void Graph::Prim_matrix()
{
    Edge *edg = new Edge[edges];            // posortowana rosnąco wzg wag tablica krawędzi
    Edge *mst = new Edge[vertices-1];       // krawędzie MST
    int mst_i = 0;                          // indeks tablicy mst
    int edg_i = 0,
        vert = first_vert;
    bool *processed = new bool[vertices];   // tablica przetworzonych wierzcholkow
    for (int i = 0; i < vertices; i++)
        processed[i] = false;               // zaden nie jest przetworzony
    processed[vert] = true;                 // tylko pierwszy
    for (int i = 0; i < vertices - 1; i++)
    {
        for (int j = 0; j < vertices; j++)
        {
            if (matrix->tab[vert][j] >= 0 && !processed[j])
            {
                edg[edg_i].first_vert = vert;
                edg[edg_i].second_vert = j;
                edg[edg_i].weight = matrix->tab[vert][j];
                edg[edg_i].processed = false;
                edg_i++;
            }
        }
        //cout << "no:\n";
        //for (int i = 0; i < edges; i++)
        //  if(!edg[i].processed)
        //      cout << edg[i].first_vert << "-" << edg[i].second_vert << ": " << edg[i].weight <<"\n";

        edg->quickSort(edg, 0, edges);
        //cout << "sorted:\n";

        //for (int j = 0; j < edges; j++)
        //  if (!edg[j].processed)
        //      cout << edg[j].first_vert << "-" << edg[j].second_vert << ": " << edg[j].weight << "\n";

        for (int k = 0; k < edges; k++)
        {
            if (!edg[k].processed && !(processed[edg[k].first_vert] && processed[edg[k].second_vert]))
            {
                mst[mst_i] = edg[k];
                edg[k].processed = true;

                vert = edg[k].second_vert;

                processed[edg[k].first_vert] = true;
                processed[edg[k].second_vert] = true;
                mst_i++;
                break;
            }
        }
        //cout << "processed: \n";
        //for (int i = 0; i < vertices - 1; i++)
        //{
        //  printf("%2d|%2d\n",i, processed[i]);
        //}

    }
    cout << "Algorytm Prima - Macierzowo: \n";
    cout << "  EDGE  : WEIGHT\n";
    int sum = 0;
    for (int i = 0; i < vertices - 1; i++)
    {
        printf("(%2d-%-2d) : %2d\n", mst[i].first_vert, mst[i].second_vert, mst[i].weight);
        sum += mst[i].weight;
    }
    cout << "    Sum = " << sum << "\n\n";
    delete[] edg;
    delete[] mst;
    delete[] processed;
};