Construct Full Binary Tree using its Preorder traversal and Preorder traversal of its mirror tree

Given two arrays that represent Preorder traversals of a full binary tree and its mirror tree, we need to write a program to construct the binary tree using these two Preorder traversals.

A Full Binary Tree is a binary tree where every node has either 0 or 2 children.

Note: It is not possible to construct a general binary tree using these two traversal. But we can create a full binary tree using the above traversals without any ambiguity. For more details refer to this article.


Input :  preOrder[] = {1,2,4,5,3,6,7}
         preOrderMirror[] = {1,3,7,6,2,5,4}

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

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