Questions tagged [credit-card-number]

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pset1 credit.c file EMPTY?

this is my first question in this community. I just downloaded the zip file for pset1, problem credit (more comfortable) is the file actually empty ? could it be that I did something wrong? thank you ...
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Cs50 pset1 problem credit

I'm not able to take out the second digit of the credit number, how to do it for large numbers like 16 digit,15digit,14 digit?
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Credit Problem: what does "number’s second-to-last digit" mean?

In the example code on for the Credit problem, it says, Multiply every other digit by 2, starting with the number’s second-to-last digit, and then add those products' digits together. Moverover, the ...
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Pset1 valid visa number as invalid

I built the first part to check whether a number is a valid AMEX number and used the same logic to check for Visa number but the codes don't seem to work as I tried with several valid visa numbers and ...
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Why does this code sometimes give me a different sum when i run it for the same cc number?

I'm working on the credit problem in pset1, and this is only part of what should be done. All I'm trying to do here is to multiply every other number (from the cc number entered by the user) by two, ...
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Why does my code not print every other digit in a long long, and add them together?

Why won't this code print every other digit in a long long number (in this case, it's suppposed to be a credit card number), and add these numbers up? You'll notice I commented out several lines of ...
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