title: Scan tree structure from bottom up?
body: <p>If given the following tree structure or one similar to it:</p>
  
  <p><img src="https://i.stack.imgur.com/HP6Ld.png" alt="enter image description here"></p>
  
  <p>I would want the string ZYXWVUT returned. I know how to do this with a binary tree but not one that can have more than child nodes. Any help would be much appreciated.</p>