/
449_Serialize_and_Deserialize_BST.py
43 lines (37 loc) · 1.24 KB
/
449_Serialize_and_Deserialize_BST.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
# Definition for a binary tree node.
# class TreeNode(object):
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
from collections import deque
# Approach 1: No space optimisation done. Using preorder DFS
class Codec:
def serialize(self, root):
"""Encodes a tree to a single string.
:type root: TreeNode
:rtype: str
"""
if not root:
return 'X' + ','
leftSubTree = self.serialize(root.left)
rightSubTree = self.serialize(root.right)
return str(root.val) + "," + leftSubTree + rightSubTree
def deserialize(self, data):
"""Decodes your encoded data to tree.
:type data: str
:rtype: TreeNode
"""
queue = deque(data.split(","))
return self.deserializeHelper(queue)
def deserializeHelper(self, stream):
if not stream or stream[0] == "X":
return None
node = TreeNode(stream.popleft())
node.left = self.deserializeHelper(stream)
stream.popleft()
node.right = self.deserializeHelper(stream)
return node
# Your Codec object will be instantiated and called as such:
# codec = Codec()
# codec.deserialize(codec.serialize(root))