void labelling(Mat img)
{
    int label = 0;

    Scalar colorLUT[1000] = { 0 };
    Scalar color;
    for (int i = 1; i < 1000; i++)
    {
        Scalar color(rand() & 255, rand() & 255, rand() & 255);
        colorLUT[i] = color;
    }
    colorLUT[0] = Scalar(255, 255, 255); // fundalul va fi alb

    Mat labels = Mat::zeros(img.size(), CV_16SC1);
    Mat dst = Mat::zeros(img.size(), CV_8UC3);

    for (int i = 0; i < img.rows; i++)
        for (int j = 0; j < img.cols; j++)
        {
            if (img.at<uchar>(i, j) == 0 && labels.at<short>(i,j) == 0)
            {
                label++;
                std::queue <Point> que;
                labels.at<short>(i,j)  = label;
                que.push({ i,j });
                while(!que.empty())
                {
                    Point oldest = que.front();
                    uchar neighbors[8];
                    int di[8] = { -1,-1,-1,0,0,1,1 ,1 };
                    int dj[8] = { -1,0,1,-1, 1,-1,0,1};
                    int x = oldest.x;
                    int y = oldest.y;
                    for (int k = 0; k < 8; k++)
                    {
                        int vecin_i = x + di[k];
                        int vecin_j = y + dj[k];
                        if(vecin_i>=0 && vecin_j>=0 && vecin_i<img.rows && vecin_j <img.cols)
                            if (img.at<uchar>(vecin_i,vecin_j) == 0 && labels.at<short>(vecin_i,vecin_j) == 0)
                            {
                                labels.at<short>(vecin_i,vecin_j) = label;
                                que.push(Point(vecin_i,vecin_j));
                            }
                    }
                    que.pop();

                }
            }
        }

    for (int i = 1; i < labels.rows - 1; i++)
        for (int j = 1; j < labels.cols - 1; j++)
        {
            Scalar color = colorLUT[labels.at<short>(i, j)]; // valabil pt. Met. 1 BFS
            dst.at<Vec3b>(i, j)[0] = color[0];
            dst.at<Vec3b>(i, j)[1] = color[1];
            dst.at<Vec3b>(i, j)[2] = color[2];
        }

    imshow("labelled", dst);
    waitKey();

}