How to generate unique number of 12 digits?

Question

I\'m working on an app that sends raw data to zebra printer and print out barcodes. And since every item has its own unique barcode, I need to define a variable that automat

Answer 1

Using an RNG and a hash do:

10 - stream out 12 digits
20 - check if value is in hash
30 - if it's goto 40 else goto 10
40 - push value into hash
50 - return new 12 digit number
60 - goto 10