/in/foo.cc: In member function 'bool poi::insert(int)':
/in/foo.cc:25:53: warning: operation on 'ind' may be undefined [-Wsequence-point]
         while(va[ind].first&&va[ind].second!=num)ind=((++ind)%maxva);
                                                  ~~~^~~~~~~~~~~~~~~~
/in/foo.cc: In member function 'int& poi::get(int)':
/in/foo.cc:32:59: warning: operation on 'ind' may be undefined [-Wsequence-point]
         while(va[ind].first==true&&va[ind].second!=num)ind=((++ind)%maxva);
                                                        ~~~^~~~~~~~~~~~~~~~