import java.util.Scanner;
 
public class MenuDrivenCalculator {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
 
        System.out.println("====== BASIC CALCULATOR ======");
        System.out.println("1. Addition");
        System.out.println("2. Subtraction");
        System.out.println("3. Multiplication");
        System.out.println("4. Division");
        System.out.println("5. Modulus");
        System.out.print("Enter your choice (1-5): ");
       
        int choice = sc.nextInt();
 
        System.out.print("Enter first number: ");
        double num1 = sc.nextDouble();
 
        System.out.print("Enter second number: ");
        double num2 = sc.nextDouble();
 
        double result;
 
        switch (choice) {
            case 1:
                result = num1 + num2;
                System.out.println("Result = " + result);
                break;
 
            case 2:
                result = num1 - num2;
                System.out.println("Result = " + result);
                break;
 
            case 3:
                result = num1 * num2;
                System.out.println("Result = " + result);
                break;
 
            case 4:
                if (num2 == 0) {
                    System.out.println("Error! Division by zero is not allowed.");
                } else {
                    result = num1 / num2;
                    System.out.println("Result = " + result);
                }
                break;
 
            case 5:
                result = num1 % num2;
                System.out.println("Result = " + result);
                break;
 
            default:
                System.out.println("Invalid choice! Please choose between 1–5.");
        }
 
        sc.close();
    }
}