[LeetCode] Serialize and Deserialize BST 二叉搜尋樹的序列化和去序列化

Serialization is the process of 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 just 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.

Note: Do not use class member/global/static variables to store states. Your serialize and deserialize algorithms should be stateless.

解法一：

另一種方法是層序周遊的非遞歸解法，這種方法略微複雜一些，我們需要借助queue來做，本質是BFS算法，也不是很難了解，就是BFS算法的正常套路稍作修改即可，參見代碼如下：

解法二：