title: Random number from a range without a certain number in the middle of the range
body: <p>I'm generating a number from 0 to 11 randomly like this:</p>
  
  <pre><code>int n = arc4random() % 12;
  </code></pre>
  
  <p>But, I'd like to not get 5 or 6 as output. How can I do that?</p>