private void button1_Click(object sender, EventArgs e)
    {
        Knapsack();
    }
    private void Knapsack()
    {
        List<Plecak> descendingKanps = _plecakList.OrderByDescending(o => o.W).ToList();
        List<Produkt> descendingProducts = _produktList.OrderByDescending(o => o.cena).ToList();
        int N = descendingProducts.Count;
        double maxVal = 0;
        List<Produkt> addedProducts = new List<Produkt>();
        foreach (Plecak p in descendingKanps)
        {

            double[,] V = new double[N + 1, (int)p.W + 1];
            for (int c = 0; c <= p.W; c++)
            {
                V[0, c] = 0;
            }
            for (int r = 0; r <= N; r++)
            {
                V[r, 0] = 0;
            }
            for (int pos = N - 1; pos >= 0; pos--)
            {

                for (int i = 1; i <= N; i++)
                {
                    for (int wt = 1; wt <= p.W; wt++)
                    {

                        if (descendingProducts[i - 1].waga < wt + 1)
                        {
                            V[i, wt] = Math.Max(descendingProducts[i - 1].cena + V[i - 1, wt - descendingProducts[i - 1].waga], V[i - 1, wt]);
                        }
                        else
                            V[i, wt] = V[i - 1, wt];


                        maxVal = V[i, wt];
                    }

                }

            }
            summary.Items.Add("maximum val for knapsack: " + p.nazwa + " is: " + maxVal);
        }

    }