Java Program to make a calculator using switch cases

import java.util.Scanner;
public class demo1 
{
 public static void main(String[] args) 
 {
  double num1, num2;
  Scanner input = new Scanner(System.in);
  System.out.print("Enter first number:");

  num1 = input.nextDouble();
  System.out.print("Enter second number:");
  num2 = input.nextDouble();

  System.out.print("Enter an operator (+, -, *, /): ");
  char operator = input.next().charAt(0);
  input.close();
  double output;

  switch(operator)
  {
   case '+':
   output = num1 + num2;
   break;

   case '-':
   output = num1 - num2;
   break;

   case '*':
   output = num1 * num2;
   break;

   case '/':
   output = num1 / num2;
   break;           
   default:
   System.out.printf("You have entered wrong operator");
   return;
   }

   System.out.println(num1+" "+operator+" "+num2+": "+output);
 }
}