Given a Binary Search Tree, modify the given BST such that it is balanced and has minimum possible height.

Examples :

Input:
       30
      /
     20
    /
   10
Output:
     20
   /   \
 10     30

Input:
         4
        /
       3
      /
     2
    /
   1
Output:
      3            3           2
    /  \         /  \        /  \
   1    4   OR  2    4  OR  1    3   OR ..
    \          /                   \
     2        1                     4

Your Task:
The task is to complete the function buildBalancedTree() which takes root as the input argument and returns the root of tree after converting the given BST into a balanced BST with minimum possible height. The driver code will print the height of the updated tree in output itself.

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(N)
Here N denotes total number of nodes in given BST.

Constraints:
1<=N<=200