Journal Archive

2022

/**
 * 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;
    let mid = Math.floor(nums.length / 2);
    
    const root = new TreeNode(nums[mid]);
    root.left = sortedArrayToBST(nums.slice(0,mid));
    root.right = sortedArrayToBST(nums.slice(mid + 1));
    return root;
};

Day 26: Solving one of LeetCode problems

108. Convert Sorted Array to Binary Search Tree Difficulty - Easy

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,null,3] and [3,1] are both height-balanced BSTs.