diff --git a/Assignment-2/Problem-1.java b/Assignment-2/Problem-1.java
new file mode 100644
index 0000000..f95e4d8
--- /dev/null
+++ b/Assignment-2/Problem-1.java
@@ -0,0 +1,27 @@
+public class Calculate {
+    int firstOperand;
+    double secondOperand;
+    String convertedUppercaseText;
+
+    public void printCalculatedSum(int firstOperand, int secondOperand) {
+        int additionResult = firstOperand + secondOperand;
+        System.out.println("Result: " + additionResult);
+    }
+
+    public void printUpperCaseString(String inputText) {
+        convertedUppercaseText = inputText.toUpperCase();
+        System.out.println("Updated String: " + convertedUppercaseText);
+    }
+}
+
+public class Computation {
+    public static void main(String[] args) {
+        Calculate calculate = new Calculator();
+        calculate.firstOperand = 10; 
+        calculate.secondOperand = 20.5; 
+        calculate.convertedUppercaseText = "hello"; 
+
+        calculate.printCalculatedSum(calculate.firstOperand, 5);
+        calculate.printUpperCaseString("world");
+    }
+}
diff --git a/Assignment-2/Problem-2.java b/Assignment-2/Problem-2.java
new file mode 100644
index 0000000..fd9375a
--- /dev/null
+++ b/Assignment-2/Problem-2.java
@@ -0,0 +1,97 @@
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+
+class Product {
+    private String name;
+    private double price;
+    private int quantity;
+
+    public setProductDetails(String name, double price, int quantity) {
+        this.name = name;
+        this.price = price;
+        this.quantity = quantity;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public double getPrice() {
+        return price;
+    }
+
+    public int getQuantity() {
+        return quantity;
+    }
+
+    public void setQuantity(int newQuantity) {
+        this.quantity = newQuantity;
+    }
+}
+
+class InventoryManager {
+    private List<Product> inventory;
+
+    public InventoryManager() {
+        this.inventory = new ArrayList<>();
+    }
+
+    public void addProduct(Product product) {
+        inventory.add(product);
+    }
+
+    public List<Product> getInventory() {
+        return inventory;
+    }
+}
+
+public class Main {
+    public static void main(String[] args) {
+        InventoryManager inventoryManager = new InventoryManager();
+        Scanner scanner = new Scanner(System.in);
+
+        while (true) {
+            System.out.println("\nInventory Management System");
+            System.out.println("1. Add Product");
+            System.out.println("2. Display Inventory");
+            System.out.println("3. Exit");
+            System.out.print("Enter your choice: ");
+
+            int userChoice = scanner.nextInt();
+
+            switch (userChoice) {
+                case 1:
+                    System.out.print("Enter product name: ");
+                    String productName = scanner.next();
+                    System.out.print("Enter product price: ");
+                    double productPrice = scanner.nextDouble();
+                    System.out.print("Enter product quantity: ");
+                    int productQuantity = scanner.nextInt();
+
+                    Product newProduct = new Product(productName, productPrice, productQuantity);
+                    inventoryManager.addProduct(newProduct);
+
+                    System.out.println("Product added successfully!");
+                    break;
+
+                case 2:
+                    System.out.println("\nCurrent Inventory:");
+                    List<Product> products = inventoryManager.getInventory();
+                    for (Product product : products) {
+                        System.out.println("Name: " + product.getName() +
+                                ", Price: $" + product.getPrice() +
+                                ", Quantity: " + product.getQuantity());
+                    }
+                    break;
+
+                case 3:
+                    System.out.println("Exiting program. Goodbye!");
+                    System.exit(0);
+
+                default:
+                    System.out.println("Invalid choice. Please enter a valid option.");
+            }
+        }
+    }
+}
diff --git a/Assignment-3/OCP/Device.java b/Assignment-3/OCP/Device.java
new file mode 100644
index 0000000..7efd0c3
--- /dev/null
+++ b/Assignment-3/OCP/Device.java
@@ -0,0 +1,3 @@
+interface Device {
+    void displayDetails();
+}
diff --git a/Assignment-3/OCP/DeviceFactory.java b/Assignment-3/OCP/DeviceFactory.java
new file mode 100644
index 0000000..ccc7289
--- /dev/null
+++ b/Assignment-3/OCP/DeviceFactory.java
@@ -0,0 +1,3 @@
+interface DeviceFactory {
+    Device createDevice();
+}
diff --git a/Assignment-3/OCP/Laptop.java b/Assignment-3/OCP/Laptop.java
new file mode 100644
index 0000000..3232c05
--- /dev/null
+++ b/Assignment-3/OCP/Laptop.java
@@ -0,0 +1,6 @@
+class Laptop implements Device {
+    @Override
+    public void displayDetails() {
