K-th Largest Number in a BST

Given a binary search tree (BST) consisting of integers and containing 'N' nodes, your task is to find and return the K-th largest element in this BST.

If there is no K-th largest element in the BST, return -1.

Example:

Input:

1
K: 3
BST elements (level-order): 1 2 3 4 -1 5 6 -1 7 -1 -1 -1 -1 -1 -1

Output:

5

Explanation:

For the binary search tree created from the input, the in-order traversal gives the sequence [1, 2, 3, 4, 5, 6, 7]. The 3rd largest element is 5.

Constraints:

• 1 <= T <= 100
• 1 <= N <= 5000
• 1 <= K <= 5000
• 0 <= Data <= 10^6 and Data ≠ -1
• Time Limit: 1 second

Note:

You do not have to print anything; only implement the function to return the desired result.