title: Sorting a number's digits without using an array
body: <p>What I need to do for my homework is to sort the digits of a positive number from low to high.</p>
  
  <p>I can use</p>
  
  <ul>
  <li>operators</li>
  <li>integers/doubles/floats/chars</li>
  <li>if/switch and loops</li>
  </ul>
  
  <p>I cannot use</p>
  
  <ul>
  <li>char array()</li>
  <li>string</li>
  </ul>