Question

#Vigenere Cipher
EncryptedMessage=""
Mode=""
Keywordcount = 0 #sets everything to 0
KeywordTwocount = 0

while Mode != "encrypt" and Mode != "decrypt":
    Mode = input('Do you want to encrypt or decrypt a message?')
    Mode = Mode.lower()

if Mode == "encrypt":
    Message=input('Please eneter the message you wish to encrypt: ')
    Keyword=input('Please enter the keyword you want to use:')
    KeywordTwo = input(' Please enter second keyword you want to use:') 
    Keywordlength = len(Keyword)
    KeywordTwolength = len(KeywordTwo)

    for i in range(0, len(Message)):
        Messageencrypt = Message[i]
        Keywordencrypt = Keyword[Keywordcount]
        KeywordTwoencrypt= KeywordTwo[KeywordTwocount]
        if Messageencrypt.isalpha():
            if Messageencrypt.isupper():
                Messageencrypt = ord(Messageencrypt)
                Keywordencrypt = Keywordencrypt.upper()
                Keywordencrypt = ord(Keywordencrypt) - 64
                KeywordTwoencrypt = KeywordTwoencrypt.upper()
                KeywordTwoencrypt = ord(Keyword2encrypt) - 64
                FirstCodedMessage = Messageencrypt + Keywordencrypt
                FinalCodedMessage = FirstCodedMessage + Keyword2encrypt
                if FinalCodedMessage > 90:
                    FinalCodedMessage = FinalCodedMessage - 26
                Encryptedletter = chr(FinalCodedMessage)
            elif Messageencrypt.islower():
                Messageencrypt = ord(Messageencrypt)
                Keywordencrypt = Keywordencrypt.upper()
                Keywordencrypt = ord(Keywordencrypt) - 64
                KeywordTwoencrypt = KeywordTwoencrypt.upper()
                KeywordTwoencrypt = ord(KeywordTwoencrypt) - 64
                FinalCodedMessage = Messageencrypt + Keywordencrypt
                if FinalCodedMessage > 122:
                    FinalCodedMessage = FinalCodedMessage - 26
            Encryptedletter = chr(FinalCodedMessage)
        else:
            Encryptedletter = Messageencrypt
        EncryptedMessage = EncryptedMessage + Encryptedletter
        Keywordcount = Keywordcount + 1
        if Keywordcount >= Keywordlength:
            Keywordcount = 0
        KeywordTwocount = KeywordTwocount + 1
        if KeywordTwocount >= Keywordlength:
            KeywordTwocount = 0
    print(EncryptedMessage)

什么是

KeywordTwoencrypt= KeywordTwo[KeywordTwocount]
IndexError: string index out of range

意思？ Error

另外，如何将此加密邮件另存为txt文件？ Error

Answer 1

if KeywordTwocount >= Keywordlength:应为if KeywordTwocount >= KeywordTwolength:

如果存在索引问题，那么您应该仔细查看处理此特定索引增量/减量的代码的所有部分。

在这种特定情况下，您应该看到第二个关键字的索引与第一个关键字的长度无关。所以更新是错误的：

if KeywordTwocount >= Keywordlength:
    KeywordTwocount = 0

通过定义使用一个关键字加密消息的函数，可以轻松避免此错误：

def vigenere(message, keyword):
    ...

然后你可以将这两者连在一起：

print(vigenere(vigenere(message, keyword1), keyword2))

使用内置函数写入文件也很容易：

with open('ciphertext.txt', 'w') as ct:
    ct.write(EncryptedMessage)

Answer 2

KeywordTwo[KeywordTwoCount] IndexError: string index out of range表示索引（KeywordTwoCount）大于您要将KeywordTwo索引的字符串的长度。

什么＆＃34;字符串索引超出范围＆＃34;在这个Vigenere密码中意味着什么？

2 个答案: