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Ikko Eltociear Ashimine
954c45864b
* 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>
37 lines
1.1 KiB
Python
37 lines
1.1 KiB
Python
"""
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File: climbing_stairs_backtrack.py
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Created Time: 2023-06-30
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Author: krahets (krahets@163.com)
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"""
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def backtrack(choices: list[int], state: int, n: int, res: list[int]) -> int:
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"""バックトラッキング"""
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# n 段目に登ったとき、解の数に 1 を加える
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if state == n:
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res[0] += 1
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# すべての選択肢を走査
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for choice in choices:
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# 枝刈り：n 段を超えて登ることを許可しない
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if state + choice > n:
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continue
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# 試行：選択を行い、状態を更新
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backtrack(choices, state + choice, n, res)
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# 撤回
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def climbing_stairs_backtrack(n: int) -> int:
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"""階段登り：バックトラッキング"""
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choices = [1, 2] # 1 段または 2 段登ることを選択可能
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state = 0 # 0 段目から登り始める
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res = [0] # res[0] を使用して解の数を記録
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backtrack(choices, state, n, res)
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return res[0]
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"""ドライバーコード"""
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if __name__ == "__main__":
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n = 9
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res = climbing_stairs_backtrack(n)
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print(f"{n} 段登り、合計 {res} 通りの解がある") |