Morse code bruteforce

morse_bruteforce.py

MORSE_TRANSLATION = {
    ".-": "A",
    "-...": "B",
    "-.-.": "C",
    "-..": "D",
    ".": "E",
    "..-.": "F",
    "--.": "G",
    "....": "H",
    "..": "I",
    ".---": "J",
    "-.-": "K",
    ".-..": "L",
    "--": "M",
    "-.": "N",
    "---": "O",
    ".--.": "P",
    "--.-": "Q",
    ".-.": "R",
    "...": "S",
    "-": "T",
    "..-": "U",
    "...-": "V",
    ".--": "W",
    "-..-": "X",
    "-.--": "Y",
    "--..": "Z",
}
MAX_MORSE_CODE_SIZE = len(max(MORSE_TRANSLATION.keys(), key=len))


def _all_options(n, options, road):
    for option in options:
        if n - option == 0:
            yield road + [option]
            return []
        elif n - option < 0:
            return []

        yield from _all_options(n - option, options, road + [option])


def all_options(n, options, road=None):
    if road is None:
        road = []
    yield from _all_options(n, sorted(options), road)


def translate_from_morse(morse, option):
    sentence = ''
    for letter_pos in option:
        letter, morse = morse[:letter_pos], morse[letter_pos:]
        sentence += MORSE_TRANSLATION[letter]
    return sentence


def morse_bruteforce(morse):
    for option in all_options(len(morse), range(1, MAX_MORSE_CODE_SIZE + 1)):
        yield translate_from_morse(morse, option)


if __name__ == '__main__':
    assert len(list(all_options(10, range(1, 3)))) == 89
    assert translate_from_morse('.....', [1] * 5) == 'EEEEE'
    assert translate_from_morse('.....', [3, 2]) == 'SI'
    assert 'YAY' in morse_bruteforce("-.--.--.--")