Erik Reuter wrote:
>
> On Thu, Feb 13, 2003 at 05:41:26PM -0500, David Hobby wrote:
> > It seems to me that there could be Rs who never
> > "checked in". Couldn't an R keep visiting the room and
> > never see B in the up state? Then they would always do
> > the ELSE clause, S would never get to 22, and they would
> > all stay there indefinitely.
>
> My description of X's strategy wasn't as clear as it could have been. I
> should have explicitly indicated the "loop":
>
> Strategy for X:
>
> Initialize (in X's memory) a signal counter S = 0
>
> LOOP
> IF NOT X's first time in room
> AND state of switch B has changed from where X left it last THEN {
> IF switch B changed from up to down THEN {yell "Shit!"; break;}
> ELSE IF switch B changed from down to up THEN increment S
> }
>
> IF S >= 22 THEN declare "Everyone has visited" [much celebration];
>
> TOGGLE switch B and remember its state;
> END_LOOP
>
I think that's how I read it the first time.
Look, when switch B is down, the warden takes one of the Rs
into the switch room 100 times in a row. That should hold
until the switch is down again. And X keeps toggling B,
so it should be down again pretty soon.
---David
_______________________________________________
http://www.mccmedia.com/mailman/listinfo/brin-l
