This problem is very well designed - it strikes a great balance between algorithmic complexity and logical reasoning. The need to alternate operations based on bit-position and the “power of 2” reductions makes you think carefully about state transitions. I found it particularly interesting how the game essentially boils down to counting zeroes and one flips in the binary representation. For anyone looking for a warm-up or an alternate reflex challenge, I’ve also been playing a browser running game called speed star lately. It’s completely different genre - more about timing your steps and rhythm than binary logic - but it’s a fun way to switch gears after intense problem solving like this