private static void TryHorizontalLines(PictureDescription descriptor, Solution solution, ref Command? bestCommand, ref int bestScore)
        {
            for (int y = 0; y < descriptor.NumRows; ++y)
            {
                for (int x = 0; x < descriptor.NumCols;)
                {
                    int startX = x;
                    int endX = x;
                    bool skipped = false;
                    int score = 0;
                    
                    for (;;)
                    {
                        if (x >= descriptor.NumCols)
                        {
                            break;
                        }
                        if (descriptor.IsFilled(x, y))
                        {
                            if (!solution.IsFilled(x, y))
                            {
                                ++score;
                                endX = x;
                            }
                        } else if (skipped)
                        {
                            skipped = true;
                        } else
                        {
                            ++x;
                            break;
                        }

                        ++x;
                    }

                    int len = endX - startX + 1;

                    if (len > 0)
                    {
                        if (score > 0 && score > bestScore)
                        {
                            var command = solution.MakeHorizontalLine(startX, y, len);

                            if (score > bestScore)
                            {
                                bestCommand = command;
                                bestScore = score;
                            }
                        }
                    }
                }
            }
        }
 public void AddCommand(Command command)
 {
     commands.Add(command);
 }