title: Filling empty Binary tree as Binary search tree without changing structure (Node linkage)
body: <p>I had an interview today and I was asked to code this..
  You have an already created unordered Binary tree with no data in any node. 
  We have an array having equal number of elements. 
  We have to insert data in the binary tree as a binary search tree without changing the structure of binary tree. </p>
  
  <p>The method I came up with was to sort the array and then traverse its element one by one, putting each data element in the first empty inorder node in the tree. 
  But I guess that's incorrect as I wasn't selected. </p>
  
  <p>Sorry if algorithm questions aren't allowed. I'll take this down if there is an issue like this... </p>