Given a Binary search tree. Your task is to complete the function which will return the Kth largest element without doing any modification in Binary Search Tree.
k = 2
K = 1
You don't need to read input or print anything. Your task is to complete the function kthLargest() which takes the root of the BST and an integer K as inputs and returns the Kth largest element in the given BST.
Expected Time Complexity: O(H + K).
Expected Auxiliary Space: O(H)
1 <= N <= 1000
1 <= K <= N