Main.java

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scr = new Scanner(System.in);
        Calculator calculator = new Calculator();

        System.out.println("Enter first input: ");
        int a = scr.nextInt();

        System.out.println("Enter second input: ");
        int b = scr.nextInt();

        System.out.println(" Choose your options: \n" +
                                   "1 for addition\n" +
                                   "2 for subtraction\n" +
                                   "3 for multiplication\n" +
                                   "4 for division\n" +
                                   "");

        int option = scr.nextInt();

        if (option == 1) {
            int result = calculator.add(a, b);
            System.out.println("Result: " + result);
        }

        if (option == 2) {

        }
    }
}

import java.util.Scanner;

public class Main {

public static void main(String[] args) {
    Scanner scr = new Scanner(System.in);
    Calculator calculator = new Calculator();

    System.out.println("Enter first input: ");
    int a = scr.nextInt();

    System.out.println("Enter second input: ");
    int b = scr.nextInt();

    System.out.println(" Choose your options: \n" +
                               "1 for addition\n" +
                               "2 for subtraction\n" +
                               "3 for multiplication\n" +
                               "4 for division\n" +
                               "");

    int option = scr.nextInt();

    if (option == 1) {
        int result = calculator.add(a, b);
        System.out.println("Result: " + result);
    }

    if (option == 2) {
    	double result = calculator.subtract(a, b);
    	System.out.println("Result: " + result);

    }
    
    if (option == 3) {
		double result = calculator.multiply(a, b);
		System.out.println("Result: " + result);
	}
    
    if (option == 4) {
    	double result = calculator.div(a, b); 
    	System.out.println("Result: " + result);
    }
}

}