Операции между числа

import java.util.Scanner;

public class demo {
    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        double firstNum = Double.parseDouble(scanner.nextLine());
        double secondNum =Double.parseDouble(scanner.nextLine());
        String operator = scanner.nextLine();

        double result = 0.0;

        if (operator.equals("+")) {
            result = firstNum + secondNum;
        } else if (operator.equals("-")) {
            result = firstNum - secondNum;
        } else if (operator.equals("*")) {
            result = firstNum * secondNum;
        } else if (operator.equals("/")) {

            if (secondNum == 0) {
                System.out.printf("Cannot divide %.0f by zero", firstNum);
                return;
            } else {
                result = firstNum / secondNum;
                System.out.printf("%.0f %s %.0f = %.2f", firstNum, operator, secondNum, result);
                return;
            }
        } else if (operator.equals("%")) {

            if (secondNum == 0) {
                System.out.printf("Cannot divide %.0f by zero", firstNum);
                return;
            } else {
                result = firstNum % secondNum;
                System.out.printf("%.0f %s %.0f = %.0f", firstNum, operator, secondNum, result);
                return;
            }
        }

        if(result % 2 == 0){
            System.out.printf("%.0f %s %.0f = %.0f - even", firstNum, operator, secondNum, result);
        }else{
            System.out.printf("%.0f %s %.0f = %.0f - odd", firstNum, operator, secondNum, result);
        }
    }
}