leetcode

Serialize and Deserialize Binary Tree

Serialize and Deserialize Binary Tree

Recursive Preorder Version - 120ms

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# 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):
        """Encodes a tree to a single string.
        
        :type root: TreeNode
        :rtype: str
        """
        vals = []
        def convert(node):
            if node:
                vals.append(str(node.val))
                convert(node.left)
                convert(node.right)
            else:
                vals.append('#')
        convert(root)
        return ' '.join(vals)
    def deserialize(self, data):
        """Decodes your encoded data to tree.
        
        :type data: str
        :rtype: TreeNode
        """
        def convert():
            val = next(vals)
            if val == '#':
                return None
            node = TreeNode(int(val))
            node.left = convert()
            node.right = convert()
            return node
        vals = iter(data.split())
        return convert()        
        
# Your Codec object will be instantiated and called as such:
# codec = Codec()
# codec.deserialize(codec.serialize(root))

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