Problem of the Week 982A Sliding Coin PuzzleStart with the sequence of coins as follows (where you can think of O as TAILS and X as HEADS; there are 14 tails and 15 heads) XOXOXOXOXOXOXOXOXOXOXOXOXOXOX Transform it to XXXXXXXXXXXXXXXOOOOOOOOOOOOOO using moves of the following sort: Take two consecutive coins and move them to the end, or the beginning. A general algorithm for the n/n+1 problem is welcome, perhaps with bounds on the number of moves. Source: Suggested by Steven Tedford, Franklin and Marshall College© Copyright 2003 Stan Wagon. Reproduced with permission. |