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Convert Sorted Array to Binary Search Tree

Problem statement​

Given an integer array nums where the elements are sorted in ascending order, convert it to a height-balanced binary search tree.

A height-balanced binary tree is a binary tree in which the depth of the two subtrees of every node never differs by more than one.

Example 1:

Input: nums = [-10,-3,0,5,9]Output: [0,-3,9,-10,null,5]Explanation: [0,-10,5,null,-3,null,9] is also accepted:

Example 2:

Input: nums = [1,3]Output: [3,1]Explanation: [1,3] and [3,1] are both a height-balanced BSTs.

Constraints:

  • 1 <= nums.length <= 104
  • -104 <= nums[i] <= 104
  • nums is sorted in a strictly increasing order.

My solution​

/**
 * Definition for a binary tree node.
 * function TreeNode(val, left, right) {
 *     this.val = (val===undefined ? 0 : val)
 *     this.left = (left===undefined ? null : left)
 *     this.right = (right===undefined ? null : right)
 * }
 */
/**
 * @param {number[]} nums
 * @return {TreeNode}
 */
var sortedArrayToBST = function(nums) {
    if (nums.length === 0) {
        return null
    }
    const mid = Math.floor(nums.length / 2)
    return new TreeNode(
        nums[mid],
        sortedArrayToBST(nums.slice(0, mid)),
        sortedArrayToBST(nums.slice(mid + 1))
    )
};