Add Solution

python/solution.py

@@ -0,0 +1,45 @@
+import string
+
+def prepare_key(key):
+    key = key.upper().replace('J', 'I')
+    return ''.join(dict.fromkeys(key + string.ascii_uppercase.replace('J', '')))
+
+def create_matrix(key):
+    return [list(key[i:i+5]) for i in range(0, 25, 5)]
+
+def find_position(matrix, letter):
+    for i, row in enumerate(matrix):
+        if letter in row:
+            return i, row.index(letter)
+    return None
+
+def decrypt_playfair(ciphertext, key):
+    prepared_key = prepare_key(key)
+    matrix = create_matrix(prepared_key)
+    ciphertext = ciphertext.upper().replace('J', 'I')
+    plaintext = ""
+
+    for i in range(0, len(ciphertext), 2):
+        a, b = ciphertext[i], ciphertext[i+1]
+        row1, col1 = find_position(matrix, a)
+        row2, col2 = find_position(matrix, b)
+
+        if row1 == row2:
+            plaintext += matrix[row1][(col1-1)%5] + matrix[row2][(col2-1)%5]
+        elif col1 == col2:
+            plaintext += matrix[(row1-1)%5][col1] + matrix[(row2-1)%5][col2]
+        else:
+            plaintext += matrix[row1][col2] + matrix[row2][col1]
+
+    return plaintext.replace('X','')
+
+def process_cipher(key, ciphertext):
+    decrypted_text = decrypt_playfair(ciphertext, key)
+    return decrypted_text
+
+if __name__ == "__main__":
+    secret_key = "SUPERSPY"
+    encrypted_message = "IKEWENENXLNQLPZSLERUMRHEERYBOFNEINCHCV"
+
+    result = process_cipher(secret_key, encrypted_message)
+    print(result, end='')