Given a binary tree, Your task is to complete the function **largestBst** that returns the size of the largest subtree which is also a Binary Search Tree (BST). If the complete Binary Tree is BST, then return the size of whole tree.

**Input:**

The task is to complete the method which takes one argument, root of Binary Tree. The Node has a data part which stores the data, pointer to left child and pointer to right child.

There are multiple test cases. For each test case, this method will be called individually.

**Output:**

The function should return the size of the max subtree which is also the BST.

**Constraints:**

1 <=T<= 30

1 <=Number of nodes<= 100

1 <=Data of a node<= 1000

**Example(To be used only for expected output):
Input**

2

2

3 2 L 3 4 R

4

10 20 L 10 30 R 20 40 L 20 60 R

3

1

There are two test cases. First case represents a tree with 3 nodes and 2 edges where root is 3, left child of 3 is 2 and right child of 3 is 4. Second test case represents a tree with 4 edges and 5 nodes.

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