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        riddles >> hard >> Gods of Gibberland
        
(Message started by: renegade_00 on Jun 19^th, 2004, 8:09pm)

Title: Gods of Gibberland
Post by renegade_00 on Jun 19^th, 2004, 8:09pm

Riddle is as follows ----
There are three omniscient gods sitting in a chamber: GibberKnight, GibberKnave, and GibberKnexus, the gods of the knights, knaves, and knexuses of Gibberland. Knights always answer the truth, knaves always lie, and knexuses always answer the XOR of what the knight and knave would answer.

Unfortunately, the language spoken in Gibberland is so unintelligible that not only do you not know which words correspond to "yes" and "no", but you don't even know what the two words that represent them are! All you know is that there is only one word for each.

With only three questions, determine which god is which.

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XOR is boolean for "One or the other, but not both" Which means given two inputs, only one of them can be true for XOR to return true. If they are both the same value (both true or both false) then XOR returns false.

Note 1: What follows are standard rules that are generally assumed unless otherwise noted. The gods only answer yes/no questions. Each god answers in the single word of their language as appropriate to the question; i.e. each god always gives one of only two possible responses, one affirmative and one negative (e.g. they would always answer "Yes" rather than "That would be true"). Each question asked must be addressed to a single specific god; asking one question to all the gods would constitute three questions. Asking a single god multiple questions is permissible. The question you choose to ask and the god you choose to address may be dynamically chosen based on the answers to previous questions. No self-referential questions (e.g. "is this question true iff ...").

Note 2: Because of possible loop conflicts, you may not ask any questions regarding how a knexus would answer.

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Has anyone seen this riddle before, and do you know the answer??? it's been bugging me for 2 weeks and i'm going to go nuts.

Title: Re: Gods of Gibberland
Post by BNC on Jun 19^th, 2004, 9:34pm

As far as I know, it was created by a member of this forum (Eric Yeh -- who seems to have stopped visiting :'(), and was originally published here (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_hard;action=display;num=1028840975;start=0)

Title: Re: Gods of Gibberland
Post by Icarus on Jul 19^th, 2004, 7:30pm

Eric stops in every so often, usually when a thread he has tagged for notification is posted to. If you were to post to the thread BNC linked to, he might even give a reply.

Out of curiousity, where did you come across the riddle, renegate_00?

Title: Re: Gods of Gibberland
Post by renegade_00 on Jul 19^th, 2004, 7:59pm

i don't remember anymore, it was on a website....

Title: Re: Gods of Gibberland
Post by BNC on Jul 20^th, 2004, 5:54am

A google search found these two sites:

non-English (http://forum.jopwijk.be/viewtopic.php?t=266)

In English (http://www.cool-teens.com/forum/archive/t-29842)