quantitative trading software should have, such as API support, data sources, backtesting tools and risk control functions. Subsequently, the quantitative trading functions of the three exchanges were compared and analyzed in detail, pointing out their advantages and disadvantages respectively, and finally giving platform selection suggestions for quantitative traders of different levels of experience, and emphasizing the importance of risk assessment and strategic backtesting. Whether you are a novice or an experienced quantitative trader, this article will provide you with valuable reference

How does C++ memory management optimize memory usage? How does C++ memory management optimize memory usage? Jun 05, 2024 pm 10:41 PM

Optimization techniques for C++ memory management include: using smart pointers (RAII), reducing frequent allocations, avoiding unnecessary copies, using low-level APIs (with caution), and analyzing memory usage. Through these techniques, such as using smart pointers and caching in image processing applications, memory usage and performance can be significantly optimized.

How do C++ Lambda expressions improve performance? How do C++ Lambda expressions improve performance? Jun 06, 2024 am 11:35 AM

Yes, Lambda expressions can significantly improve C++ performance because it allows functions to be passed as variables and eliminates the overhead of function calls through inline unrolling, such as: Inline unrolling optimization: inserting code directly into the calling location, eliminating function call overhead . Lightweight functions: Lambda expressions are typically more lightweight than regular functions, further reducing overhead. Practical example: In the sorting algorithm, Lambda expressions eliminate comparison function calls and improve performance. Other usage scenarios: as callback function, data filtering and code simplification. Caveats: Capture variables carefully, consider memory usage, and avoid overuse to maintain readability.

See all articles