Given the root node of a binary search tree (BST) and an integer k, write a function to find and return the k-th smallest value in the BST. The smallest value in the tree is 1.
The binary tree is represented by a collection of TreeNodes, where each node has optional left and right child nodes, which are also TreeNodes.
A TreeNode has the following interface:
interface TreeNode {val: number;left: TreeNode | null;right: TreeNode | null;}
root: TreeNode: Root node of the tree. Examples display a level-order traversal of the treek: number: A positive integerInput: root = [7,3,10,1,5,8,12], k = 2Output: 3Explanation: In this BST, the second smallest value is 3.
Input: root = [1,null,2,null,3,null,4,null,5], k = 4Output: 4Explanation: In this right-skewed BST, the fourth smallest value is 4.
Input: root = [8,6,10,5,7,9,12], k = 5Output: 9Explanation: In this BST, the fifth smallest value is 9.
k <= Number of nodes <= 1000TreeNode.val <= 1,000,000Given the root node of a binary search tree (BST) and an integer k, write a function to find and return the k-th smallest value in the BST. The smallest value in the tree is 1.
The binary tree is represented by a collection of TreeNodes, where each node has optional left and right child nodes, which are also TreeNodes.
A TreeNode has the following interface:
interface TreeNode {val: number;left: TreeNode | null;right: TreeNode | null;}
root: TreeNode: Root node of the tree. Examples display a level-order traversal of the treek: number: A positive integerInput: root = [7,3,10,1,5,8,12], k = 2Output: 3Explanation: In this BST, the second smallest value is 3.
Input: root = [1,null,2,null,3,null,4,null,5], k = 4Output: 4Explanation: In this right-skewed BST, the fourth smallest value is 4.
Input: root = [8,6,10,5,7,9,12], k = 5Output: 9Explanation: In this BST, the fifth smallest value is 9.
k <= Number of nodes <= 1000TreeNode.val <= 1,000,000console.log() statements will appear here.