Fix empty input edge case and correct output formatting (#14444)

* Fix empty input edge case and correct output formatting

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

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

* Update pigeonhole_sort.py

* Update pigeonhole_sort.py

* Update pigeonhole_sort.py

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Maxim Smolskiy <mithridatus@mail.ru>

Author: 3 people

sorts/pigeonhole_sort.py

@@ -10,7 +10,11 @@ def pigeonhole_sort(a):
     >>> pigeonhole_sort(a)  # a destructive sort
     >>> a == b
     True
+
+    >>> pigeonhole_sort([])
     """
+    if not a:
+        return
     # size of range of values in the list (ie, number of pigeonholes we need)
 
     min_val = min(a)  # min() finds the minimum value
@@ -38,7 +42,7 @@ def pigeonhole_sort(a):
 def main():
     a = [8, 3, 2, 7, 4, 6, 8]
     pigeonhole_sort(a)
-    print("Sorted order is:", " ".join(a))
+    print("Sorted order is:", *a)
 
 
 if __name__ == "__main__":