Raise ValueError for negative inputs in radix_sort

Author: keerthitn9

sorts/radix_sort.py

@@ -21,7 +21,14 @@ def radix_sort(list_of_ints: list[int]) -> list[int]:
     True
     >>> radix_sort([1,100,10,1000]) == sorted([1,100,10,1000])
     True
+    >>> radix_sort([1, 3, -2, 4])
+    Traceback (most recent call last):
+        ...
+    ValueError: negative integers are not supported
     """
+    if any(i < 0 for i in list_of_ints):
+        raise ValueError("negative integers are not supported")
+
     placement = 1
     max_digit = max(list_of_ints)
     while placement <= max_digit: