{
   TCanvas *c1 = new TCanvas("c1","c1",500,500);
   TView *view = TView::CreateView(1);
   view->SetRange(0,0,0,2,2,2);
   const Int_t n = 500;
   auto r = new TRandom();
   Double_t x, y, z;
   TPolyLine3D *l = new TPolyLine3D(n);
   for (Int_t i=0;i<n;i++) {
      r->Sphere(x, y, z, 1);
      l->SetPoint(i,x+1,y+1,z+1);
   }
   l->Draw();
}