[Python手撕]二叉树的序列化和反序列化

# Definition for a binary tree node.
# class TreeNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

class Codec:
    def serialize(self, root):

        def dfs(root):
            if root:
                left = dfs(root.left)
                right = dfs(root.right)
                return str(root.val) +","+ left +","+ right
            else:
                return "None"
        return dfs(root)



    def deserialize(self, data):
        nums = iter(data.split(","))
        def dfs(nums):
            val = next(nums)
            if val == "None":
                return None
            else:
                root = TreeNode(val)
                root.left = dfs(nums)
                root.right = dfs(nums)
                return root
        
        root = dfs(nums)

        return root
        

# Your Codec object will be instantiated and called as such:
# ser = Codec()
# deser = Codec()
# ans = deser.deserialize(ser.serialize(root))