title: How can I multiply all the digits in an integer (between 000 & 1000 exclusive) without using control statements or loops?
body: <p>I'm trying to write a program that can multiply all the digits of a number from 0 to 1000 exclusive using only math expressions in Java. My program works fine as long as the user types in a 3-digit number, but results in 0 if they type in anything less than 100.</p>
  
  <p>I have tried getting the last digit of the input with '%10' and removing the last digit with '/10' but without a control statement to detect if the input has been reduced to zero, the program ends up multiplying by 0 when a 2-digit number has been reduced to zero, giving an incorrect result.   </p>
  
  <pre><code>public class MultiplyDigits {
      public static void main(String[] args){
          java.util.Scanner input = new java.util.Scanner(System.in);
          System.out.print("Enter a number between 0 and 1000: ");
          int number = input.nextInt();
          int product = 1;
          product*=number%10;
          number/=10;
          product*=number%10;
          number/=10;
          product*=number%10;
          System.out.println(product);
      }
  }
  </code></pre>
  
  <p>An input of 55 should result in 25, but my program does 5 x 5 x 0 = 0</p>
  
  <p>An input of 999 results in 729, which is correct. 9 x 9 x 9 = 729</p>
  
  <p>Some more clarification, this is a problem out of the 2nd chapter of a textbook for complete novices. The author has not covered selection statements, loops, writing our own methods or classes, or anything more advanced than elementary programming, so the implication is that this is doable without those. The book has covered invoking methods in classes built into Java, although the author has only mentioned methods in the Math and System classes. For example, Math.max(), Math.min(), Math.pow(), System.currentTimeMillis();</p>