import java.util.Scanner;

public class Calculator {

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

        System.out.print("Enter the first number: ");
        double num1 = scanner.nextDouble();

        System.out.print("Enter the operator (+, -, *, /): ");
        char operator = scanner.next().charAt(0);

        System.out.print("Enter the second number: ");
        double num2 = scanner.nextDouble();

        double result = calculate(num1, operator, num2);
        System.out.println("Result: " + result);
    }

    public static double calculate(double num1, char operator, double num2) {
        double result = 0;

        if (operator == '+') {
            result = num1 + num2;
        } else if (operator == '-') {
            result = num1 - num2;
        } else if (operator == '*') {
            result = num1 * num2;
        } else if (operator == '/') {
            result = num1 / num2;
        } else {
            System.out.println("Invalid operator, please try again.");
            Scanner scanner = new Scanner(System.in);
            operator = scanner.next().charAt(0);
            result = calculate(num1, operator, num2);
        }

        return result;
    }
}