Reconstruct tree from inorder and postorder

Given two arrays representing the inorder and postorder traversals of a binary tree with unique values, reconstruct the original binary tree and return its root node. Implement a recursive solution, clearly defining base cases such as empty ranges. Analyze the time and space complexity. If you choose array slicing, explain its impact on complexity; alternatively, implement an index-range approach using a value-to-index map to achieve linear time.