Learn C++

C++ Introduction

C++ is a general-purpose programming language developed by Bjarne Stroustrup. It is an extension of the C language with object-oriented features, making it suitable for system-level programming, game development, and applications requiring high performance.

Key Features

• Object-Oriented Programming (OOP)
• Standard Template Library (STL)
• Memory Management (pointers, dynamic allocation)
• Multi-paradigm (procedural, functional, object-oriented)

IDE (Integrated Development Environment)

An IDE is a software application that provides comprehensive facilities for software development. Popular IDEs for C++ include:

• Visual Studio Code
• Code::Blocks
• Eclipse
• JetBrains CLion

Features

• Code Editor
• Debugger
• Compiler Integration
• IntelliSense (code suggestions)

Compiler

A compiler translates human-readable C++ code into machine code. Popular C++ compilers:

• GCC (GNU Compiler Collection)
• Clang
• Microsoft Visual C++ Compiler

Downloading Visual Studio Code

Visual Studio Code is a lightweight, powerful code editor with extensive extensions for C++ programming.

Steps to Download

1. Visit the official website.
2. Download the version appropriate for your operating system.
3. Install the downloaded file.

Downloading, Installing & Configuring Compiler

Steps

1. Download GCC using MinGW or a similar tool.
   • For Windows, use MinGW-w64.
2. Install MinGW and add its bin directory to the system PATH.
3. Test installation by typing g++ --version in the terminal.

Installing VS Code

1. Open the VS Code installer and follow the on-screen instructions.
2. Install the C/C++ extension from the Extensions Marketplace.
3. Configure the tasks.json and launch.json files for building and debugging.

Basics of VS Code

• Explorer: View and manage project files.
• Editor: Write and edit code.
• Terminal: Execute commands.
• Extensions: Add new features like IntelliSense and debugging tools.

Writing First C++ Program

Code

#include <iostream>
using namespace std;

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

Steps

1. Open a new file in VS Code.
2. Save it with a .cpp extension.
3. Compile using g++ filename.cpp -o filename.
4. Run the executable using ./filename.

Understanding First Program

• #include <iostream>: Includes the library for input/output.
• using namespace std;: Avoids prefixing standard library functions with std::.
• int main(): Entry point of the program.
• cout: Outputs text to the console.
• return 0;: Indicates successful program termination.

Comments

• Single-line comment: // This is a comment
• Multi-line comment:

/* This is
   a multi-line
   comment */

Data Types in C++

Primitive Types

• int, float, double, char, bool

Derived Types:

• Arrays, Functions, Pointers User-defined Types:
• Structures, Classes, Enums

Variables

A variable is a container for storing data.

Syntax

int number = 10;
float pi = 3.14;
char grade = 'A';

Taking User Input

Code

#include <iostream>
using namespace std;

int main() {
    int age;
    cout << "Enter your age: ";
    cin >> age;
    cout << "Your age is " << age << endl;
    return 0;
}

Operators

1. Arithmetic: +, -, *, /, %
2. Relational: ==, !=, >, <, >=, <=
3. Logical: &&, ||, !

If-Else Statements

Code

if (condition) {
    // code block
} else {
    // code block
}

Switch Statement

Code

switch (variable) {
    case value1:
        // code block
        break;
    case value2:
        // code block
        break;
    default:
        // code block
}

Loops

1. For Loop

for (int i = 0; i < 5; i++) {
    cout << i << endl;
}

2. While Loop

while (condition) {
    // code block
}

3. Do-While Loop

do {
    // code block
} while (condition);

Functions

Syntax

returnType functionName(parameters) {
    // code block
    return value;
}

Arrays

An array stores multiple values of the same type.

int arr[5] = {1, 2, 3, 4, 5};

Typecasting

Converting one data type to another.

float num = 10.5;
int integer = (int)num;

Strings

Strings are objects in C++.

#include <string>
string str = "Hello";

Pointers

A pointer stores the address of a variable.

int var = 10;
int* ptr = &var;

Objects & Classes

C++ is object-oriented, using classes and objects.

Class

class Car {
public:
    string brand;
    void display() {
        cout << brand;
    }
};

Object

Car car1;
car1.brand = "Toyota";
car1.display();

Constructor

Special method called when an object is created.

class Car {
public:
    string brand;
    Car(string b) {
        brand = b;
    }
};

Inheritance

A way to derive one class from another.

class Parent {
public:
    void display() {
        cout << "Parent Class";
    }
};

class Child : public Parent {
};