diff --git a/examples/AnalysisROOT.cc b/examples/AnalysisROOT.cc
index 648925a..2419823 100644
--- a/examples/AnalysisROOT.cc
+++ b/examples/AnalysisROOT.cc
@@ -1,111 +1,112 @@
 //! Simple HEJ analysis to plot Delta y_{fb} with ROOT
 
 #include <memory>     // for std::unique_ptr
 #include <iostream>   // for std::cout
+#include <stdexcept>
 
 #include "TFile.h"
 #include "TKey.h"
 #include "TH1.h"
 
 #include "HEJ/Analysis.hh"
 #include "HEJ/Event.hh"
 #include "HEJ/Version.hh"
 
 namespace YAML {
   class Node;
 }
 
 namespace LHEF {
   class HEPRUP;
 }
 namespace {
   void Fill2DHistogram(TH1D & h,double x,double wt)
   {
     const int binnumber=h.GetXaxis()->FindBin(x);
     const double binwidth=h.GetXaxis()->GetBinWidth(binnumber);
     h.Fill(x,wt/binwidth);
   }
 
   class AnalysisROOT: public HEJ::Analysis {
   private:
     TFile hfile_;
     TH1D htotal_,hydif_,hyf_,hyb_;
   public:
     AnalysisROOT(
       YAML::Node const & /* config */, LHEF::HEPRUP const & /* heprup */
     ):hfile_{"HEJ.root","RECREATE",
              ("Output from "+HEJ::Version::package_name_full()).c_str()},
       htotal_{"total","total",1,-0.5,.5},
       hydif_{"ydif","ydif",40,0.,10.},
       hyf_{"yf","yf",40,-5.,5.},
       hyb_{"yb","yb",40,-5.,5.}
     {
       // Setup histograms
       htotal_.Sumw2();
       hydif_.Sumw2();
       hyf_.Sumw2();
       hyb_.Sumw2();
     }
 
     void fill(
       HEJ::Event const & event,
       HEJ::Event const & /* FO_event */
     ) override {
       const double weight=event.central().weight;
       htotal_.Fill(0.0,weight);
       auto const & jets=event.jets(); // jets are sorted in rapidity
       Fill2DHistogram(hydif_,
           fabs(jets.back().rapidity()-jets.front().rapidity()), weight);
       Fill2DHistogram(hyf_, jets.front().rapidity(), weight);
       Fill2DHistogram(hyb_, jets.back().rapidity(), weight);
     }
 
     bool pass_cuts(
       HEJ::Event const & event,
       HEJ::Event const & /* FO_event */
     ) override {
       if (event.jets().size()<2)
         return false;
       return true;
     }
 
     void scale(const double xsscale) override {
-      std::cout << "AnalysisROOT scales the histograms" << std::endl;
+      std::cout << "AnalysisROOT scales the histograms\n";
 
       TList* list = hfile_.GetListOfKeys() ;
-      if (!list) { printf("<E> No keys defined \n") ; exit(1) ; }
+      if(!list) throw std::logic_error{"<E> No keys defined\n"};
       TIter next(list) ;
       TKey* key ;
       TObject* obj ;
 
       while ( (key = (TKey*)next()) ) {
         obj = key->ReadObj() ;
         auto hist = dynamic_cast<TH1*>(obj);
         if(hist) {
           std::cerr << "Histo name: " << hist->GetName()
                     << " title: " << hist->GetTitle()
                     << "will be scaled\n";
           hist->Scale(xsscale);
         } else {
            std::cerr << "<W> Object " << obj->GetName()
                      << " is not 1D or 2D histogram : will not be scaled\n";
         }
       }
     }
 
     void finalise() override {
       hfile_.Write();
       hfile_.Close();
-      std::cout << "AnalysisROOT bids you farewell " << std::endl; // be polite
+      std::cout << "AnalysisROOT bids you farewell\n"; // be polite
     }
 
   };
 }
 
 extern "C"
 __attribute__((visibility("default")))
 std::unique_ptr<HEJ::Analysis> make_analysis(
     YAML::Node const & config, LHEF::HEPRUP const & heprup
 ){
   return std::make_unique<AnalysisROOT>(config, heprup);
 }