mirror of
https://github.com/TheAlgorithms/Python.git
synced 2026-09-28 13:33:11 +08:00
TheRodzzandChristian Clauss
5a6cc4869a
* fix(sorts): raise ValueError for negative inputs in radix_sort (#14950) This commit updates `radix_sort()` to validate that all integers in `list_of_ints` are non-negative. Radix sort relies on digit-by-digit sorting and only supports non-negative integers. If any negative integer is present in `list_of_ints`, `radix_sort()` now raises a `ValueError`. Empty list input is also handled gracefully. Additionally, pre-commit noqa annotations are updated where needed. Fixes #14950 * Apply suggestion from @cclauss --------- Co-authored-by: Christian Clauss <cclauss@me.com>
59 lines
1.5 KiB
Python
59 lines
1.5 KiB
Python
"""
|
|
This is a pure Python implementation of the radix sort algorithm
|
|
|
|
Source: https://en.wikipedia.org/wiki/Radix_sort
|
|
"""
|
|
|
|
from __future__ import annotations
|
|
|
|
RADIX = 10
|
|
|
|
|
|
def radix_sort(list_of_ints: list[int]) -> list[int]:
|
|
"""
|
|
Examples:
|
|
>>> radix_sort([0, 5, 3, 2, 2])
|
|
[0, 2, 2, 3, 5]
|
|
|
|
>>> radix_sort(list(range(15))) == sorted(range(15))
|
|
True
|
|
>>> radix_sort(list(range(14,-1,-1))) == sorted(range(15))
|
|
True
|
|
>>> radix_sort([1,100,10,1000]) == sorted([1,100,10,1000])
|
|
True
|
|
>>> radix_sort([-1, 2, 3])
|
|
Traceback (most recent call last):
|
|
...
|
|
ValueError: All elements in list_of_ints must be non-negative integers
|
|
"""
|
|
if not list_of_ints:
|
|
return []
|
|
|
|
if any(i < 0 for i in list_of_ints):
|
|
raise ValueError("All elements in list_of_ints must be non-negative integers")
|
|
|
|
placement = 1
|
|
max_digit = max(list_of_ints)
|
|
while placement <= max_digit:
|
|
# declare and initialize empty buckets
|
|
buckets: list[list] = [[] for _ in range(RADIX)]
|
|
# split list_of_ints between the buckets
|
|
for i in list_of_ints:
|
|
tmp = int((i / placement) % RADIX)
|
|
buckets[tmp].append(i)
|
|
# put each buckets' contents into list_of_ints
|
|
a = 0
|
|
for b in range(RADIX):
|
|
for i in buckets[b]:
|
|
list_of_ints[a] = i
|
|
a += 1
|
|
# move to next
|
|
placement *= RADIX
|
|
return list_of_ints
|
|
|
|
|
|
if __name__ == "__main__":
|
|
import doctest
|
|
|
|
doctest.testmod()
|