Add another implementation (#802)

* Add tests for rotate.py

* Add another implementation

Author: bhanu-pappala

algorithms/strings/rotate.py

@@ -17,3 +17,7 @@ def rotate(s, k):
         return long_string[k:k + len(s)]
     else:
         return long_string[k-len(s):k]
+    
+def rotate_alt(string, k):
+    k = k % len(string)
+    return string[k:] + string[:k]

tests/test_strings.py

@@ -225,6 +225,12 @@ def test_rotate(self):
         self.assertEqual("hello", rotate("hello", 5))
         self.assertEqual("elloh", rotate("hello", 6))
         self.assertEqual("llohe", rotate("hello", 7))
+        
+    def test_rotate_alt(self):
+        self.assertEqual("llohe", rotate_alt("hello", 2))
+        self.assertEqual("hello", rotate_alt("hello", 5))
+        self.assertEqual("elloh", rotate_alt("hello", 6))
+        self.assertEqual("llohe", rotate_alt("hello", 7))
 
 
 class TestLicenseNumber(unittest.TestCase):