چالش Intercepted Transmissions¶

class CCIR476:
    def __init__(self):
        self.CCIR_MODE = 1  # Default to letter mode
        self.OLD_MODE = 1

    def decode(self, CCIR):
        if CCIR == 0x78: return '\r'  # CR
        if CCIR == 0x6C: return '\n'  # LF
        if CCIR == 0x5C: return ' '   # SP
        if CCIR == 0x0F: return ''    # ALPHA
        if CCIR == 0x33: return ''    # BETA
        if CCIR == 0x66: return ''    # REP
        if CCIR == 0x5A:
            self.CCIR_MODE = 1
            return ''
        if CCIR == 0x36:
            self.CCIR_MODE = 0
            return ''

        if self.CCIR_MODE == 1:
            return self.decode_letter_mode(CCIR)
        else:
            return self.decode_figure_mode(CCIR)

    def decode_letter_mode(self, CCIR):
        letter_mode_mapping = {
            0x47: 'A', 0x72: 'B', 0x1D: 'C', 0x53: 'D', 0x56: 'E', 0x1B: 'F', 0x35: 'G', 0x69: 'H',
            0x4D: 'I', 0x17: 'J', 0x1E: 'K', 0x65: 'L', 0x39: 'M', 0x59: 'N', 0x71: 'O', 0x2D: 'P',
            0x2E: 'Q', 0x55: 'R', 0x4B: 'S', 0x74: 'T', 0x4E: 'U', 0x3C: 'V', 0x27: 'W', 0x3A: 'X',
            0x2B: 'Y', 0x63: 'Z'
        }
        return letter_mode_mapping.get(CCIR, '')

    def decode_figure_mode(self, CCIR):
        figure_mode_mapping = {
            0x2D: '0', 0x2E: '1', 0x27: '2', 0x56: '3', 0x55: '4', 0x74: '5', 0x2B: '6', 0x4E: '7',
            0x4D: '8', 0x71: '9', 0x4B: "'", 0x1B: '!', 0x1D: ':', 0x1E: '(', 0x35: '&', 0x39: '.',
            0x3A: '/', 0x3C: '=', 0x47: '-', 0x53: '$', 0x59: ',', 0x63: '+', 0x65: ')', 0x69: '#',
            0x72: '?'
        }
        return figure_mode_mapping.get(CCIR, '')

def ccir476_decode(binary_string):
    n = 7
    segments = [int(binary_string[i:i+n], 2) for i in range(0, len(binary_string), n)]

    decoder = CCIR476()
    decoded_message = ''.join([decoder.decode(segment) for segment in segments])

    return decoded_message

binary_string = "101101001101101101001110100110110101110100110100101101101010110101110010110100101110100111001101100101101101101000111100011110011011010101011001011101101010010111011100100011110101010110110101011010111001011010110100101101101010110101101011001011010011101110001101100101110101101010110011011100001101101101101010101101101000111010110110010111010110101100101100110111101000101011101110001101101101001010111001011101110001010111001011100011011"
decoded_message = ccir476_decode(binary_string)
print(decoded_message)