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* add some documentation * [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci * fix typing * Update heap_sort.py * Update heap_sort.py --------- Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com> Co-authored-by: Christian Clauss <cclauss@me.com>
68 lines
1.9 KiB
Python
68 lines
1.9 KiB
Python
"""
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A pure Python implementation of the heap sort algorithm.
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"""
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def heapify(unsorted: list[int], index: int, heap_size: int) -> None:
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"""
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:param unsorted: unsorted list containing integers numbers
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:param index: index
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:param heap_size: size of the heap
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:return: None
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>>> unsorted = [1, 4, 3, 5, 2]
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>>> heapify(unsorted, 0, len(unsorted))
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>>> unsorted
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[4, 5, 3, 1, 2]
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>>> heapify(unsorted, 0, len(unsorted))
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>>> unsorted
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[5, 4, 3, 1, 2]
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"""
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largest = index
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left_index = 2 * index + 1
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right_index = 2 * index + 2
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if left_index < heap_size and unsorted[left_index] > unsorted[largest]:
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largest = left_index
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if right_index < heap_size and unsorted[right_index] > unsorted[largest]:
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largest = right_index
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if largest != index:
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unsorted[largest], unsorted[index] = (unsorted[index], unsorted[largest])
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heapify(unsorted, largest, heap_size)
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def heap_sort(unsorted: list[int]) -> list[int]:
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"""
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A pure Python implementation of the heap sort algorithm
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:param collection: a mutable ordered collection of heterogeneous comparable items
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:return: the same collection ordered by ascending
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Examples:
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>>> heap_sort([0, 5, 3, 2, 2])
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[0, 2, 2, 3, 5]
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>>> heap_sort([])
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[]
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>>> heap_sort([-2, -5, -45])
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[-45, -5, -2]
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>>> heap_sort([3, 7, 9, 28, 123, -5, 8, -30, -200, 0, 4])
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[-200, -30, -5, 0, 3, 4, 7, 8, 9, 28, 123]
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"""
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n = len(unsorted)
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for i in range(n // 2 - 1, -1, -1):
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heapify(unsorted, i, n)
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for i in range(n - 1, 0, -1):
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unsorted[0], unsorted[i] = unsorted[i], unsorted[0]
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heapify(unsorted, 0, i)
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return unsorted
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if __name__ == "__main__":
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import doctest
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doctest.testmod()
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user_input = input("Enter numbers separated by a comma:\n").strip()
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if user_input:
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unsorted = [int(item) for item in user_input.split(",")]
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print(f"{heap_sort(unsorted) = }")
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