Find k-th smallest element in BST

PROBLEM :

Given root of binary search tree and K as input, find K-th smallest element in BST. Your task is to return the K-th smallest element in BST from the function k_smallest_element().

Note: The Time Complexity will be O(h) where h is the height of the Tree.

Input:
The first line of input will contain the number of test cases T. Then T test cases follow. First line of every test case will be n, denoting the number of nodes in the BST. Second line of every test case will be n spaced integers denoting the Integer value of Nodes in BST. Third line of every test case will be k, denoting kth the smallest number.

Output:
For each test case, output will be the kth smallest element of BST.

Constraints:
1<=T<=100
1<=N<=100
1<=K<=N

Example(To be used only for expected output):
Input:
1
5
20 8 4 22 12
3

Output:
12

--------------------------------------------------------------------------------
SIMPLE c++ IMPLEMENTATION :
--------------------------------------------------------------------------------

/*Complete the function below
Node is as follows:
struct Node
{
    int data;
    int lCount;

    Node* left;
    Node* right;
};*/

int KthSmallestElement(Node *root, int k)
{
    int ans ;
    if(root)
    {
        while(root)
        {
            if(root->lCount+1==k)
            {
                ans=root->data ;
                break ;
            }
            else if(root->lCount<k)
            {
                k=k-(root->lCount+1) ;
                root=root->right ;
            }
            else
                root=root->left ;
        }
    }
    return ans ;
}

--------------------------------------------------------------------------------

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