Reverse Level Order Traversal

Level MEDIUM

Given a binary tree.Traverse the tree in the manner of reverse level order

Example:

                       5
                      / \  
                     6   2  
                        / \
                       2   3
                      / \
                     9   7

    Reverse level order traversal for this tree is:
    7 9 3 2 2 6 5

Input format :

Line 1 :  Elements in level order form (separated by space)
(If any node does not have left or right child, take -1 in its place)

Output Format :

Print Reverse level order traversal 

Constraints :

1 <= N <= 10^5

Input:

5 6 2 2 3 -1 -1 9 7 -1 -1 -1 -1

Output :

7 9 3 2 2 6 5