code enhancement in sort.double_sort (TheAlgorithms#10798)

* don't need to return list because list is mutable

* Don't need to return list as list is mutable
* use advantage of python in swapping
* filter blank inputs from input list
* minor changes

* minor mistake

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* more readable

* Update double_sort.py

* last fixes

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Apply suggestions from code review

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Christian Clauss <[email protected]>

Author: 3 people

sorts/double_sort.py

@@ -1,4 +1,7 @@
-def double_sort(lst):
+from typing import Any
+
+
+def double_sort(collection: list[Any]) -> list[Any]:
     """This sorting algorithm sorts an array using the principle of bubble sort,
     but does it both from left to right and right to left.
     Hence, it's called "Double sort"
@@ -14,29 +17,28 @@ def double_sort(lst):
     >>> double_sort([-3, 10, 16, -42, 29]) == sorted([-3, 10, 16, -42, 29])
     True
     """
-    no_of_elements = len(lst)
+    no_of_elements = len(collection)
     for _ in range(
         int(((no_of_elements - 1) / 2) + 1)
     ):  # we don't need to traverse to end of list as
         for j in range(no_of_elements - 1):
-            if (
-                lst[j + 1] < lst[j]
-            ):  # applying bubble sort algorithm from left to right (or forwards)
-                temp = lst[j + 1]
-                lst[j + 1] = lst[j]
-                lst[j] = temp
-            if (
-                lst[no_of_elements - 1 - j] < lst[no_of_elements - 2 - j]
-            ):  # applying bubble sort algorithm from right to left (or backwards)
-                temp = lst[no_of_elements - 1 - j]
-                lst[no_of_elements - 1 - j] = lst[no_of_elements - 2 - j]
-                lst[no_of_elements - 2 - j] = temp
-    return lst
+            # apply the bubble sort algorithm from left to right (or forwards)
+            if collection[j + 1] < collection[j]:
+                collection[j], collection[j + 1] = collection[j + 1], collection[j]
+            # apply the bubble sort algorithm from right to left (or backwards)
+            if collection[no_of_elements - 1 - j] < collection[no_of_elements - 2 - j]:
+                (
+                    collection[no_of_elements - 1 - j],
+                    collection[no_of_elements - 2 - j],
+                ) = (
+                    collection[no_of_elements - 2 - j],
+                    collection[no_of_elements - 1 - j],
+                )
+    return collection
 
 
 if __name__ == "__main__":
-    print("enter the list to be sorted")
-    lst = [int(x) for x in input().split()]  # inputing elements of the list in one line
-    sorted_lst = double_sort(lst)
+    # allow the user to input the elements of the list on one line
+    unsorted = [int(x) for x in input("Enter the list to be sorted: ").split() if x]
     print("the sorted list is")
-    print(sorted_lst)
+    print(f"{double_sort(unsorted) = }")