Serialization is converting a data structure or object into a sequence of bits so that it can be stored in a file or memory buffer, or transmitted across a network connection link to be reconstructed later in the same or another computer environment.

Design an algorithm to serialize and deserialize a binary search tree. There is no restriction on how your serialization/deserialization algorithm should work. You need to ensure that a binary search tree can be serialized to a string, and this string can be deserialized to the original tree structure.

The encoded string should be as compact as possible.

Example 1:

    Input: root = [2,1,3]
    Output: [2,1,3]

Example 2:

    Input: root = []
    Output: []

Constraints:

- The number of nodes in the tree is in the range `[0, 104]`.
- `0 <= Node.val <= 104`
- The input tree is guaranteed to be a binary search tree.