Construct Binary Tree from Preorder and Inorder Traversal
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
3
/ \
9 20
/ \
15 7Input
preorder = [3,9,20,15,7], inorder = [9,3,15,20,7]Output
[3,9,20,null,null,15,7]The given preorder and inorder traversals uniquely reconstruct the binary tree [3,9,20,null,null,15,7].
Example 2
-1
Input
preorder = [-1], inorder = [-1]Output
[-1]A single-node traversal reconstructs the single-node tree [-1].
Constraints
- 1 <= preorder.length <= 3000
- inorder.length == preorder.length
- -3000 <= preorder[i], inorder[i] <= 3000
- preorder and inorder consist of unique values.
- Each value of inorder also appears in preorder.
- preorder is guaranteed to be the preorder traversal of the tree.
- inorder is guaranteed to be the inorder traversal of the tree.