In file included from main.cpp:$6$:

CourseGradebook.h: In member function $$virtual std::unordered$\_$map, double$>$ CourseGradebook::GetStudentScores$($int$)$:

CourseGradebook.h:$59$:$68$: error: passing $$const std::unordered$\_$map$$ as $$this$$ argument discards qualifiers $[-$fpermissive$]$

$59|$ studentScores$[$entry$.$first$]=$ entry.second$[$studentID$]$;

$|^$

In file included from $/$usr$/$include$/$c$++/9/$unordered$\_$map:$47,$

from main.cpp:$3$:

$/$usr$/$include$/$c$++/9/$bits$/$unordered$\_$map.h:$985$:$7$: note: in call to $$std::unordered$\_$map$<\_$Key, $\_$Tp$,\_$Hash, $\_$Pred, $\_$Alloc$>$::mapped$\_$type& std::unordered$\_$map$<\_$Key, $\_$Tp$,\_$Hash, $\_$Pred, $\_$Alloc$>$::operator$[]($const key$\_$type&$)[$with $\_$Key $=$ int; $\_$Tp $=$ double; $\_$Hash $=$ std::hash; $\_$Pred $=$ std::equal$\_$to; $\_$Alloc $=$ std::allocator $>$; std::unordered$\_$map$<\_$Key, $\_$Tp$,\_$Hash, $\_$Pred, $\_$Alloc$>$::mapped$\_$type $=$ double; std::unordered$\_$map$<\_$Key, $\_$Tp$,\_$Hash, $\_$Pred, $\_$Alloc$>$::key$\_$type $=$ int$]$

$985|$ operator$[]($const key$\_$type& $\_\_$k$)$