HHC 2015 RPN programming Contest is now open

[Allen]

(09-28-2015 02:12 AM)Egan Ford Wrote:  Too bad we could not use the CX, e.g. X<>F would have been very handy. My first thought on solving this was to or the bits, then and with 3 different masks and check for 15, 30, or 60.

That's mostly what my 64 byte attempt was but with base-10.

I agree! Even with an AND function, one can check for one of the following numbers (binary) [63,62,61,60,47,31,30,15] with out much trouble. x AND x/2 AND x/4 AND x/8.
If the result is >0 then x was one of those numbers.