Thursday, March 21, 2013

The Hardest Riddle Ever

 A man is on the fine line between genius and insane. His inventions and cures have saved the lives of millions yet he has committed horrible crimes. The king has no idea what to do with him, so he lets the man make his own choice with a twist. 

 The king summons the genius to his castle, and when he arrives he finds three IDENTICAL knights standing before him. One of grey, one of gold, and one of black. The king explains that the man will choose a single knight to decide his fate. If he chose the golden knight he will be set free. If he chose the grey knight he will be put in a dungeon for the rest of his life. If he chose the black knight he will be executed. 

 The golden knight only told truth, the grey knight randomly told truth and lies, and the black knight only told lies. All knights only answered yes or no but they spoke ra and ja. The man did not know which meant which. The king finally explained that the man could only ask three question. Without batting an eye the man asked the three questions and walked out happy and free. What did he ask? 

Edit: The man can only ask the question to one particular knight. Also he can ask 1 knight 3 question if he wanted to, he doesn't have to ask one each. The king does not choose the knight!



I am waiting for your answers.


6 comments:

  1. It's important to know if the grey knight answers at random or randomly chooses to answer each query as a liar or as a truth-teller.

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  2. consider his answer random ra or ja

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  3. Well, just choose the golden one. He knows that that one will set him free...

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  4. Well, just choose the golden one. He knows that that one will set him free...

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  5. how to choose the golden one!!!

    you dont know who is the golden one!!!

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  6. Ok, here is my solution to this (very difficult) puzzle:

    Let’s we assume that the three knights are in the following positions:
    position L (left), position C (center), position R (right). They are near each other and they are looking at me.

    Let’s search for he Grey knight (the real problem of the puzzle):

    1st question (to L): Asking the following question to one knight (if they are both, the first of them in the order C and then R) at your left (my right) that isn’t the Gray one: “Is the knight in R the Gray one?”, then you will report me “ra”?

    Scenario 1: if “ra”-->The knight in C is not the Gray one (3 cases-->idem).
    Scenario 2: if “ja”-->The knight in R is not the Gray one (3 cases-->idem).

    2nd question (Scenario 1: to C, Scenario 2: to R): Asking to the knight which isn’t the Grey one AND that isn’t yourself: “Is L the Grey knight?”, then you will report me “ra”?

    Scenario 1-->if “ra”-->The knight in R is the Gray one.
    Scenario 1-->if “ja”-->The knight in L is the Gray one.
    Scenario 2-->if “ra”-->The knight in R is the Gray one.
    Scenario 2-->if “ja”-->The knight in C is the Gray one.

    3rd question (to the other knight which isn’t the Gray one nor the knight of the second question): “Is this my third and last question?” (the man and the knight knows that it is true).

    Scenario A: if “ra”-->The knight who has answered is the Gold one (the man must choose him and he will gain freedom).
    Scenario B: if “ja”->The knight who answered is the Black one (the man must choose the other knight which is not the Gray one nor him).

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