Package g0201_0300.s0230_kth_smallest_element_in_a_bst

Class Solution

java.lang.Object
g0201_0300.s0230_kth_smallest_element_in_a_bst.Solution
public class Solution extends java.lang.Object
230 - Kth Smallest Element in a BST.

Medium

Given the root of a binary search tree, and an integer k, return the kth smallest value ( 1-indexed ) of all the values of the nodes in the tree.

Example 1:

Input: root = [3,1,4,null,2], k = 1

Output: 1

Example 2:

Input: root = [5,3,6,2,4,null,null,1], k = 3

Output: 3

Constraints:

  • The number of nodes in the tree is n.
  • 1 <= k <= n <= 104
  • 0 <= Node.val <= 104

Follow up: If the BST is modified often (i.e., we can do insert and delete operations) and you need to find the kth smallest frequently, how would you optimize?

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    kthSmallest(TreeNode root, int k)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • kthSmallest

      public int kthSmallest(TreeNode root, int k)