forked from course-work/week1
28 lines
706 B
Python
28 lines
706 B
Python
def char_shift(char, shift):
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start = ord('a') if char.isupper() else ord('A')
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char = ord(char) - start
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shift = (char + shift) % 26
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return chr(shift + start)
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def caesar(message, shift):
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out = ''
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for letter in message:
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if letter.isalpha():
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letter = char_shift(letter, shift)
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out += letter
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# or in one line
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# out += char_shift(letter, shift) if letter.isalpha() else letter
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return out
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def decrypt_caesar(message, shift):
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return caesar(message, shift - (shift * 2))
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# Add your own assert statements to test your code.
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sentence = 'But the Caesar Cipher is [still used](http://en.wikipedia.org/wiki/ROT13)'
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shift = 300
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assert( decrypt_caesar(caesar(sentence, shift), 300) == sentence )
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