> > The solution, to save George Penny both from further embarrassing himself > and from the pecuniary discomfort of dispensing CRAKKER JACKS to the > hundreds in this group who are quite capable of solving it, is > > Ask either guard which door the OTHER guard would say leads to freedom, > and then exit the opposite door. > > daan
Perhaps this is tougher:
Same scenario but with n doors, k of which are fatal, n-k not. n guards, s of whom always tell the truth, n-s always lie. For a given n, k and s, how many questions are needed to be certain of going through a safe door?