title: How to sort binary array by amount of ones in their binary representation
body: <p>Numbers with identical amount of "1"s should be ordered by decimal representation. </p>
  
  <p>For example:</p>
  
  <pre><code>srt([3,7,8,9]) =&gt; [8,3,9,7]  # 1000, 11, 1001, 111
  </code></pre>