Refactor cycle_sort (TheAlgorithms#2072)

* Refactor cycle_sort

* Undo changes to keep only doctests

Author: l3str4nge

sorts/cycle_sort.py

@@ -1,5 +1,23 @@
-# Code contributed by Honey Sharma
-def cycle_sort(array):
+"""
+Code contributed by Honey Sharma
+Source: https://en.wikipedia.org/wiki/Cycle_sort
+"""
+
+
+def cycle_sort(array: list) -> list:
+    """
+    >>> cycle_sort([4, 3, 2, 1])
+    [1, 2, 3, 4]
+
+    >>> cycle_sort([-4, 20, 0, -50, 100, -1])
+    [-50, -4, -1, 0, 20, 100]
+
+    >>> cycle_sort([-.1, -.2, 1.3, -.8])
+    [-0.8, -0.2, -0.1, 1.3]
+
+    >>> cycle_sort([])
+    []
+    """
     ans = 0
 
     # Pass through the array to find cycles to rotate.
@@ -37,16 +55,9 @@ def cycle_sort(array):
             array[pos], item = item, array[pos]
             ans += 1
 
-    return ans
+    return array
 
 
-#  Main Code starts here
 if __name__ == "__main__":
-    user_input = input("Enter numbers separated by a comma:\n")
-    unsorted = [int(item) for item in user_input.split(",")]
-    n = len(unsorted)
-    cycle_sort(unsorted)
-
-    print("After sort : ")
-    for i in range(0, n):
-        print(unsorted[i], end=" ")
+    assert cycle_sort([4, 5, 3, 2, 1]) == [1, 2, 3, 4, 5]
+    assert cycle_sort([0, 1, -10, 15, 2, -2]) == [-10, -2, 0, 1, 2, 15]