/in/foo.cc: In function 'bool f(std::__cxx11::string, long long int&, long long int&)':
/in/foo.cc:8:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<k.size();i++)
              ~^~~~~~~~~
/in/foo.cc:13:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^