title: How do I iterate over Binary Tree?
body: <p>Right now I have</p>
  
  <pre><code> private static void iterateall(BinaryTree foo) {
      if(foo!= null){
      System.out.println(foo.node);
      iterateall(foo.left);
      iterateall(foo.right);
     }
    }
  </code></pre>
  
  <p>Can you change it to Iteration instead of a recursion?</p>