# C# - Luhn Check Digit / Produces 2 Length Check Digit Values?

Jun 26, 2010

I cant seem to figure out what is wrong with my check digit code!

At times, it produces 2 length check digit values

Example

1277531815000110 <-- check digit is double value??????
1277532495000110 <-- check digit is double value???????
1277534649000110 <-- check digit is double value???????
127753185300011 <-- good!
127753208500019 <-- good!

All generated numbers are valid, it can be checked at http://www.ee.unb.ca/cgi-bin/tervo/luhn.pl?N=127753224800013

CODE: http://tinyurl.com/352acpj

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