1. How to run the game?
   1). Load the .clp file into CLIPS.
   2). (reset)
   3). (run)
   4). Select the role for the program robot.
   5). In each step input X and Y for yourself.
   6). X means row No. (1..8), Y means column No. (1..8).
   7). The black discs are represented in the board as 'X'; The white ones are represented as 'O'; '-' means empty squares.
   
2. The strategies that the program is using.
    1). Global strategy:
      a) Limit the moves available to the opponent
      b) Corners have the very high priorities
      c) Deny the opponent access to critical squares (e.g., Corners) or poison them
      d) Minimize frontier discs (Flip the interior discs more than to flip outer discs??????????????????)

    2). Openning phase:
      a) Don't grab too many discs in the early stage of the game
      b) Avoid placing on XSquares and CSquares prematurely

    The following strategies could also be used. But I don't implement them for the time reason.
    3). Midgame phase:
      a) Avoid unbalanced edges, otherwise, balance them.
      b) Consider the consequence of initiating edge play. Be careful with CSquares and XSquares
      c) Play into regious with odd number of spaces

    4). Endgame phase:
      a) Count the results of moves (by considering possibilities).