Python solution
Intuition\n Describe your first thoughts on how to solve this problem. \nThe problem is asking to implement a serialization and deserialization method for a bin
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\nThe problem is asking to implement a serialization and deserialization method for a binary tree. The serialization method should take a binary tree and convert it into a string format, while the deserialization method should take the string format and convert it back into a binary tree.\n\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\nThe serialization method can be done by doing a breadth-first traversal of the tree and appending the values of the nodes to a list. If a node is None, append "null" to the list. After the traversal, join the list into a string using "," as the delimiter.\n\nThe deserialization method can be done by splitting the string into a list using "," as the delimiter. Create the root node using the first element in the list and append it to a queue. Then, for each element in the list, starting from the second element, check if the element is "null" or not. If it is not "null", create a new node with that value and append it to the left or right of the current node in the queue, depending on whether it is the left or right child. Append the new node to the queue as well. Repeat this process until all elements in the list have been processed.\n\n\n# Complexity\n- Time complexity: O(n)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: O(n)\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\n# Definition for a binary tree node.\n# class TreeNode:\n#     def __init__(self, x):\n#         self.val = x\n#         self.left = None\n#         self.right = None\n\nclass Codec:\n\n    def serialize(self, root: Optional[TreeNode]) -> str:\n        """Encodes a tree to a single string.\n        """\n        if not root:\n            return ""\n        queue = [root]\n        output = []\n        while queue:\n            current = queue.pop(0)\n            if current:\n                output.append(str(current.val))\n                queue.append(current.left)\n                queue.append(current.right)\n            else:\n                output.append("null")\n        return ",".join(output)\n        \n\n    def deserialize(self, data: str) -> Optional[TreeNode]:\n        """Decodes your encoded data to tree.\n        """\n        if not data:\n            return None\n        data = data.split(",")\n        root = TreeNode(int(data[0]))\n        queue = [root]\n        i = 1\n        while queue:\n            current = queue.pop(0)\n            if data[i] != "null":\n                current.left = TreeNode(int(data[i]))\n                queue.append(current.left)\n            i += 1\n            if data[i] != "null":\n                current.right = TreeNode(int(data[i]))\n                queue.append(current.right)\n            i += 1\n        return root\n\n# Your Codec object will be instantiated and called as such:\n# Your Codec object will be instantiated and called as such:\n# ser = Codec()\n# deser = Codec()\n# tree = ser.serialize(root)\n# ans = deser.deserialize(tree)\n# return ans\n```
['Python3']