Python/sorts/insertion_sort.py

57 lines
1.4 KiB
Python

"""
This is a pure python implementation of the insertion sort algorithm
For doctests run following command:
python -m doctest -v insertion_sort.py
or
python3 -m doctest -v insertion_sort.py
For manual testing run:
python insertion_sort.py
"""
from __future__ import print_function
def insertion_sort(collection):
"""Pure implementation of the insertion sort algorithm in Python
:param collection: some mutable ordered collection with heterogeneous
comparable items inside
:return: the same collection ordered by ascending
Examples:
>>> insertion_sort([0, 5, 3, 2, 2])
[0, 2, 2, 3, 5]
>>> insertion_sort([])
[]
>>> insertion_sort([-2, -5, -45])
[-45, -5, -2]
"""
length = len(collection)
for i in range(length):
current_item = collection[i]
j = i - 1
while j >= 0 and current_item < collection[j]:
collection[j+1] = collection[j]
j -= 1
collection[j+1] = current_item
return collection
if __name__ == '__main__':
import sys
# For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
# otherwise 2.x's input builtin function is too "smart"
if sys.version_info.major < 3:
input_function = raw_input
else:
input_function = input
user_input = input_function('Enter numbers separated by a comma:\n')
unsorted = [int(item) for item in user_input.split(',')]
print(insertion_sort(unsorted))