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LuhnAlgorithm

Checks if a group of numbers will pass the Luhn Algorithm.

|Luhn Algorithm by Brian O., 07/15/19 |

The Luhn Algorithm is commonly used to verify credit card numbers, IMEI numbers, etc... Luhn makes it possible to check numbers (credit card, SIRET, etc.) via a control key (called checksum, it is a number of the number which makes it possible to check the others). If a character is incorrect, then Luhn's algorithm will detect the error. Starting with the right-most digit, double every other digit to the left of it. Then all of the undoubled and doubled digits together. If the total is a multiple of 10, then the number passes the Luhn Algorithm. For Luhn to be true: (double digits + undoubled digits) % 10 == 0