Electron multiplicity plot

Hello dear G4 users, hope you are doing well!
I am using geant4.10.06.p01 root 6.18.04 in ubuntu 19.10. I want to get electron multiplicity plot(frequency vs no of electrons) of geant4 extended electromagnetic example TestEm5 with the file TrackingAction.cc (7.6 KB). While compiling i got an error(see screenshot). Please tell me how can i print out the data from this file(Tracking Action.cc) in geant4 run summary and how can i make electron multiplicity plot from it?
Screenshot from 2020-11-15 16-59-04|690x387