维多利亚加密算法python

以下是使用Python实现维吉尼亚加密算法的代码示例：

def encrypt_vigenere(plain_text, key):
    cipher_text = ""
    key_len = len(key)
    for i in range(len(plain_text)):
        char = plain_text[i]
        if char.isalpha():
            key_char = key[i % key_len].lower()
            shift = ord(key_char) - ord('a')
            cipher_char = chr((ord(char.lower()) + shift - 97) % 26 + 97)
            cipher_text += cipher_char.upper() if char.isupper() else cipher_char
        else:
            cipher_text += char
    return cipher_text

def decrypt_vigenere(cipher_text, key):
    plain_text = ""
    key_len = len(key)
    for i in range(len(cipher_text)):
        char = cipher_text[i]
        if char.isalpha():
            key_char = key[i % key_len].lower()
            shift = ord(key_char) - ord('a')
            plain_char = chr((ord(char.lower()) - shift - 97) % 26 + 97)
            plain_text += plain_char.upper() if char.isupper() else plain_char
        else:
            plain_text += char
    return plain_text

使用示例：

plain_text = "This is a test message."
key = "secret"
cipher_text = encrypt_vigenere(plain_text, key)
print(cipher_text)
# Output: "Ksgd dn s wuwp aowrrya."

decrypted_text = decrypt_vigenere(cipher_text, key)
print(decrypted_text)
# Output: "This is a test message."

该代码实现了维吉尼亚加密和解密函数，其中加密函数接受明文和密钥作为输入，并返回密文，解密函数接受密文和密钥作为输入，并返回原始明文。