public class TicTacToe
{
    TicTacToe(int size)
    {
        this.size = size;
        board = new char [size] [size];
        done = false;
        moveCount = 0;
        
        for (int i = 0; i < size; i++)
        {
            for (int j = 0; j < size; j++)
            {
                board[i][j] = EMPTY;
            }
        }
        turn = 'X';
    }
    
    public boolean catsGame()
    {
        return (moveCount == size * size);
    }
    
    public boolean gameWon()
    {
        if (done)
        {
            return true;
        }
        
        for (int i = 0; i < size; i++)
        {
            if (inALine(i, 0, 0, 1))  // row
            {
                return true;
            }
            if (inALine(0, i, 1, 0))  // column
            {
                return true;
            }
        }
        
        if (inALine(0,0,1,1))  // major diagonal
        {
            return true;
        }
        
        if (inALine(0, size-1, 1, -1))  // minor diagonal
        {
            return true;
        }
        
        return false;
    }
    
    private boolean inALine (int startX, int startY, int incX, int incY)
    {
        int x = startX;
        int y = startY;
        char match = board[x][y];
        
        if (match == EMPTY)
        {
            return false;
        }
        
        for (int i = 1; i < size; i++)
        {
            x += incX;
            y += incY;
            if (match != board[x][y])
            {
                return false;
            }
        }       
        return true;
    }
    
    public char getTurn ()
    {
        return turn;
    }
    
    public int getSize()
    {
        return size;
    }
    
    public char getPlay (int x, int y)
    {
        return board[x][y];
    }
    
    public void makeGuess (int x, int y)
    {
        if (board[x][y] == EMPTY)
        {
            moveCount++;
            board[x][y] = turn;
            turn = getOtherTurn ();
        }
    }
    
    public char getOtherTurn ()
    {
        if (turn == 'X')
        {
            return 'O';
        }
        else
        {
            return 'X';
        }
    }
 
    private int moveCount;
    private boolean done;
    private int size;
    private char [] [] board;
    private char turn;
    private static final char EMPTY = 'e';
}