Two good tic-tac-toe players started a game, but the wind blew away their paper just after the second play. Given that the situation was as follows, who was to play next, O or X?

       |   |
    ---+---+---
     O |   |
    ---+---+---
     X |   |

If X had played the opposite corner, what would you say?

scenario 1:

If X started, game is easily winable by X (next move middle, then bottom middle). That would mean bad play by O (against assumption). So O started, and is next to play.

scenario 2:

Had either player started in such a way, they were both easily beatable. X start: X to centre, then top left. O start: O to top left, then centre. So impossible to tell who started, but know one is a bad player!

Posted by David on 2004-07-20 01:42:53