Search in a Binary Search Tree

 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.


 


Example 1:



Input: root = [4,2,7,1,3], val = 2

Output: [2,1,3]

Example 2:



Input: root = [4,2,7,1,3], val = 5

Output: []



/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public TreeNode searchBST(TreeNode root, int val) {
        while (root != null) {
            if (root.val == val)
                return root;
            else if (val < root.val)
                root = root.left;
            else
                root = root.right;
        }
        return null;
    }
}

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