EANS = [
    "4932413071222",
    "9215337181228",
    "4055572232713",
    "3177777536937",
    "5194353145886",
    "8022631001531",
    "2177559451930",
    "9375914288310",
]

ISBNS = [
    "0-024-00310-7",
    "0-238-30610-0",
    "3-505-52102-7",
    "0-022-11111-5",
    "6-052-75101-0",
    "8-323-17020-7",
    "6-422-29100-0",
    "5-112-73112-5",
]

cards = [
    "5217804766545209",
    "4885373827486781",
    "5839899598496843",
    "9587981988999895",
    "8837998849894933",
    "8986989999966281",
    "9999992947693935",
    "9999489398999945",
]


def decode_ean(ean):
    digits = [int(c) for c in ean[:12]]
    total = 0
    for i, d in enumerate(digits):
        if i % 2 != 0:
            total += d * 3
        else:
            total += d
    return chr(total)


def decode_isbn(isbn):
    digits = [int(c) for c in isbn.replace("-", "")[:9]]
    total = sum((i + 1) * d for i, d in enumerate(digits))
    return chr(total)


def decode_credit_card(cc):
    digits = [int(c) for c in cc[:15]]
    total = 0
    for idx in range(14, -1, -1):
        d = digits[14 - idx]
        weight = 14 - idx
        if weight % 2 != 0:
            total += d
        else:
            doubled = 2 * d
            total += doubled - 9 if doubled > 9 else doubled
    return chr(total)


part1 = "".join(decode_ean(i) for i in EANS)
part2 = "".join(decode_isbn(i) for i in ISBNS)
part3 = "".join(decode_credit_card(c) for c in cards)


print(part1 + part2 + part3)