Whereas you don't publish the divisors and remainders used to check each field, the fact that a correct field is highlighted in green on completion means that the experimentation required to crack these values is very light. It takes less than half an hour to crack the whole system. I would force the user to finish entering all 12 characters before giving the green (or red) light.

I suggest also changeing the divisors and remainders when you have secured the system.

One world, one people

In reply to Re: RFC: Algorithm::CouponCode by anonymized user 468275
in thread RFC: Algorithm::CouponCode by grantm

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