If inorder and postorder was given then how to solve?

#1

If inorder and postorder array were given then how to solve? What will be the approach then ?

#2

The idea is to start with the root node which would be the last item in the postorder sequence and find boundary of its left and right subtree in the inorder sequence. To find the boundary, we search for index of the root node in inorder sequence. Now all keys before the root node in inorder sequence becomes part of the left subtree and all keys after the root node becomes part of the right subtree. We repeat this recursively for all nodes in the tree, and construct the tree in the process