Book of Potion Making

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Harry wants to find Voldemort's potion making book but he is confused about how to get it. The book has a special ISBN(International Standard Book Number) which is unique numeric book identifier only for Voldemort's book printed on it. The ISBN is based upon a 10-digit code. The ISBN is valid if: 1xdigit1 + 2xdigit2 + 3xdigit3 + 4xdigit4 + 5xdigit5 + 6xdigit6 + 7xdigit7 + 8xdigit8 + 9xdigit9 + 1

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solution.cppC++17

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