Flattening the tree
<p>Flattening the data: How to write a recursive function that returns a linked list of nodes, when given a binary tree of nodes? (The tree can be modified)</p>

<p>In this questioning what does the flattening the tree mean? Is it we need to maintain all the elements of a binary tree in a list with its left and right pointers or there is another catch which i am not getting?</p>

<p>Secondly (the tree can be modified) does they mean the fun should be able to handle any modification of tree along with build?</p>
