Given a Binary Search Tree (BST) and a range [min, max], remove all keys which are outside the given range. The modified tree should also be BST.
Example 1:
Input:
Range = [-10, 13]
Output:
-8 6 7 13
Explanation:
Nodes with values -13, 14 and 15 are
outside the given range and hence are
removed from the BST.
This is the resultant BST and it's
inorder traversal is -8 6 7 13.
Example 2:
Input:
Range = [2, 6]
14
/ \
4 16
/ \ /
2 8 15
/ \ / \
-8 3 7 10
Output:
2 3 4
Explanation:
After removing nodes outside the range,
the resultant BST looks like:
4
/
2
\
3
The inorder traversal of this tree is: 2 3 4
Your task:
You don't have to read input or print anything. Your task is to complete the function removekeys() which takes the root node of the BST and the range as input and returns the root of the modified BST after removing the nodes outside the given range.

Expected Time Complexity: O(number of nodes)
Expected Auxiliary Space: O(h)

Constraints:
1 ≤ Number of Nodes ≤ 10^{5}
1 ≤ K ≤ 10^{5}

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