but they cannot communicate with each other (neither talking not hearing) they just see person stand in front of him.
On Thu, Mar 3, 2011 at 11:04 PM, Dave <[email protected]> wrote: > I have a way to save 19. Let each prisoner have his own private > variable C, which he initializes to RED if he sees an odd number of > red hats, or to BLACK if he sees an even number of red hats. The last > man in the row announces his C. Every time someone announces the color > RED, everyone ahead of him flips his C to the other color. In turn, > each remaining man announces his C. > > Dave > > On Mar 3, 2:18 am, freecoder <[email protected]> wrote: > > You are one of 20 prisoners on death row with the execution date set > > for tomorrow. > > > > Your king is a ruthless man who likes to toy with his people's > > miseries. He comes to your cell today and tells you: > > > > “I’m gonna give you prisoners a chance to go free tomorrow. You will > > all stand in a row (queue) before the executioner and we will put a > > hat on your head, either a red or a black one. Of course you will not > > be able to see the color of your own hat; you will only be able to see > > the prisoners in front of you with their hats on; you will not be > > allowed to look back or communicate together in any way (talking, > > touching.....) > > > > (The prisoner in the back will be able to see the 19 prisoners in > > front of him > > The one in front of him will be able to see 18…) > > > > Starting with the last person in the row, the one who can see > > everybody in front of him, he will be asked a simple question: WHAT IS > > THE COLOR OF YOUR HAT? > > > > He will be only allowed to answer “BLACK” or “RED”. If he says > > anything else you will ALL be executed immediately. > > > > If he guesses the right color of the hat on his head he is set free, > > otherwise he is put to death. And we move on to the one in front of > > him and ask him the same question and so on… > > > > Well, good luck tomorrow, HA HA HA HA HA HA!” > > > > Now since you all can communicate freely during the night, can you > > find a way to guarantee the freedom of some prisoners tomorrow? How > > many? > > -- > You received this message because you are subscribed to the Google Groups > "Algorithm Geeks" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/algogeeks?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
