#105
Construct Binary Tree from Preorder and Inorder Traversal
medium · failed · 68.4% accepted · 16,562 likes · top 75%
array · hash table · divide and conquer · tree · binary tree
Description
Given two integer arrays preorder and inorder where preorder is the preorder traversal of a binary tree and inorder is the inorder traversal of the same tree, construct and return the binary tree.
Example 1:
Input: preorder = [3,9,20,15,7], inorder = [9,3,15,20,7]
Output: [3,9,20,null,null,15,7]
Example 2:
Input: preorder = [-1], inorder = [-1]
Output: [-1]
Solution