/in/foo.cc: In function 'bool judge(std::__cxx11::string)':
/in/foo.cc:8:34: error: 'reverse' was not declared in this scope
  reverse(temp.begin(), temp.end());
                                  ^
/in/foo.cc: In function 'std::__cxx11::string transform(int, int)':
/in/foo.cc:21:28: error: 'reverse' was not declared in this scope
  reverse(s.begin(), s.end());
                            ^