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58 lines
1.5 KiB
Python
58 lines
1.5 KiB
Python
"""
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Python implementation of a sort algorithm.
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Best Case Scenario : O(n)
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Worst Case Scenario : O(n^2) because native Python functions:min, max and remove are
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already O(n)
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"""
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from typing import Protocol
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class Comparable(Protocol):
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def __lt__(self, other: object, /) -> bool: ...
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def merge_sort[T: Comparable](collection: list[T]) -> list[T]:
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"""Pure implementation of the fastest merge sort algorithm in Python
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:param collection: some mutable ordered collection with heterogeneous
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comparable items inside
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:return: a collection ordered by ascending
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Examples:
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>>> merge_sort([0, 5, 3, 2, 2])
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[0, 2, 2, 3, 5]
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>>> merge_sort([])
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[]
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>>> merge_sort([-2, -5, -45])
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[-45, -5, -2]
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>>> merge_sort(['d', 'a', 'b', 'e']) == sorted(['d', 'a', 'b', 'e'])
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True
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>>> merge_sort([1.1, 3.3, 5.5, 2.2, 4.4])
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[1.1, 2.2, 3.3, 4.4, 5.5]
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>>> merge_sort([1, "a"]) # doctest: +IGNORE_EXCEPTION_DETAIL
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Traceback (most recent call last):
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...
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TypeError: '<' not supported between instances of 'str' and 'int'
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"""
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start, end = [], []
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while len(collection) > 1:
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min_one, max_one = min(collection), max(collection)
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start.append(min_one)
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end.append(max_one)
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collection.remove(min_one)
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collection.remove(max_one)
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end.reverse()
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return start + collection + end
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if __name__ == "__main__":
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user_input = input("Enter numbers separated by a comma:\n").strip()
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unsorted = [int(item) for item in user_input.split(",")]
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print(*merge_sort(unsorted), sep=",")
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