Description
Given an array of integers preorder representing the preorder traversal of a BST, construct the tree and return its root.
Examples
Input:
preorder = [8,5,1,7,10,12]Output:
[8,5,10,1,7,null,12]Explanation:
Root 8, insert 5 (left), 1 (left of 5), 7 (right of 5), 10 (right of 8), 12 (right of 10).
Input:
preorder = [4,2,1,3,6,5,7]Output:
[4,2,6,1,3,5,7]Explanation:
Inserting the preorder values into a BST yields [4,2,6,1,3,5,7].
Input:
preorder = [10,5,3,8,15]Output:
[10,5,15,3,8]Explanation:
The preorder values form the BST [10,5,15,3,8].
Constraints
- •
1 ≤ preorder.length ≤ 100