34 lines
1.1 KiB
Python
34 lines
1.1 KiB
Python
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from string import ascii_lowercase,punctuation,whitespace,digits
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from time import time
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import random
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class Cipher:
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def __init__(self, k=None):
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if k:
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self.key = k.translate(None,punctuation+whitespace+digits).lower()
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else:
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random.seed(time())
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self.key = ''.join(random.choice(ascii_lowercase) for i in range(100))
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def base_encode(self, s, shift):
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xkey = self.key*(len(s)//len(self.key)+1)
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return ''.join(shift(c,k) for c,k in zip(s,xkey))
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def encode(self, s):
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s = s.translate(None,punctuation+whitespace+digits).lower()
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shift = lambda c,k: chr(((ord(c)+ord(k)-2*ord('a'))\
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% len(ascii_lowercase)) + ord('a'))
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return self.base_encode(s, shift)
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def decode(self, s):
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shift = lambda c,k: chr(((ord(c)-ord(k)+len(ascii_lowercase))\
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% len(ascii_lowercase)) + ord('a'))
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return self.base_encode(s, shift)
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class Caesar(Cipher):
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def __init__(self):
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Cipher.__init__(self, 'd')
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if __name__ == '__main__':
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print(Caesar().encode('venividivici'))
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print(Caesar().encode('\'Twas the night before Christmas'))
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