86 lines
2.0 KiB
Python
86 lines
2.0 KiB
Python
def encode(m):
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message = format(int.from_bytes(m.encode("latin-1"), "big"), "b")
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generator = "10001000000100001"
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gen_deg = len(generator)
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message += "0" * (gen_deg - 1)
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while len(message) % 8 != 0:
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message = "0" + message
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swapped = list(message)
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for i in range(gen_deg - 1):
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if swapped[i] == "0":
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swapped[i] = "1"
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else:
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swapped[i] = "0"
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message = "".join(swapped)
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while True:
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if message[0] == "0":
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message = message[1:]
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else:
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chunk = message[:gen_deg]
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if len(chunk) < gen_deg:
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while len(chunk) % 8 != 0:
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chunk = "0" + chunk
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return m + chr(int(chunk[:8], 2)) + chr(int(chunk[8:], 2))
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remainder = format(int(chunk, 2) ^ int(generator, 2), "b")
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message = remainder + message[gen_deg:]
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def decode(n):
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message = format(int.from_bytes(n.encode("latin-1"), "big"), "b")
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generator = "10001000000100001"
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gen_deg = len(generator)
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while len(message) % 8 != 0:
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message = "0" + message
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swapped = list(message)
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for i in range(gen_deg - 1):
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if swapped[i] == "0":
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swapped[i] = "1"
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else:
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swapped[i] = "0"
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message = "".join(swapped)
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while True:
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if '1' not in message:
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return True
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if message[0] == "0":
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message = message[1:]
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else:
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chunk = message[:gen_deg]
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if len(chunk) < gen_deg:
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return False
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remainder = format(int(chunk, 2) ^ int(generator, 2), "b")
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message = remainder + message[gen_deg:]
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if __name__ == "__main__":
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choice = ""
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while choice != "3":
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choice = input("1. Utwórz FCS\n2. Sprawdź FCS\n3. Wyjdź\n")
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if choice == "1":
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inp = input("Wprowadź wiadomość:\n")
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print(encode(inp))
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elif choice == "2":
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inp = input("Wprowadź wiadomość z ramką:\n")
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print(decode(inp))
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