All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars
 perplexus dot info

 Hat Exchange (Posted on 2005-02-24)
At a party with N people, each person is identified by a unique number between 1 and N. Each person is also wearing a hat with their number on it. They decide to play a game. Each person passes his or her hat to the person with the next highest number (so person 2 gets hat 1, person 3 gets hat 2, and person 1 gets hat N). The game proceeds from there in rounds; on each round, each person may choose to either keep the hat they currently have, or swap hats with exactly one other person.

What is the minimum number of rounds, as a function of N, that it would take for every person to get their own hat back? Note: each person can see their own hat at any time.

 See The Solution Submitted by Avin Rating: 3.0000 (5 votes)

 Subject Author Date re: Better Solution (spoiler) Hugo 2005-02-26 19:12:54 answer(in my eyes) chris 2005-02-26 06:05:05 Better Solution (spoiler) Tristan 2005-02-26 03:01:46 re(3): Solution Avin 2005-02-26 02:51:48 re(2): Solution Hugo 2005-02-25 16:10:44 re: Solution Avin 2005-02-25 13:15:10 Maximum Federico Kereki 2005-02-24 15:34:05 Solution Hugo 2005-02-24 15:21:26

 Search: Search body:
Forums (0)