Convert Binary Tree to Mirror Tree Problem Statement

Given a binary tree, convert this binary tree into its mirror tree. A binary tree is a tree in which each parent node has at most two children. The mirror of a binary tree T is another binary tree M(T) where the left and right children of all non-leaf nodes are interchanged.

Input:

The first line of input contains an integer ‘T’ denoting the number of test cases. The elements of the tree are given in level order form separated by a single space. If any node does not have a left or right child, use -1 in its place. 

Output:

For every test case, the inorder traversal of the mirror tree will be printed on a separate line with the elements of the mirror tree in level order form separated by a single space, using -1 in place of NULL left or right child.

Example:

Input:

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

Explanation:

Level order input represents a tree like below:

       1
     /   \
    2     3
   /     / \
  4     5   6
   \
    7

The mirror tree would be:

       1
     /   \
    3     2
   / \     \
  6   5     4
               \
                7

Constraints:

• 1 ≤ T ≤ 100
• 1 ≤ N ≤ 3000
• -10^9 ≤ DATA ≤ 10^9

where ‘N’ is the number of nodes in the tree, and 'DATA' denotes data contained in the node of a binary tree.

Note: You don't need to print anything; just implement the function to convert the given binary tree to its mirror tree in place.