Include the Sleep sort

DIRECTORY.md

@@ -993,6 +993,7 @@
   * [Selection Sort](sorts/selection_sort.py)
   * [Shell Sort](sorts/shell_sort.py)
   * [Shrink Shell Sort](sorts/shrink_shell_sort.py)
+  * [Sleep Sort](sorts/sleep_sort.py)
   * [Slowsort](sorts/slowsort.py)
   * [Stooge Sort](sorts/stooge_sort.py)
   * [Strand Sort](sorts/strand_sort.py)

sorts/sleep_sort.py

@@ -0,0 +1,68 @@
+"""
+This is a pure Python implementation of the sleep algorithm,
+In general, sleep sort works by starting a separate task for
+each item to be sorted, where each task sleeps for an interval
+corresponding to the item's sort key, then emits the item.
+Items are then collected sequentially in time.
+
+More info on: https://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort
+
+For doctests run following command:
+python -m doctest -v sleep_sort.py
+or
+python3 -m doctest -v sleep_sort.py
+For manual testing run:
+python sleep_sort.py
+"""
+
+from threading import Timer
+from time import sleep
+
+
+def sleep_sort(collection):
+    """Pure implementation of sleep sort algorithm in Python
+
+    :param collection: some mutable ordered collection with heterogeneous
+    comparable items inside
+    :return: the same collection ordered by ascending
+
+    Examples:
+    >>> sleep_sort([0, 5, 2, 3, 2])
+    [0, 2, 2, 3, 5]
+    >>> sleep_sort([0, 5, 2, 3, 2]) == sorted([0, 5, 2, 3, 2])
+    True
+    >>> sleep_sort([]) == sorted([])
+    True
+    >>> sleep_sort([2, 15, 5]) == sorted([2, 15, 5])
+    True
+    >>> sleep_sort([23, 0, 6, 4, 34]) == sorted([23, 0, 6, 4, 34])
+    True
+    """
+    result = []
+
+    def append_result(x):
+        result.append(x)
+
+    if len(collection) > 0:
+        mx = collection[0]
+        for v in collection:
+            if mx < v:
+                mx = v
+            Timer(v, append_result, [v]).start()
+
+        sleep(mx + 1)
+
+    return result
+
+
+if __name__ == "__main__":
+    import doctest
+    import time
+
+    doctest.testmod()
+
+    user_input = input("Enter numbers separated by a comma:").strip()
+    unsorted = [int(item) for item in user_input.split(",")]
+    start = time.process_time()
+    print(*sleep_sort(unsorted), sep=",")
+    print(f"Processing time: {time.process_time() - start}")