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alphabet_eng = "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"
alphabet_rus = "абвгдеёжзийклмнопрстуфхцчшщъыьэюяабвгдеёжзийклмнопрстуфхцчшщъыьэюя"

alph_eng=['A','B"','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']
alph_rus=['А','Б','В','Г','Д','Е','Ж','З','И','Й','К','Л','М','Н','О','П','Р','С','Т','У','Ф','Х','Ц','Ч','Ш','Щ','Ъ','Ы','Ь','Э','Ю','Я']
message=str(input("Введите сообщение: "))
key=int(input("Введите ключ шифра: "))
message = message.upper()
message_enc = ""

for x in message:
#    position = alphabet_eng.find(x)
#    offset = position+key
    if x in alph_eng:
#        message_enc = message_enc + alphabet_eng[offset+1]
        itr = alph_eng.index(x)%len(alph_eng)
        message_enc += alph_eng[(itr+key+1)%len(alph_eng)]
    elif x in alphabet_rus:
        position = alphabet_rus.find(x)
#        offset = position+key
#        message_enc = message_enc + alphabet_rus[offset+1]
        itr = alph_rus.index(x)%len(alph_rus)
        message_enc += alph_rus[(itr+key+1)%len(alph_rus)]
    else:
        message_enc = message_enc + x
message_enc = message_enc.lower()
print("Зашифрованное сообщение: ",message_enc)

    

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