class CreditCardDetector::Luhn
Class to validate Luhn
numbers.
Public Class Methods
valid?(number)
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# File lib/credit_card_detector/luhn.rb, line 4 def self.valid?(number) s1 = s2 = 0 number.to_s.reverse.chars.each_slice(2) do |odd, even| s1 += odd.to_i double = even.to_i * 2 double -= 9 if double >= 10 s2 += double end (s1 + s2) % 10 == 0 end