mathdatech/Python
1
0
Fork 0
mirror of https://github.com/TheAlgorithms/Python.git synced 2024-11-24 05:21:09 +00:00
Code Issues Packages Projects Releases Wiki Activity

Optimization for shell sort (#4038)

Browse Source 
* fixed shell sort

* udpate code style

* Update sorts/shell_sort.py

Co-authored-by: John Law <johnlaw.po@gmail.com>

Co-authored-by: John Law <johnlaw.po@gmail.com>
This commit is contained in:
Du Yuanchao 2020-12-18 17:39:51 +08:00 committed by GitHub
parent ae8a5f8675
commit 53371b2381
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 9 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
sorts/shell_sort.py
View File

@ -1,13 +1,5 @@
"""
This is a pure Python implementation of the shell sort algorithm
For doctests run following command:
python -m doctest -v shell_sort.py
or
python3 -m doctest -v shell_sort.py
For manual testing run:
python shell_sort.py
https://en.wikipedia.org/wiki/Shellsort#Pseudocode
"""
@ -19,26 +11,29 @@ def shell_sort(collection):
>>> shell_sort([0, 5, 3, 2, 2])
[0, 2, 2, 3, 5]
>>> shell_sort([])
[]
>>> shell_sort([-2, -5, -45])
[-45, -5, -2]
"""
# Marcin Ciura's gap sequence
gaps = [701, 301, 132, 57, 23, 10, 4, 1]
gaps = [701, 301, 132, 57, 23, 10, 4, 1]
for gap in gaps:
for i in range(gap, len(collection)):
insert_value = collection[i]
j = i
while j >= gap and collection[j] < collection[j - gap]:
collection[j], collection[j - gap] = collection[j - gap], collection[j]
while j >= gap and collection[j - gap] > insert_value:
collection[j] = collection[j - gap]
j -= gap
collection[j] = insert_value
return collection
if __name__ == "__main__":
from doctest import testmod
testmod()
user_input = input("Enter numbers separated by a comma:\n").strip()
unsorted = [int(item) for item in user_input.split(",")]
print(shell_sort(unsorted))