Right so – that wasn't clear to me. You'd be surprised how much some people will over-engineer some interview questions like that (even when you very explicitly tell them to use the simplest thing possible).
The memcached protocol really is as simple as "CMD [params]", all of which is parsed for you, and this API is just "MULT num1 num2". There are no tricky bits or hidden complexities here as far as I can see.
