Construct Binary Tree from Inorder and Postorder Traversal

Given two lists representing the inorder and postorder traversal of a binary tree of integer type with 'N' nodes, construct the binary tree and return its root.

The binary tree contains only unique elements.

Input:

First line contains integer 'T', number of test cases.
For each test case:
- First line contains integer 'N', number of nodes.
- Second line contains 'N' space-separated integers, representing the Postorder traversal.
- Third line contains 'N' space-separated integers, representing the Inorder traversal.

Output:

For each test case, print the level order traversal of the constructed binary tree on a new line.

Example:

IN_ORDER = [9, 3, 15, 20, 7] 
POST_ORDER = [9, 15, 7, 20, 3] 
The resulting binary tree from the traversals is:

Constraints:

• 1 <= T <= 10
• 1 <= N <= 10000
• 1 <= POST_ORDER[i], IN_ORDER[i] <= 100000

Note:

You do not need to print anything; focus on implementing the function.