CPP Tutorial

🏗️ Structure of a C++ Program

Every C++ program has a basic structure that helps the compiler understand what to do. Let’s break down the parts of a simple C++ program.

Key Parts of a C++ Program

1. Preprocessor Directive
   This tells the compiler to include certain libraries before compiling the code.
   Example: #include <iostream> lets you use input-output functions.
2. Namespace
   It helps avoid naming conflicts by grouping entities. Usually, using namespace std; is used to access standard functions easily.
3. Main Function
   Every C++ program starts executing from int main(). It is the entry point of the program.
4. Statements
   Instructions inside main() that perform tasks, like printing output.
5. Return Statement
   return 0; indicates the program ended successfully.

Example: Simple C++ Program Structure

#include <iostream>                 // Preprocessor directive

using namespace std;                // Namespace

int main() {                       // Main function
  cout << "Welcome to C++!"; // Output statement
  return 0;                        // Return statement
}
  

Explanation

• #include <iostream> includes standard input-output stream library.
• using namespace std; allows you to use standard functions like cout without prefixing std::.
• int main() is the starting point of every program.
• cout prints the message Welcome to C++! on the screen.
• return 0; signals that the program ended without errors.

Summary

The basic structure of a C++ program includes a preprocessor directive, namespace, main function, executable statements, and a return statement. This simple framework helps in building complex programs.