Comb sort is a relatively simple sorting algorithm originally designed by Włodzimierz Dobosiewicz and Artur Borowy in 1980, later rediscovered by Stephen Lacey and Richard box in 1991.Comb sort improves on bubble sort.

The basic idea is to eliminate turtles, or small values near the end of the list, since in a bubble sort these slow the sorting down tremendously. The inner loop of bubble sort, which makes the actual swap, is modify such that the gap between swapped components goes down (for each iteration of outer loop) in steps of a" shrink factor" K: [ N / K, N / k2, N

```
"""
This is pure Python implementation of comb sort algorithm.
Comb sort is a relatively simple sorting algorithm originally designed by Wlodzimierz Dobosiewicz in 1980.
It was rediscovered by Stephen Lacey and Richard Box in 1991. Comb sort improves on bubble sort algorithm.
In bubble sort, distance (or gap) between two compared elements is always one.
Comb sort improvement is that gap can be much more than 1, in order to prevent slowing down by small values
at the end of a list.
More info on: https://en.wikipedia.org/wiki/Comb_sort
For doctests run following command:
python -m doctest -v comb_sort.py
or
python3 -m doctest -v comb_sort.py
For manual testing run:
python comb_sort.py
"""
def comb_sort(data: list) -> list:
"""Pure implementation of comb sort algorithm in Python
:param data: mutable collection with comparable items
:return: the same collection in ascending order
Examples:
>>> comb_sort([0, 5, 3, 2, 2])
[0, 2, 2, 3, 5]
>>> comb_sort([])
[]
>>> comb_sort([99, 45, -7, 8, 2, 0, -15, 3])
[-15, -7, 0, 2, 3, 8, 45, 99]
"""
shrink_factor = 1.3
gap = len(data)
completed = False
while not completed:
# Update the gap value for a next comb
gap = int(gap / shrink_factor)
if gap <= 1:
completed = True
index = 0
while index + gap < len(data):
if data[index] > data[index + gap]:
# Swap values
data[index], data[index + gap] = data[index + gap], data[index]
completed = False
index += 1
return data
if __name__ == "__main__":
import doctest
doctest.testmod()
user_input = input("Enter numbers separated by a comma:\n").strip()
unsorted = [int(item) for item in user_input.split(",")]
print(comb_sort(unsorted))
```