Here is an example. There is Master Computer, It Looks At Your ID # and Answer Key , It lets you pass once they match with Master Computer's Internal Algorithm. Your Answer Key given to you by looking at your ID#, Master Computer Does not have database of ID#'s and Answer Keys because any given time new ones can be created. So there is Algorithm. I get hold of few ID# and Answer Key's and I Want to find what Algorithm they used creating the master formula. For Example. Machine 1 ID : 765567 - Answer Key : ACB6767BCA Machine 2 ID : 324234 - Answer Key : DC1BHJ98BK Both Answer Keys Created by looking at machine ID's and by knowing many of them can i come up with Answer Key generator? I want to be able to Enter Machine ID and I want to create Answer Key that matches Master Computer's Formula. How many Machine ID's and Answer key's should i get hold of in order to figure what algorithm it uses?