{
ifstream filelist("filelist.txt");
std::string filename,filename1;
TCanvas c1;
TFile histofile("track_hists.root","RECREATE");
TH1F* pttr = new TH1F("pttr","Track pT (GeV)",100,8.0,12.0);
while(!filelist.eof()) {
   filelist >> filename;
   filename1= "rfio:/castor/cern.ch/cms" + filename;
   TFile *f =TFile::Open(filename1.c_str());
   TTree *events = (TTree*)f->Get("Events"); 
   events->GetEntry(); 
   std::vector<reco::Track> trackCollection;
   TBranch *branch = events->GetBranch("recoTracks_ctfWithMaterialTracksP5__Rec.obj");
   branch->SetAddress(&trackCollection);
   for( unsigned int index = 0;
           index < events.GetEntries();
           ++index) {
           branch->GetEntry(index);
            if(trackCollection.size()>0)std::cout << "Event = " << index << " " << trackCollection.size()<<std::endl;
           for ( unsigned int bindex = 0; bindex < trackCollection.size(); ++bindex ) {
               reco::Track* track = (reco::Track*)trackCollection[bindex];
               std::cout << track->pt() << std::endl;
               pttr->Fill(track->pt());
               }
           }
   f->Close();
   pttr->Draw();
 histofile.Write();
   }
 histofile.Close();
}