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* Retranslate the complete Japanese online edition from Chinese * Fit Japanese homepage labels and localize heading permalinks * Point Japanese contribution instructions to the Japanese preview * Replace locale conditionals with multilingual UI tables
40 lines
1.1 KiB
Python
40 lines
1.1 KiB
Python
"""
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File: top_k.py
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Created Time: 2023-06-10
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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 print_heap
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import heapq
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def top_k_heap(nums: list[int], k: int) -> list[int]:
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"""ヒープを使って配列内の大きいほうから k 個の要素を求める"""
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# 最小ヒープを初期化する
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heap = []
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# 配列の先頭 k 個の要素をヒープに挿入する
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for i in range(k):
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heapq.heappush(heap, nums[i])
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# k+1 番目の要素から始め、ヒープの長さを k に保つ
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for i in range(k, len(nums)):
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# 現在の要素がヒープの先頭要素より大きい場合、先頭要素を取り出し、現在の要素を挿入する
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if nums[i] > heap[0]:
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heapq.heappop(heap)
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heapq.heappush(heap, nums[i])
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return heap
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"""実行用コード"""
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if __name__ == "__main__":
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nums = [1, 7, 6, 3, 2]
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k = 3
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res = top_k_heap(nums, k)
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print(f"大きいほうから {k} 個の要素は")
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print_heap(res)
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