diff --git a/sorts/cocktail_shaker_sort.py b/sorts/cocktail_shaker_sort.py index b738ff31d768..de126426d986 100644 --- a/sorts/cocktail_shaker_sort.py +++ b/sorts/cocktail_shaker_sort.py @@ -1,40 +1,62 @@ -""" https://en.wikipedia.org/wiki/Cocktail_shaker_sort """ +""" +An implementation of the cocktail shaker sort algorithm in pure Python. +https://en.wikipedia.org/wiki/Cocktail_shaker_sort +""" -def cocktail_shaker_sort(unsorted: list) -> list: + +def cocktail_shaker_sort(arr: list[int]) -> list[int]: """ - Pure implementation of the cocktail shaker sort algorithm in Python. + Sorts a list using the Cocktail Shaker Sort algorithm. + + :param arr: List of elements to be sorted. + :return: Sorted list. + >>> cocktail_shaker_sort([4, 5, 2, 1, 2]) [1, 2, 2, 4, 5] - >>> cocktail_shaker_sort([-4, 5, 0, 1, 2, 11]) [-4, 0, 1, 2, 5, 11] - >>> cocktail_shaker_sort([0.1, -2.4, 4.4, 2.2]) [-2.4, 0.1, 2.2, 4.4] - >>> cocktail_shaker_sort([1, 2, 3, 4, 5]) [1, 2, 3, 4, 5] - >>> cocktail_shaker_sort([-4, -5, -24, -7, -11]) [-24, -11, -7, -5, -4] + >>> cocktail_shaker_sort(["elderberry", "banana", "date", "apple", "cherry"]) + ['apple', 'banana', 'cherry', 'date', 'elderberry'] + >>> cocktail_shaker_sort((-4, -5, -24, -7, -11)) + Traceback (most recent call last): + ... + TypeError: 'tuple' object does not support item assignment """ - for i in range(len(unsorted) - 1, 0, -1): + start, end = 0, len(arr) - 1 + + while start < end: swapped = False - for j in range(i, 0, -1): - if unsorted[j] < unsorted[j - 1]: - unsorted[j], unsorted[j - 1] = unsorted[j - 1], unsorted[j] + # Pass from left to right + for i in range(start, end): + if arr[i] > arr[i + 1]: + arr[i], arr[i + 1] = arr[i + 1], arr[i] swapped = True - for j in range(i): - if unsorted[j] > unsorted[j + 1]: - unsorted[j], unsorted[j + 1] = unsorted[j + 1], unsorted[j] + if not swapped: + break + + end -= 1 # Decrease the end pointer after each pass + + # Pass from right to left + for i in range(end, start, -1): + if arr[i] < arr[i - 1]: + arr[i], arr[i - 1] = arr[i - 1], arr[i] swapped = True if not swapped: break - return unsorted + + start += 1 # Increase the start pointer after each pass + + return arr if __name__ == "__main__":