int hist2a() {

  TH1F* h = new TH1F("h","h",80,-40,40);
  TRandom r;
  for (int i=0;i<15000;i++) {
    h->Fill(r.Gaus(0,7));
  }
  h->Draw();
  //h->Rebin(2);
  //h->GetXaxis()->SetRangeUser(2, 5);
  //gPad->SetLogy();

 return 0;
}