minimum-absolute-difference-in-bst.md

<p>Given a binary search tree with non-negative values, find the minimum <a href="https://en.wikipedia.org/wiki/Absolute_difference">absolute difference</a> between values of any two nodes.</p>

<p><b>Example:</b></p>

<pre>
<b>Input:</b>

   1
    \
     3
    /
   2

<b>Output:</b>
1

<b>Explanation:</b>
The minimum absolute difference is 1, which is the difference between 2 and 1 (or between 2 and 3).
</pre>

<p>&nbsp;</p>

<p><b>Note:</b> There are at least two nodes in this BST.</p>