Kth Smallest Element in a BST
Given a binary search tree, write a function kthSmallest to find the kth smallest element in it. Note: You may assume k is always valid, 1 ≤ k ≤ BST’s total elements. Example 1: 1 2 3 4 5 6 7 Input: root = [3,1,4,null,2], k = 1 3 / \ 1 4 \ 2 Output: 1 Example 2: ...