Meta / Amazon / Google / Microsoft| Trim a Binary Search Tree | LeetCode-669: Medium | JavaScript Implementation

We will be seeing the solution to the LeetCode problem 669 in JavaScript. I hope you will find it useful.

Problem Statement:
Given the root of a binary search tree and the lowest and highest boundaries as low and high, trim the tree so that all its elements lies in [low, high]. Trimming the tree should not change the relative structure of the elements that will remain in the tree (i.e., any node's descendant should remain a descendant). It can be proven that there is a unique answer.

Return the root of the trimmed binary search tree. Note that the root may change depending on the given bounds

Link to Problem: https://leetcode.com/problems/trim-a-binary-search-tree/

JavaScript Implementation:

var trimBST = function(root, low, high) {
    const util = (node)=>{
        if(!node) return null;
        
        node.left = util(node.left)
        node.right = util(node.right)
        
        if(node.val < low) return node.right
        if(node.val > high) return node.left
        return node
        
    }
    root = util(root)      
    return root
};

Thank you for reading hope this code is helpful to you.