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Decoders · difficulty 2 of 3

ISBN-10 validator 📚

An ISBN-10 is valid if the weighted sum (10 x first digit + 9 x second ... + 1 x last, where a final X counts as 10) is divisible by 11. Print True or False.

This one is part of Pro. Plenty of arcade challenges are free to play right now.

Skills: strings, dicts, regex

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