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Programmation

How to Start C++ Programming in 2026

12 minBEGINNER
DébutantC++
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Introduction

C++ remains an essential language in 2026 for systems, games, and high-performance applications. This tutorial guides you step by step from installation to creating simple functions. Each concept comes with a complete, compilable example. You will learn to write clean code and avoid classic mistakes right from the beginning.

Prerequisites

  • Computer running Windows, macOS, or Linux
  • Basic computer knowledge
  • Terminal or command prompt

Installing the Compiler

terminal
# Linux (Ubuntu/Debian)
sudo apt update && sudo apt install g++

# macOS
xcode-select --install

# Windows : installer MinGW ou MSYS2

This command installs the g++ compiler required to convert C++ code into an executable. Verify the installation with g++ --version before proceeding.

First Hello World Program

main.cpp
#include <iostream>

int main() {
    std::cout << "Hello, C++ 2026 !" << std::endl;
    return 0;
}

This file contains the minimal program. Compile it with g++ main.cpp -o hello and run ./hello to see the message displayed.

Declaring Variables

variables.cpp
#include <iostream>
#include <string>

int main() {
    int age = 25;
    double prix = 19.99;
    std::string nom = "Alice";
    std::cout << nom << " a " << age << " ans." << std::endl;
    return 0;
}

The code declares and uses three basic types. Compile and run it to observe the formatted output. Avoid using overly short variable names.

Using Loops

boucles.cpp
#include <iostream>

int main() {
    for(int i = 1; i <= 5; i++) {
        std::cout << "Itération : " << i << std::endl;
    }
    return 0;
}

The for loop displays 5 iterations. Experiment by modifying the condition to understand its behavior.

Creating a Function

fonction.cpp
#include <iostream>

int addition(int a, int b) {
    return a + b;
}

int main() {
    int resultat = addition(8, 12);
    std::cout << "Résultat : " << resultat << std::endl;
    return 0;
}

The addition function takes two parameters and returns their sum. Call it from main to easily reuse the code.

Best Practices

  • Always initialize variables
  • Use descriptive names
  • Compile with the -Wall flag to see warnings
  • Separate declarations and implementations in larger projects

Common Mistakes to Avoid

  • Forgetting the semicolon at the end of statements
  • Missing necessary header includes
  • Exceeding array bounds
  • Ignoring compiler warning messages

Further Learning

Deepen your skills with our complete C++ courses.