Tic-Tac-Toc

Tic-tac-toe is played in a 3x3 board. One player is `x' and the other `o'. Players alternate writing `x' or `o' on a blank square. You win if you can make a row, column or diagonal in your mark.

The grid looks like this to start:

   | |
  -+-+-
   | |
  -+-+-
   | |

The first move might be

   | |
  -+-+-
   |x|
  -+-+-
   | |

Then

  o| |
  -+-+-
   |x|
  -+-+-
   | |

Then

  o| |
  -+-+-
   |x|
  -+-+-
  x| |

Then

  o| |o
  -+-+-
   |x|
  -+-+-
  x| |

The last move was forced, since x would otherwise win on the next move.

Then

  o|x|o
  -+-+-
   |x|
  -+-+-
  x| |

Again, forced. Then

  o|x|o
  -+-+-
   |x|
  -+-+-
  x|o|

etc.