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* docs: add Japanese documents (`ja/docs`) * docs: add Japanese documents (`ja/codes`) * docs: add Japanese documents * Remove pythontutor blocks in ja/ * Add an empty at the end of each markdown file. * Add the missing figures (use the English version temporarily). * Add index.md for Japanese version. * Add index.html for Japanese version. * Add missing index.assets * Fix backtracking_algorithm.md for Japanese version. * Add avatar_eltociear.jpg. Fix image links on the Japanese landing page. * Add the Japanese banner. --------- Co-authored-by: krahets <krahets@163.com>
69 lines
2.2 KiB
Python
69 lines
2.2 KiB
Python
"""
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File: tree_node.py
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Created Time: 2021-12-11
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Author: krahets (krahets@163.com)
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"""
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from collections import deque
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class TreeNode:
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"""二分木のノードクラス"""
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def __init__(self, val: int = 0):
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self.val: int = val # ノードの値
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self.height: int = 0 # ノードの高さ
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self.left: TreeNode | None = None # 左の子ノードへの参照
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self.right: TreeNode | None = None # 右の子ノードへの参照
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# シリアライゼーションのエンコーディングルールについては、以下を参照:
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# https://www.hello-algo.com/chapter_tree/array_representation_of_tree/
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# 二分木の配列表現:
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# [1, 2, 3, 4, None, 6, 7, 8, 9, None, None, 12, None, None, 15]
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# 二分木の連結リスト表現:
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# /——— 15
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# /——— 7
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# /——— 3
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# | \——— 6
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# | \——— 12
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# ——— 1
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# \——— 2
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# | /——— 9
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# \——— 4
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# \——— 8
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def list_to_tree_dfs(arr: list[int], i: int) -> TreeNode | None:
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"""リストを二分木にデシリアライズ: 再帰的"""
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# インデックスが配列の境界外、または対応する要素がNoneの場合、Noneを返す
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if i < 0 or i >= len(arr) or arr[i] is None:
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return None
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# 現在のノードを構築
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root = TreeNode(arr[i])
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# 左右の部分木を再帰的に構築
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root.left = list_to_tree_dfs(arr, 2 * i + 1)
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root.right = list_to_tree_dfs(arr, 2 * i + 2)
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return root
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def list_to_tree(arr: list[int]) -> TreeNode | None:
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"""リストを二分木にデシリアライズ"""
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return list_to_tree_dfs(arr, 0)
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def tree_to_list_dfs(root: TreeNode, i: int, res: list[int]) -> list[int]:
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"""二分木をリストにシリアライズ: 再帰的"""
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if root is None:
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return
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if i >= len(res):
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res += [None] * (i - len(res) + 1)
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res[i] = root.val
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tree_to_list_dfs(root.left, 2 * i + 1, res)
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tree_to_list_dfs(root.right, 2 * i + 2, res)
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def tree_to_list(root: TreeNode | None) -> list[int]:
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"""二分木をリストにシリアライズ"""
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res = []
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tree_to_list_dfs(root, 0, res)
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return res |