Given two integer arrays preorder and inorder representing the preorder and inorder traversals of a binary tree, construct and return the tree.
Example: For preorder [3,9,20,15,7] and inorder [9,3,15,20,7], build the tree with root .
Given two integer arrays preorder and inorder representing the preorder and inorder traversals of a binary tree, construct and return the tree.
Example: For preorder [3,9,20,15,7] and inorder [9,3,15,20,7], build the tree with root .