/in/foo.cc: In function 'int main()':
/in/foo.cc:26:12: error: 'yes' was not declared in this scope
   26 |    cout << yes << endl;
      |            ^~~
/in/foo.cc:29:12: error: 'no' was not declared in this scope
   29 |    cout << no << endl;
      |            ^~
/in/foo.cc: In function 'bool isequal(std::string, std::string)':
/in/foo.cc:19:1: warning: control reaches end of non-void function [-Wreturn-type]
   19 | }
      | ^