// ----- Zmienne globalne ----------------------------------------------------

  int kulaX[100],kulaY[100],kulaR,Ilosc;
  int wybrany;


// ----- Form1_Load() ---------------------------------------------------------

  wybrany=-1;
  kulaR=10;
  Ilosc=5;


// ----- pictureBox1_MouseDown() ----------------------------------------------

  if(e->Button==Windows::Forms::MouseButtons::Left)
  {
    for(int w=0; w<Ilosc; w++)
    {
      int px=e->X-kulaX[w];
      int py=e->Y-kulaY[w];
      if(px*px+py*py<=kulaR*kulaR)
        wybrany=w;
    }
  }   


// ----- pictureBox1_MouseMove() ----------------------------------------------

  if(e->Button==Windows::Forms::MouseButtons::Left && wybrany!=-1)
  {
    kulaX[wybrany]=e->X;
    kulaY[wybrany]=e->Y;
    pictureBox1->Invalidate();
  }
  else 
    wybrany=-1;


// ----- pictureBox1_Paint() --------------------------------------------------

 
  Graphics^ grafika = e->Graphics;
  grafika->Clear( Color::White);
    for(int w=0; w<Ilosc; w++)
     grafika->FillEllipse(Brushes::Green, kulaX[w]-kulaR,kulaY[w]-kulaR,2*kulaR,2*kulaR);