void Read_Files()
{

  gROOT->Reset();

  gROOT->ProcessLine(".L Track.cxx+");
  gROOT->ProcessLine(".L Event.cxx+");

  // loop over root files
  Char_t InputFile[200];
  Int_t nFiles = 20;
  Int_t iEvent_nocut = 0;

  for(Int_t iFile = 1; iFile<=nFiles; iFile++)
    {

      sprintf(InputFile ,"pp_14TeV_%i.root",iFile);
      TFile *fTreeFile  = new TFile(InputFile);
      TTree *treeEvents = (TTree *) fTreeFile->Get("LHC");
      Event *event      = new Event();
      treeEvents->SetBranchAddress("LHC",&event);

      printf(" Open file \n%s\n",InputFile);

      for(Int_t iEvent =0; iEvent < treeEvents->GetEntries(); iEvent++)
	{

	  treeEvents->GetEntry(iEvent);

	  if(!(iEvent_nocut % 100 && (iEvent_nocut)))
	    {
	      printf("Processed Events: %i\n",iEvent_nocut);	    
	    }

 	  iEvent_nocut++;


	}
    }

  printf("---------------------\n");
  printf("No. of Events          = %f\n",iEvent_nocut);
  printf("---------------------\n");

}