Kalkulator (+)/(-) input user

package praktikum5perfection;
import java.util.Scanner;
/**
 *
 * @author Faridl
 */
public class Remote {
    public static void main(String[] args) {
    String Num1,Num2;

    Scanner input = new Scanner(System.in);
        System.out.println("=========Operation Simple Mathematic Begin==========");
        System.out.println("1.Adding Operation");
        System.out.println("2.Minus Operation");
        System.out.println("3.Exit");
        System.out.println("=================Enter Your Choice==================");
        int Select = input.nextInt();
        switch (Select){
            case 1:
                System.out.println("Enter The First Amount:");
                Num1= input.next();
                System.out.println("Enter The Second Amount");
                Num2= input.next();
            System.out.println("The Result : " + Plus.plus(Num1, Num2));
            break;
            case 2:
                System.out.println("Enter The First Amount:");
                Num1= input.next();
                System.out.println("Enter The Second Amount");
                Num2= input.next();
                System.out.println("The Result : "+ Minus.minus(Num1, Num2));
            break;
            case 3:
                System.exit(0);
        }
    }
}