That's seriously clever use of JRO. I (naively) used the stack like I think most people did, giving me just over 2k cycles to finish. It never even entered my mind to step back through ADD commands with JRO like that. Again, super clever, good job.

This solution is so much faster than mine, I love your use of the JRO command

Ahah, you see, it is not JRO 0, it is JRO UP, where UP is a single input of 0.

I wonder how it can even work : first input on B is 0, 0 is neged (-0), then sent to LEFT, then sent DOWN as an argument for JRO... and JRO 0 loops on itself... this is a broken algorythm.

But...but...only works to 9... oh god how can you tolerate that....

Wow, that's one heck of a JRO version of switch/case.

Okay that is fantastic use of JRO and working around the limited flow control available. I love it.