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86 lines
3.0 KiB
Python
86 lines
3.0 KiB
Python
#https://en.wikipedia.org/wiki/Trifid_cipher
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def __encryptPart(messagePart, character2Number):
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one, two, three = "", "", ""
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tmp = []
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for character in messagePart:
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tmp.append(character2Number[character])
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for each in tmp:
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one += each[0]
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two += each[1]
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three += each[2]
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return one+two+three
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def __decryptPart(messagePart, character2Number):
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tmp, thisPart = "", ""
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result = []
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for character in messagePart:
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thisPart += character2Number[character]
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for digit in thisPart:
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tmp += digit
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if len(tmp) == len(messagePart):
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result.append(tmp)
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tmp = ""
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return result[0], result[1], result[2]
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def __prepare(message, alphabet):
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#Validate message and alphabet, set to upper and remove spaces
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alphabet = alphabet.replace(" ", "").upper()
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message = message.replace(" ", "").upper()
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#Check length and characters
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if len(alphabet) != 27:
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raise KeyError("Length of alphabet has to be 27.")
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for each in message:
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if each not in alphabet:
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raise ValueError("Each message character has to be included in alphabet!")
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#Generate dictionares
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numbers = ("111","112","113","121","122","123","131","132","133","211","212","213","221","222","223","231","232","233","311","312","313","321","322","323","331","332","333")
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character2Number = {}
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number2Character = {}
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for letter, number in zip(alphabet, numbers):
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character2Number[letter] = number
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number2Character[number] = letter
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return message, alphabet, character2Number, number2Character
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def encryptMessage(message, alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ.", period=5):
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message, alphabet, character2Number, number2Character = __prepare(message, alphabet)
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encrypted, encrypted_numeric = "", ""
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for i in range(0, len(message)+1, period):
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encrypted_numeric += __encryptPart(message[i:i+period], character2Number)
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for i in range(0, len(encrypted_numeric), 3):
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encrypted += number2Character[encrypted_numeric[i:i+3]]
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return encrypted
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def decryptMessage(message, alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ.", period=5):
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message, alphabet, character2Number, number2Character = __prepare(message, alphabet)
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decrypted_numeric = []
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decrypted = ""
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for i in range(0, len(message)+1, period):
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a,b,c = __decryptPart(message[i:i+period], character2Number)
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for j in range(0, len(a)):
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decrypted_numeric.append(a[j]+b[j]+c[j])
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for each in decrypted_numeric:
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decrypted += number2Character[each]
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return decrypted
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if __name__ == '__main__':
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msg = "DEFEND THE EAST WALL OF THE CASTLE."
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encrypted = encryptMessage(msg,"EPSDUCVWYM.ZLKXNBTFGORIJHAQ")
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decrypted = decryptMessage(encrypted, "EPSDUCVWYM.ZLKXNBTFGORIJHAQ")
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print ("Encrypted: {}\nDecrypted: {}".format(encrypted, decrypted)) |