driver.pl : Iteratively call playerA ('X') and player B ('O')
	Usage: perl driver.pl k or just driver.pl k. k is the size of the board and must be less 100. (E.g. perl driver.pl 10)
playerA:
	A random move player which randomly selects an empty grid
playerB:
	It is better than playerA. It randomly selects an empth gird which is adjacent to an non-empty grid
move:
	move is called in driver.pl. which is used to verify whether the outputof  your code is valid 
	move and update "board.txt" if it is valid. move also chech who won the game.
player.c:
	C source code for playerB (and palyer A)
move.c: 
	C source code for move
board.txt:
	the current board