Serialize and Deserialize Binary Tree

Design an algorithm to serialize a binary tree to a string and deserialize it back.

Input: level-order array (comma-separated, 'null' for missing). Output: serialized then deserialized back to level-order.

Input:

1,2,3,null,null,4,5

Output:

1 2 3 null null 4 5

Reasoning:

The input string 1,2,3,null,null,4,5 is first split into an array of node values, representing a level-order traversal of the binary tree.
A binary tree is constructed from this array, where null values indicate missing nodes:
- Root node: 1
- Left child of 1: 2
- Right child of 1: 3
- Left child of 2: null
- Right child of 2: null
- Left child of 3: 4
- Right child of 3: 5
The tree is then serialized to a string, which in this case is the same as the input string since the serialization is based on level-order traversal.
The serialized string is then deserialized back to a binary tree, resulting in the same tree structure as before.
The final output is obtained by performing a level-order traversal of the deserialized tree, resulting in 1 2 3 null null 4 5.