Implement a Binary Search Tree

Let's implement a Binary Search Tree! Recall that a binary search tree, or a BST, is a binary tree that is ordered via these two properties:

1. The left sub-tree of a node has a value less than or equal to its parent node's value.
2. The right sub-tree of a node has a value greater than to its parent node's value.

Given the following tree node definition:

class Node {
  constructor(val) {
    this.val = val;
    this.left = null;
    this.right = null;
  }
}

Can you fill out the skeleton code and implement a binary search tree with #add and #remove methods?

class BST {
  constructor(val) {
    this.root = new Node(val);
  }

  add(val) {
    // fill this in
  }

  remove(val) {
    // fill this in
  }
}

Constraints

• Maximum number of nodes <= 1000
• Value of each node can lie between -1000000000 and 1000000000
• Expected time complexity for most BST operations (including search, insert, and delete) is O(log n) where n being the number of nodes
• Expected space complexity : O(n)

```js
class BST {
	constructor(val) {
		this.root = new Node(val);
	}

	add(val) {
    // fill this in
  }

	remove(val) {
    // fill this in    
  }
}

// const bst = new BST(4);
// bst.add(3);
// bst.add(5);
// console.log(bst.root.left.val === 3);
// console.log(bst.root.right.val === 5);
```