/in/foo.cc: In function 'int main(int, const char**)':
/in/foo.cc:20:10: warning: variable 'begin' set but not used [-Wunused-but-set-variable]
     auto begin = map.begin();
          ^~~~~
/in/foo.cc:21:10: warning: variable 'end' set but not used [-Wunused-but-set-variable]
     auto end = map.end();
          ^~~