Introduction to DSA

🔹 Encapsulation

**Encapsulation** is one of the fundamental principles of **Object-Oriented Programming (OOP)**. It is the concept of **hiding the internal details** of an object and only exposing the necessary parts through a controlled interface.

📌 Why Use Encapsulation?

Encapsulation helps in **data protection, modularity, and maintainability**.

✅ **Data Hiding** – Prevents direct modification of internal data.
✅ **Improves Security** – Restricts access to sensitive information.
✅ **Enhances Maintainability** – Changes can be made internally without affecting external code.

💡 Real-Life Example

Consider a **Bank Account** where the balance should not be directly accessible. Instead, we provide **getter and setter methods** to control access.

🖥️ Encapsulation in Java

In Java, we achieve encapsulation by using **private variables** and **public methods**.


            class BankAccount {
                private double balance;
                
                public BankAccount(double balance) {
                    this.balance = balance;
                }
                
                public double getBalance() {
                    return balance;
                }
                
                public void deposit(double amount) {
                    if (amount > 0) {
                        balance += amount;
                    }
                }
            }
            
            public class Main {
                public static void main(String[] args) {
                    BankAccount account = new BankAccount(1000);
                    account.deposit(500);
                    System.out.println("Balance: " + account.getBalance());
                }
            }

🖥️ Encapsulation in Python

In Python, encapsulation is implemented using **private attributes** (prefixing with **_ or __**).


            class BankAccount:
                def __init__(self, balance):
                    self.__balance = balance
                
                def get_balance(self):
                    return self.__balance
                
                def deposit(self, amount):
                    if amount > 0:
                        self.__balance += amount
            
            account = BankAccount(1000)
            account.deposit(500)
            print("Balance:", account.get_balance())

🎯 Summary