| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 358.1 | Hope the Hint Isn't Too Broad | PROSE::WAJENBERG | | Thu Jul 24 1986 13:50 | 6 |
| Ask one guard what the other would say.
Work it out from there. Consider what the lying guard would say,
then what the true guard would say.
Earl Wajenberg
|
| 358.2 | Yes, Captain Kirk, it all very logical... | WIND::WAY | I don't think we're in Kansas anymore | Thu Jul 24 1986 18:10 | 14 |
| That helps....
If I have it correctly, (and it's been a while since I've fooled
with any brain teasers so I'm rusty) it's like this.
Let's say door 1 is to the castle, and door 2 is certain death.
If the lying guard was asked what the other guard would say, his
answer would be door 2. The true guard would know the other guard
would lie and also anwer 2, so you know 1 is the okay door.
Wow, now I can go see the movie!
Thnx,
Frank
|
| 358.3 | The puzzle was not set up correctly | ULTRA::HERBISON | B.J. [Digital Internal Use Only] | Sun Aug 03 1986 21:29 | 30 |
| There is a problem with the puzzle that is asked in Labyrinth.
(This should probably go where the puzzle was first brought
up, but I must have just set that note unseen in an attempt
to get up to date with this file.)
There are four guards. The bottom two do not know which
door is which, but they say that the top two guards do know
the which door is which. When the top guards are asked,
one of the *top* guards says `one of us always lies and the
other always tells the truth'.
There are two cases:
The guard that said `one guard is a liar' was telling
the truth. In this case, just ask the guard which
way to go---he must be the truth teller.
The guard that said `one guard is a liar' was lying.
Then we don't know that one guard always lies and
that the other always tells the truth. In this case
we can not solve the problem.
So either the solution is easy, or we can't solve it. The
fancy question that they used in the movie is either unnecessary
or not guaranteed to work.
The solution: Have one of the *bottom* guards say that one
of the top guards lies and that the other tells the truth.
B.J.
|
| 358.4 | analysis is useless | KALKIN::BUTENHOF | Approachable Systems | Mon Aug 04 1986 12:59 | 18 |
| That's no solution unless we know that the bottom guards
tell the truth.
The puzzle is a nice logical problem, but not very practical
in real life: at the very least you must accept as fact that
one participant in fact *always* lies and that the other
*always* tells the truth and nothing but the truth.
In a situation where I had reason to believe that one (or
possibly *both*) of two doors led to death, I wouldn't exactly
jump at the chance to trust my life to two strangers obviously
in the employ of the nasty person who owns the castle and
does not wish me to reach its center...
Face it: this is fantasy. Don't question too much: you just
ruin the story.
/dave
|