int AIMinimaxAgent::findBestMove(bool nodeType, Board  b, int depth)
{
        if((depth == 0))
		return b.evaluateBoard();
	
	Board c;		// temp board

	int best;		// the best so far for this level

	int value;		// the value for each node


	// which node are we looking at?

	switch(nodeType)
	{
		// min node, i.e. human move

		case MINNODE :
		{
			best = 99;
			// for each square

			for(int i=0;i<9;i++)
			{
				// make a copy of the board

				c.copy(b);
				// if this move is legal

				if(c.isLegal(i))
				{
					//make the move

					c.makeMove(X, i);
					
					value = findBestMove(!nodeType, c, depth-1);
					
					// if this move is less than the best at this level

					if(value < best) 
						best = value; // update the best

					
					// unmake the move so the next move can be tested

					c.setSquares(EMPTY, i);
				}
			}
			// return the best score that was found

			return best;
		} break;

		// max node, i.e computer move

		case MAXNODE :
		{
			best = -99;
			// for each square

			for(int i=0;i<9;i++)
			{
				// make a copy of the board

				c.copy(b);
				// if this move is legal

				if(c.isLegal(i))
				{
					// make the move

					c.makeMove(O, i);
					
					// find the best move from this position

					value = findBestMove(!nodeType, c, depth-1);
					
					// if this move is better than the current best for this level

					if(value > best)
						best = value; // update the best score

					// unmake the move so we can test the next move

					c.setSquares(EMPTY, i);
				}
			}
			// return the best score found for this level of recursion

			return best;
		} break;
	}
	return 0;
}

int AIMinimaxAgent::getMove(Board b)
{
	int best;
	int value;
	int theMove;

	for(int i=0;i<9;i++)
	{
		if(b.isLegal(i))
		{
			b.setSquares(EMPTY, i);

			value = findBestMove(MINNODE, b, 6);
			if(value > best)
			{
				best    = value;
				theMove = i;
			}
		}
	}
	
	return theMove;
}
  

  
int Board::evaluateBoard()
{	
	if(isWin())
	{
		switch(winner)
		{
			case HUMAN    : return -1;
			case COMPUTER : return  1;
		}
	}
	
	if(numPieces = 9)
		return 0;
}
  

  const bool MAXNODE = true;const bool MINNODE = false;  

  int AIMinimaxAgent::getMove(Board b){	int best;	int value;	int theMove;	// for each square	for(int i=0;i<9;i++)	{		// if the move is possible		if(b.isLegal(i))		{			// make the move			b.makeMove(O, i);			// and look at the consequences			value = findBestMove(MINNODE, b, 6);			if(value > best)			{				best    = value;				theMove = i;			}			b.setSquares(EMPTY, i);		}	}		return theMove;}