29 lines
589 B
Python
29 lines
589 B
Python
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import string
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LOWERCASE_OFFSET = ord("a")
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ALPHABET = string.ascii_lowercase[:16]
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def b16_encode(plain):
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enc = ""
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for c in plain:
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binary = "{0:08b}".format(ord(c))
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enc += ALPHABET[int(binary[:4], 2)]
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enc += ALPHABET[int(binary[4:], 2)]
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return enc
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def shift(c, k):
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t1 = ord(c) - LOWERCASE_OFFSET
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t2 = ord(k) - LOWERCASE_OFFSET
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return ALPHABET[(t1 + t2) % len(ALPHABET)]
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flag = "redacted"
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key = "redacted"
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assert all([k in ALPHABET for k in key])
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assert len(key) == 1
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b16 = b16_encode(flag)
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enc = ""
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for i, c in enumerate(b16):
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enc += shift(c, key[i % len(key)])
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print(enc)
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