Mirror Binary Tree

Mirror the given binary tree. That is, right child of every nodes should become left and left should become right.

Note : You don't need to print or return the tree, just mirror it.

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 : Elements in level order form (Every level in new line)

Sample Input 1:

1 2 3 4 5 6 7 -1 -1 -1 -1 -1 -1 -1 -1

Sample Output 1:

1 
3 2 
7 6 5 4

Sample Input 2:

5 10 6 2 3 -1 -1 -1 -1 -1 9 -1 -1

Sample Output 2:

5 
6 10 
3 2 
9