/in/foo.cc: In function 'int main(int, const char**)':
/in/foo.cc:31:18: error: cannot convert 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' to 'const char*' for argument '1' to 'int strcmp(const char*, const char*)'
     if(strcmp(c,d)==0)
                  ^