Introduction to C++

C++ is a general-purpose, object-oriented programming language developed by Bjarne Stroustrup in 1985. It is an extension of the C language and is widely used for system programming, game development, and applications requiring high performance.

Key Features of C++:

Object-Oriented: C++ supports OOP principles like encapsulation, inheritance, and polymorphism.
Efficient: C++ provides low-level memory manipulation and high performance.
Rich Standard Library: C++ has a vast collection of built-in functions and templates.
Portable: C++ programs can run on different platforms with minimal changes.
Multi-Paradigm: C++ supports procedural, object-oriented, and generic programming.

Example: Hello World in C++


// C++ Hello World Program
#include <iostream>

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

This program includes the iostream library and uses the std::cout object to print "Hello, World!" to the console.

Object-Oriented Programming (OOP) in C++

C++ is designed to support object-oriented programming, which organizes software design around data (objects) rather than functions and logic. Key OOP concepts in C++ include:

Classes and Objects: Classes are user-defined data types, and objects are instances of classes.
Encapsulation: Bundling data and methods that operate on the data within a single unit.
Inheritance: Creating new classes from existing ones to promote code reuse.
Polymorphism: Allowing objects to be treated as instances of their parent class.


#include <iostream>

// Define a class
class Animal {
public:
    void speak() {
        std::cout << "Animal speaks!" << std::endl;
    }
};

// Inherit from the Animal class
class Dog : public Animal {
public:
    void speak() {
        std::cout << "Dog barks!" << std::endl;
    }
};

int main() {
    Animal myAnimal;
    Dog myDog;

    myAnimal.speak();  // Output: Animal speaks!
    myDog.speak();     // Output: Dog barks!
    return 0;
}

Standard Template Library (STL)

The STL is a powerful library in C++ that provides a collection of template classes and functions. It includes:

Containers: Data structures like vectors, lists, and maps.
Algorithms: Functions for sorting, searching, and manipulating data.
Iterators: Objects used to traverse containers.


#include <iostream>
#include <vector>
#include <algorithm>

int main() {
    std::vector<int> numbers = {5, 2, 9, 1, 5, 6};

    // Sort the vector
    std::sort(numbers.begin(), numbers.end());

    // Print the sorted vector
    for (int num : numbers) {
        std::cout << num << " ";
    }
    return 0;
}

Best Practices

Use Descriptive Names: Choose meaningful names for variables, functions, and classes.
Follow OOP Principles: Encapsulate data, use inheritance wisely, and leverage polymorphism.
Use STL: Prefer STL containers and algorithms for common tasks.
Memory Management: Use smart pointers (std::unique_ptr, std::shared_ptr) to manage dynamic memory safely.
Error Handling: Use exceptions to handle errors gracefully.

Next: Variables and Data Types