/**
 * Definition for a binary tree node.
 * function TreeNode(val) {
 *     this.val = val;
 *     this.left = this.right = null;
 * }
 */
/**
 * @param {TreeNode} root
 * @param {TreeNode} p
 * @param {TreeNode} q
 * @return {TreeNode}
 */
var lowestCommonAncestor = function(root, p, q) {
	let curr = root
	for (;;) {
		if (p.val === curr.val || q.val === curr.val) return curr
		if (curr.val < p.val && curr.val < q.val) curr = curr.right
		else if (p.val < curr.val && q.val < curr.val) curr = curr.left
		else return curr
	}
}