+        System.out.println("Laptop: Model Y, RAM: 16GB, Storage: 512GB");
+    }
+}
diff --git a/Assignment-3/OCP/LaptopFactory.java b/Assignment-3/OCP/LaptopFactory.java
new file mode 100644
index 0000000..03c16ce
--- /dev/null
+++ b/Assignment-3/OCP/LaptopFactory.java
@@ -0,0 +1,6 @@
+class LaptopFactory implements DeviceFactory {
+    @Override
+    public Device createDevice() {
+        return new Laptop();
+    }
+}
diff --git a/Assignment-3/OCP/Main.java b/Assignment-3/OCP/Main.java
new file mode 100644
index 0000000..53cc17c
--- /dev/null
+++ b/Assignment-3/OCP/Main.java
@@ -0,0 +1,12 @@
+public class Main {
+    public static void main(String[] args) {
+        DeviceFactory smartphoneFactory = new SmartphoneFactory();
+        DeviceFactory laptopFactory = new LaptopFactory();
+
+        Device smartphone = smartphoneFactory.createDevice();
+        Device laptop = laptopFactory.createDevice();
+
+        smartphone.displayDetails();
+        laptop.displayDetails();
+    }
+}
diff --git a/Assignment-3/OCP/Smartphone.java b/Assignment-3/OCP/Smartphone.java
new file mode 100644
index 0000000..7d6651a
--- /dev/null
+++ b/Assignment-3/OCP/Smartphone.java
@@ -0,0 +1,6 @@
+class Smartphone implements Device {
+    @Override
+    public void displayDetails() {
+        System.out.println("Smartphone: Model X, RAM: 8GB, Storage: 128GB");
+    }
+}
diff --git a/Assignment-3/OCP/SmartphoneFactory.java b/Assignment-3/OCP/SmartphoneFactory.java
new file mode 100644
index 0000000..533e575
--- /dev/null
+++ b/Assignment-3/OCP/SmartphoneFactory.java
@@ -0,0 +1,6 @@
+class SmartphoneFactory implements DeviceFactory {
+    @Override
+    public Device createDevice() {
+        return new Smartphone();
+    }
+}
diff --git a/Assignment-3/SRP/problem-1/AreaCalculator.java b/Assignment-3/SRP/problem-1/AreaCalculator.java
new file mode 100644
index 0000000..2080307
--- /dev/null
+++ b/Assignment-3/SRP/problem-1/AreaCalculator.java
@@ -0,0 +1,5 @@
+public class AreaCalculator {
+    public double calculateArea(Rectangle rectangle) {
+        return rectangle.getLength() * rectangle.getWidth();
+    }
+}
diff --git a/Assignment-3/SRP/problem-1/Main.java b/Assignment-3/SRP/problem-1/Main.java
new file mode 100644
index 0000000..2672d63
--- /dev/null
+++ b/Assignment-3/SRP/problem-1/Main.java
@@ -0,0 +1,12 @@
+public class Main {
+    public static void main(String[] args) {
+        Rectangle rectangle = new Rectangle(5.0, 3.0);
+        AreaCalculator calculator = new AreaCalculator();
+        double area = calculator.calculateArea(rectangle);
+        printArea(area);
+    }
+
+    public static void printArea(double area) {
+        System.out.println("Area: " + area);
+    }
+}
diff --git a/Assignment-3/SRP/problem-1/Rectangle.java b/Assignment-3/SRP/problem-1/Rectangle.java
new file mode 100644
index 0000000..b574d89
--- /dev/null
+++ b/Assignment-3/SRP/problem-1/Rectangle.java
@@ -0,0 +1,17 @@
+public class Rectangle {
+    private double length;
+    private double width;
+
+    public Rectangle(double length, double width) {
+        this.length = length;
+        this.width = width;
+    }
+
+    public double getLength() {
+        return length;
+    }
+
+    public double getWidth() {
+        return width;
+    }
+}
diff --git a/Assignment-3/SRP/problem-2/AreaFileCalculator.java b/Assignment-3/SRP/problem-2/AreaFileCalculator.java
new file mode 100644
index 0000000..d29f171
--- /dev/null
+++ b/Assignment-3/SRP/problem-2/AreaFileCalculator.java
@@ -0,0 +1,12 @@
+import java.io.FileWriter;
+import java.io.IOException;
+
+public class AreaFileWriter {
+    public void writeAreaToFile(double area) {
+        try (FileWriter writer = new FileWriter("area.txt")) {
+            writer.write("Area: " + area);
+        } catch (IOException e) {
+            System.err.println("Error writing to file: " + e.getMessage());
+        }
+    }
+}
diff --git a/Assignment-3/SRP/problem-2/Main.java b/Assignment-3/SRP/problem-2/Main.java
new file mode 100644
index 0000000..70076ee
--- /dev/null
+++ b/Assignment-3/SRP/problem-2/Main.java
@@ -0,0 +1,11 @@
+public class Main {
+    public static void main(String[] args) {
+        Rectangle rectangle = new Rectangle(5.0, 3.0);
+        double area = rectangle.calculateArea();
+
+        AreaFileWriter fileWriter = new AreaFileWriter();
+        fileWriter.writeAreaToFile(area);
+
+        System.out.println("Calculated Area: " + area);
+    }
+}
diff --git a/Assignment-3/SRP/problem-2/Rectangle.java b/Assignment-3/SRP/problem-2/Rectangle.java
new file mode 100644
index 0000000..452006e
--- /dev/null
+++ b/Assignment-3/SRP/problem-2/Rectangle.java
@@ -0,0 +1,13 @@
+public class Rectangle {
+    private double length;
+    private double width;
+
+    public Rectangle(double length, double width) {
+        this.length = length;
+        this.width = width;
+    }
+
+    public double calculateArea() {
+        return length * width;
+    }
+}