I have 2 friends. We have one candybar and we want to divide it evenly. Unfortunately we don't have any way of accurately measuring and cutting the candybar. Therefore we are looking for a method by which we can fairly divide the candybar. If it was just me and one friend, it would be easy: I would divide ($D$) the candybar as evenly as possible into 2 and then pass ($P$) the candybar to my friend and let them choose ($C$). (Thus, the whole method could be encoded as $DPC$.) What method can I use for the current case? What method can I use for the general case of me and $n-1$ friends? How can I prove that the given method is fair?
Please reply soon. I'm getting hungry.
Also, feel free to retag my question. I didn't find a candybar tag.