(Dalisay)App.java

public class App {

    public static void main(String[] args) {
        System.out.println("Hello World!");

        myVariables();
        DataTypes();
        Casting();
        Operations();
    }

    public static void myVariables() {
        int Book = 10;
        double Pen = 20.5;
        String Paper = "Hello";
        char Pencil = 'P';
        boolean Binder = true;
        
        System.out.println("My Variable:");
        System.out.println("int: " + Book);
        System.out.println("double: " + Pen);
        System.out.println("String: " + Paper);
        System.out.println("char: " + Pencil);
        System.out.println("boolean: " + Binder);
    }

    public static void DataTypes() {
        byte Watch = 9;
        short Fan = 50;
        int Shirt = 100;
        long Gown = 857;
        float Bag = 10.5f;
        double Pants = 50.99;
        char Umbrella = 'A';
        boolean Shoes = true;

        System.out.println("\nDifferent Data Types:");
        System.out.println("byte: " + Watch);
        System.out.println("short: " + Fan);
        System.out.println("int: " + Shirt);
        System.out.println("long: " + Gown);
        System.out.println("float: " + Bag);
        System.out.println("double: " + Pants);
        System.out.println("char: " + Umbrella);
        System.out.println("boolean: " + Shoes);
    }

    public static void Casting() {
        int intVar = 20;
        double WideCast = intVar;
        
        double doubleVar = 20.78;
        int NarCast = (int) doubleVar;

        System.out.println("\nCasting:");
        System.out.println("Wide casting (int to double): " + WideCast);
        System.out.println("Narrow casting (double to int): " + NarCast);
    }

    public static void Operations() {
        int a = 20;
        int b = 21;

        System.out.println("\nOperations on different operators:");
        System.out.println("Addition (a + b): " + (a + b));
        System.out.println("Subtraction (a - b): " + (a - b));
        System.out.println("Multiplication (a * b): " + (a * b));
        System.out.println("Division (a / b): " + (a / b));
        System.out.println("Modulus (a % b): " + (a % b));

        System.out.println("a is greater than b: " + (a > b));

        boolean result = (a > b) && (a != b);
        System.out.println("Logical AND operation (a > b && a != b): " + result);
    }
}