isbn-verifier: a check digit can only be one character #2604
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BNAndras
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kotp
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ErikSchierboom
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This updates the exercise with new test cases from exercism/problem-specifications#2604 and exercism/problem-specifications#2601.
jagdish-15
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This updates the exercise with new test cases from exercism/problem-specifications#2604 and exercism/problem-specifications#2601.
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A check digit can only be one character, even if the "sum" is divisible by eleven.
Given
3-598-21508-96, suppose we take the weighted sum of the first 9 digits and then add the remaining digits as the "check digit":$ sh -c 'echo $(( (10*3 + 9*5 + 8*9 + 7*8 + 6*2 + 5*1 + 4*5 + 3*0 + 2*8 + 96) % 11 ))' 0It should still be invalid for violating the description:
Forum: http://forum.exercism.org/t/yet-another-isbn-edge-case-found/19787