@Override
	public boolean equals( Object o )
	{
		if (o instanceof NPuzzleHash)
		{
			NPuzzleHash h = (NPuzzleHash)o;
			for (int y = 0; y < board.length; y++)
			{
				for (int x = 0; x < board[y].length; x++)
				{
					if (board[y][x] != h.board[y][x])
					{
						return false;
					}
				}
			}
			return true;
		}
		return false;
	}