https://leetcode.com/problems/convert-sorted-list-to-binary-search-tree/
Given the head of a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.
For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two subtrees of every node never differ by more than 1.
Example 1:
Input: head = [-10,-3,0,5,9] Output: [0,-3,9,-10,null,5] Explanation: One possible answer is [0,-3,9,-10,null,5], which represents the shown height balanced BST. Example 2:
Input: head = [] Output: [] Example 3:
Input: head = [0] Output: [0] Example 4:
Input: head = [1,3] Output: [3,1]
Constraints:
The number of nodes in head is in the range [0, 2 * 104]. -10^5 <= Node.val <= 10^5