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        riddles >> hard >> Single-file hat excecution - Variation
        
(Message started by: dburton on Jan 1^st, 2009, 5:12pm)

Title: Single-file hat excecution - Variation
Post by dburton on Jan 1^st, 2009, 5:12pm

I have a variation on the Single-file hat excecution. There are 4 men buried up to their shoulders ans can not move the first two are facing opposite sides of a brick wall and can see nothing. The last two are arranged in single file behind one of the men facing the wall. Let's say the man facing the brick wall from the south is a. The man facing the wall from the north is b. c is directly behind him and d is directly behind c. They are each wearing a hat. a and c are black and b and d are white. One of them has to shout out his hat color within 10 minutes or they will all be shot

Title: Re: Single-file hat excecution - Variation
Post by Grimbal on Jan 1^st, 2009, 5:20pm

Do they know the colors of the 4 hats (regardless of where they are)?

Title: Re: Single-file hat excecution - Variation
Post by dburton on Jan 1^st, 2009, 6:24pm

They know there are 4 hats - 2 black and 2 white. They do not know what color their hat is.

Title: Re: Single-file hat excecution - Variation
Post by Eigenray on Jan 1^st, 2009, 10:31pm

In that case: [hide]If d sees two hats of the same color then he knows his own must be the opposite. Otherwise c will realize that his must be the opposite of b.[/hide]

Title: Re: Single-file hat excecution - Variation
Post by Hippo on Jan 2^nd, 2009, 4:51am

I wonder what they will do remaining 590 seconds.