Compiler says to loop over reference and not copy - makes sense

Author: AndrewEdmonds11

rooutil/examples/PrintEvents.C

@@ -258,7 +258,7 @@ void PrintEvents(std::string filename) {
     }
 
     // trigger branches
-    for (const auto pair : event.trigNameMap) {
+    for (const auto& pair : event.trigNameMap) {
       std::cout << pair.first << ": " << event.triginfo._triggerArray[pair.second] << std::endl;
     }
 

rooutil/inc/RooUtil.hh

@@ -143,7 +143,7 @@ public:
 
     if(event->trkmcsim) { output_ntuple->Branch("trkmcsim", event->trkmcsim); }
 
-    for (const auto pair : event->trigNameMap) {
+    for (const auto& pair : event->trigNameMap) {
       output_ntuple->Branch(pair.first.c_str(), &event->triginfo._triggerArray[pair.second]);
     }