Given a BST, output the k closest values in this BST to x. Sort the output by value.
The output set is guaranteed to be unique.
Do not convert the BST to a list.
Input
bst: a valid BST of size n.
x: an integer representing the number to find the k closest numbers to.
k: an integer.
Output
A list of integers containing the k closest numbers to x.
Examples
Example 1
Input
bst = <See explanation>
x = 7
k = 4
Output: [5, 6, 8, 10]
Explanation
All four numbers in the output are within 3 away from 7.
Constraints
1 <= k <= n <= 10^5