Kth Smallest Element in BST
Medium Acceptance 76.77% Points 30
You are given the root of a Binary Search Tree (BST) and an integer k. Your task is to return the kth smallest element in the BST.
Examples
Example 1
Input: root = [3,1,4,null,2], k = 1
Output: 1
Explanation: The smallest element in the BST is 1.
Example 2
Input: root = [5,3,6,2,4,null,null,1], k = 3
Output: 3
Explanation: The elements in sorted order are 1, 2, 3, 4, 5, 6, so the 3rd smallest element is 3.
Example 3
Input: root = [2,1,3], k = 2
Output: 2
Explanation: The 2nd smallest element in the BST is 2.
Constraints
- 1 = Number of nodes = 105
- -10? = Node.data = 10?
- 1 = k = Number of nodes
Topics
Companies
Added 08 Aug 2026 76.77% acceptance
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