7/9     ~ilyas/pub/hat_problem.txt.
        \_ Don't post a solution URL, please.  If you know the answer, don't
           spoil it for others.
           \_ wtf? how is that ruining it for others? you don't have to go
              there!
        \_ "and must simultaneously guess the colors of their respective hats.
            If the following condition holds, they share a $3 million price:  At
            least one person guesses correctly, and no one guesses incorrectly."
             The first four words quoted above imply that all must guess. the
             "condition" implies that all need not guess.  Which is it?
                \_ Statement of the problem fixed, thank you. -- original poster