First guy is a coin toss - let's wish him good luck. His job is to establish the parity of black hats visible to him. He says "Black" if he sees an odd number of black hats; "Red" otherwise. By paying attention to what has been said, each prisoner will know his hat's color.
*Example:* Second to speak hears "Black" and sees an even number of black hats. He knows his hat is black [odd changed to even - must be his is black] and says "black". Third guy has heard "black" and "black" and sees an even number of black hats. He knows his hat is red [even stayed even - his hat can't be black] and says "red". And so on, to the front of the line. *General algorithm:* The first time you hear "black", say to yourself "odd". Each time your hear "black" after that, change the parity: "even", "odd", ... etc. When it's your turn, if the black hats you see match the running parity, you're Red; Black otherwise. Call out your color. On Fri, Mar 4, 2011 at 7:51 PM, rajul jain <[email protected]> wrote: > > they only hear the answer given by prisoner > > On Fri, Mar 4, 2011 at 6:43 PM, rajul jain <[email protected]> wrote: > >> they can see persons in front of them. >> >> >> On Fri, Mar 4, 2011 at 6:42 PM, rajul jain <[email protected]>wrote: >> >>> @vipin if thay can hear then then what would be the purpose of this >>> question >>> then last person just sacrifice himself and just tell the color of hat of >>> person standing in front of him >>> dont give this type of comments >>> keep in mind "No communication" rule in this question >>> On Fri, Mar 4, 2011 at 5:53 PM, Vipin Agrawal >>> <[email protected]>wrote: >>> >>>> If they cant hear than what the point to create strategy ? >>>> >>>> On Mar 4, 2:40 pm, Tushar Bindal <[email protected]> wrote: >>>> > can't they hear what the previous person has just said? >>>> >>>> -- >>>> 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.
