You get a note from the police station. Unfortunately, it is full of coffee stains.

We have tracked down three suspects for a murder. We know that one of them is guilty and each one of them can be either a knight or a liar. Each one of them wrote a statement or two, but parts of them are full of coffee stains and we are not sure which one of the words in the brackets should be under each coffee stain:

A: ███ (B/C) is innocent. He is also a knight.

B: A is █████ (innocent/guilty). He is also a liar

C: A and B are both ████ (liars/knights)

From these statements, can you figure out who is guilty?

Start first with the comment from B and consider whether that person is a knight or liar.

If B = Knight, then A must be a Liar.  This means that A's comment must be directed at C, since he could not lie that B was a Knight.  This would also mean that C was Guilty since A's claim of C's innocence would be a lie.  And since C is a liar, then his statement is false.  This is confirmed since A and B are not the same.

If B = Liar, then A must be a Knight.  Thus, C must also be a knight.  However, this would make C's statement false since A and B are neither both Liars, nor both Knights.  Therefore, B ≠ Liar.

A = Liar
B = Knight
C = Liar

C is guilty.

Posted by hoodat on 2007-04-10 13:51:42