Serialize and Deserialize Binary Tree

Problem: Serialize and Deserialize Binary Tree Design an algorithm to serialize and deserialize a binary tree. Serialization: encode a binary tree into a string. Deserialization: decode the string back into the original binary tree. You must guarantee that for any binary tree root, deserialize(serialize(root)) reconstructs a tree with exactly the same structure and values. Node Definition class TreeNode: def __init__(self, val=0, left=None, right=None): self.val = val self.left = left self.right = right Input/Output Format for Testing The test harness uses preorder serialization: A null node is represented by #. Tokens are separated by commas. Input contains one line: a preorder serialization string. Your program should deserialize it and then serialize it back. Constraints Number of nodes: 0 <= n <= 10^4 Node values are 32-bit signed integers Example Input: 1,2,#,#,3,4,#,#,5,#,# Output: 1,2,#,#,3,4,#,#,5,#,# Example Input # Output #