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

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

Author: pre-commit-ci[bot]

ciphers/hill_cipher.py

@@ -50,33 +50,34 @@ def replace_digits(self, num: int) -> str:
         Convert numerical value to its character equivalent.
         """
         return self.key_string[num]
+
     def integer_determinant(self, matrix: np.ndarray) -> int:
         """
         Calculate determinant of an integer matrix using exact arithmetic.
         """
         n = matrix.shape[0]
-        
+
         # Base case for 1x1 matrix
         if n == 1:
             return matrix[0, 0]
-        
+
         # Base case for 2x2 matrix
         if n == 2:
             return matrix[0, 0] * matrix[1, 1] - matrix[0, 1] * matrix[1, 0]
-        
+
         det = 0
         for j in range(n):
             # Create minor matrix by removing first row and j-th column
             minor = matrix[1:, :]
             minor = np.delete(minor, j, axis=1)
-            
+
             # Recursively calculate determinant of minor
             minor_det = self.integer_determinant(minor)
-            
+
             # Calculate cofactor with sign
             sign = (-1) ** j
             det += sign * matrix[0, j] * minor_det
-            
+
         return det
 
     def check_determinant(self) -> None:
@@ -89,7 +90,7 @@ def check_determinant(self) -> None:
             ValueError: If determinant is not coprime with 36
         """
         det = self.integer_determinant(self.encrypt_key)
-        
+
         # Ensure positive modulo value
         det_mod = det % len(self.key_string)
         if det_mod == 0:
@@ -107,14 +108,14 @@ def process_text(self, text: str) -> str:
         Prepare text for encryption/decryption.
         """
         chars = [char for char in text.upper() if char in self.key_string]
-        
+
         if not chars:
             return ""
-            
+
         last = chars[-1]
         while len(chars) % self.break_key != 0:
             chars.append(last)
-            
+
         return "".join(chars)
 
     def encrypt(self, text: str) -> str:
@@ -124,17 +125,17 @@ def encrypt(self, text: str) -> str:
         text = self.process_text(text.upper())
         if not text:
             return ""
-            
+
         encrypted = ""
 
         for i in range(0, len(text), self.break_key):
-            batch = text[i:i+self.break_key]
+            batch = text[i : i + self.break_key]
             vec = [self.replace_letters(char) for char in batch]
             batch_vec = np.array(vec).reshape(-1, 1)
-            
+
             product = self.encrypt_key @ batch_vec
             batch_encrypted = self.modulus(product).flatten().astype(int)
-            
+
             encrypted_batch = "".join(
                 self.replace_digits(num) for num in batch_encrypted
             )
@@ -149,7 +150,7 @@ def make_decrypt_key(self) -> np.ndarray:
         n = self.break_key
         det = self.integer_determinant(self.encrypt_key)
         modulus = len(self.key_string)
-        
+
         # Find modular inverse of determinant
         det_mod = det % modulus
         det_inv = None
@@ -163,7 +164,7 @@ def make_decrypt_key(self) -> np.ndarray:
 
         # Compute adjugate matrix
         adjugate = np.zeros((n, n), dtype=int)
-        
+
         for i in range(n):
             for j in range(n):
                 minor = np.delete(self.encrypt_key, i, axis=0)
@@ -183,18 +184,18 @@ def decrypt(self, text: str) -> str:
         text = self.process_text(text.upper())
         if not text:
             return ""
-            
+
         decrypt_key = self.make_decrypt_key()
         decrypted = ""
 
         for i in range(0, len(text), self.break_key):
-            batch = text[i:i+self.break_key]
+            batch = text[i : i + self.break_key]
             vec = [self.replace_letters(char) for char in batch]
             batch_vec = np.array(vec).reshape(-1, 1)
-            
+
             product = decrypt_key @ batch_vec
             batch_decrypted = self.modulus(product).flatten().astype(int)
-            
+
             decrypted_batch = "".join(
                 self.replace_digits(num) for num in batch_decrypted
             )
@@ -203,7 +204,6 @@ def decrypt(self, text: str) -> str:
         return decrypted
 
 
-
 def main() -> None:
     """
     Command-line interface for Hill Cipher operations.
@@ -213,14 +213,14 @@ def main() -> None:
 
     print("Enter each row of the encryption key with space separated integers")
     for i in range(n):
-        row = [int(x) for x in input(f"Row {i+1}: ").split()]
+        row = [int(x) for x in input(f"Row {i + 1}: ").split()]
         hill_matrix.append(row)
 
     hc = HillCipher(np.array(hill_matrix))
 
     print("\nWould you like to encrypt or decrypt some text?")
     option = input("1. Encrypt\n2. Decrypt\nEnter choice (1/2): ")
-    
+
     if option == "1":
         text = input("\nEnter text to encrypt: ")
         print("\nEncrypted text:")
@@ -235,20 +235,21 @@ def main() -> None:
 
 if __name__ == "__main__":
     import doctest
+
     doctest.testmod()
-    
+
     print("\nRunning sample tests...")
     key = np.array([[2, 5], [1, 6]])
     cipher = HillCipher(key)
-    
+
     # Test encryption/decryption round trip
     plaintext = "HELLO123"
     encrypted = cipher.encrypt(plaintext)
     decrypted = cipher.decrypt(encrypted)
-    
+
     print(f"\nOriginal text: {plaintext}")
     print(f"Encrypted text: {encrypted}")
     print(f"Decrypted text: {decrypted}")
-    
+
     # Run CLI interface
     main()