mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-24 05:21:09 +00:00
7f04e5cd34
* spelling corrections * review * improved documentation, removed redundant variables, added testing * added type hint * camel case to snake case * spelling fix * review * python --> Python # it is a brand name, not a snake * explicit cast to int * spaces in int list * "!= None" to "is not None" * Update comb_sort.py * various spelling corrections in documentation & several variables naming conventions fix * + char in file name * import dependency - bug fix Co-authored-by: John Law <johnlaw.po@gmail.com>
53 lines
1.3 KiB
Python
53 lines
1.3 KiB
Python
"""
|
|
This is a pure Python implementation of the merge sort algorithm
|
|
|
|
For doctests run following command:
|
|
python -m doctest -v merge_sort.py
|
|
or
|
|
python3 -m doctest -v merge_sort.py
|
|
|
|
For manual testing run:
|
|
python merge_sort.py
|
|
"""
|
|
|
|
|
|
def merge_sort(collection):
|
|
"""Pure implementation of the merge sort algorithm in Python
|
|
|
|
:param collection: some mutable ordered collection with heterogeneous
|
|
comparable items inside
|
|
:return: the same collection ordered by ascending
|
|
|
|
Examples:
|
|
>>> merge_sort([0, 5, 3, 2, 2])
|
|
[0, 2, 2, 3, 5]
|
|
|
|
>>> merge_sort([])
|
|
[]
|
|
|
|
>>> merge_sort([-2, -5, -45])
|
|
[-45, -5, -2]
|
|
"""
|
|
|
|
def merge(left, right):
|
|
"""merge left and right
|
|
:param left: left collection
|
|
:param right: right collection
|
|
:return: merge result
|
|
"""
|
|
result = []
|
|
while left and right:
|
|
result.append((left if left[0] <= right[0] else right).pop(0))
|
|
return result + left + right
|
|
|
|
if len(collection) <= 1:
|
|
return collection
|
|
mid = len(collection) // 2
|
|
return merge(merge_sort(collection[:mid]), merge_sort(collection[mid:]))
|
|
|
|
|
|
if __name__ == "__main__":
|
|
user_input = input("Enter numbers separated by a comma:\n").strip()
|
|
unsorted = [int(item) for item in user_input.split(",")]
|
|
print(*merge_sort(unsorted), sep=",")
|