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91 lines
1.9 KiB
Python
91 lines
1.9 KiB
Python
"""
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File: space_complexity.py
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Created Time: 2022-11-25
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Author: krahets (krahets@163.com)
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"""
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import sys
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from pathlib import Path
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sys.path.append(str(Path(__file__).parent.parent))
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from modules import ListNode, TreeNode, print_tree
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def function() -> int:
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"""関数"""
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# 何らかの処理を行う
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return 0
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def constant(n: int):
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"""定数階"""
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# 定数、変数、オブジェクトは O(1) の空間を占める
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a = 0
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nums = [0] * 10000
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node = ListNode(0)
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# ループ内の変数は O(1) の空間を占める
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for _ in range(n):
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c = 0
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# ループ内の関数は O(1) の空間を占める
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for _ in range(n):
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function()
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def linear(n: int):
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"""線形階"""
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# 長さ n のリストは O(n) の空間を使用
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nums = [0] * n
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# 長さ n のハッシュテーブルは O(n) の空間を使用
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hmap = dict[int, str]()
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for i in range(n):
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hmap[i] = str(i)
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def linear_recur(n: int):
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"""線形時間（再帰実装）"""
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print("再帰 n =", n)
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if n == 1:
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return
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linear_recur(n - 1)
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def quadratic(n: int):
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"""二乗階"""
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# 二次元リストは O(n^2) の空間を使用
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num_matrix = [[0] * n for _ in range(n)]
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def quadratic_recur(n: int) -> int:
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"""二次時間（再帰実装）"""
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if n <= 0:
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return 0
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# 配列 nums の長さは n, n-1, ..., 2, 1
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nums = [0] * n
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return quadratic_recur(n - 1)
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def build_tree(n: int) -> TreeNode | None:
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"""指数時間（完全二分木の構築）"""
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if n == 0:
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return None
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root = TreeNode(0)
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root.left = build_tree(n - 1)
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root.right = build_tree(n - 1)
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return root
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"""Driver Code"""
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if __name__ == "__main__":
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n = 5
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# 定数階
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constant(n)
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# 線形階
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linear(n)
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linear_recur(n)
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# 二乗階
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quadratic(n)
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quadratic_recur(n)
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# 指数オーダー
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root = build_tree(n)
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print_tree(root)
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