Design a way to give a prize to the requester of the billionth request?

Question

Friends i came across this question and believe it to be interview question, but have no idea in this. Please share if you have one

"In a system where millions of users are issuing requests at the same time (e.g. a search engine), design a way to give a prize to the requester of the billionth request?"

Answer 1

You know, for computers, in their innermost core, there is no such concept as "at the same time"...
Each request gets its own unique id and you just start counting from one to one billion :)

Answer 2

Question says design, not make a program. So if you know just give idea, how to tackle this. @Yadumeet

Answer 3

Well, should we make a program and show you