diff --git a/polyalphabetic_cipher b/polyalphabetic_cipher
index bd2209cc0..8771cbffc 100644
--- a/polyalphabetic_cipher
+++ b/polyalphabetic_cipher
@@ -8,14 +8,14 @@ def encrypt(text, key):
     key_index = 0
 
     for char in text:
-        if char.isalpha():  
+        if char.isalpha():
             shift = ord(key[key_index]) - ord('A')
             if char.isupper():
                 new_char = chr((ord(char) - ord('A') + shift) % 26 + ord('A'))
             else:
                 new_char = chr((ord(char) - ord('a') + shift) % 26 + ord('a'))
             encrypted_text.append(new_char)
-            key_index = (key_index + 1) % key_length  
+            key_index = (key_index + 1) % key_length
         else:
             encrypted_text.append(char)
 
@@ -31,14 +31,14 @@ def decrypt(text, key):
     key_index = 0
 
     for char in text:
-        if char.isalpha():  
+        if char.isalpha():
             shift = ord(key[key_index]) - ord('A')
             if char.isupper():
                 new_char = chr((ord(char) - ord('A') - shift) % 26 + ord('A'))
             else:
                 new_char = chr((ord(char) - ord('a') - shift) % 26 + ord('a'))
             decrypted_text.append(new_char)
-            key_index = (key_index + 1) % key_length  
+            key_index = (key_index + 1) % key_length
         else:
             decrypted_text.append(char)