- Because it’s a binary search tree, we can decide whethere go
val. It’ll save lots of time instead of traversing all the nodes.
- Use a
flagto tell recursion that we’ve found a result so no more recursion.
You are given the root of a binary search tree (BST) and an integer val.
Find the node in the BST that the node’s value equals val and return the subtree rooted with that node. If such a node does not exist, return null.
Input: root = [4,2,7,1,3], val = 2