this function checks if there are any unvisited nodes . concode_field_sep List<NetNode<T>> _marked_nodes concode_elem_sep NetNode<T> _start_node concode_elem_sep Queue<NetNode<T>> _queue concode_elem_sep NetNode<T> _current_node concode_field_sep NetNode<T> next concode_elem_sep Iterator<NetNode<T>> iterator concode_elem_sep void remove
boolean function ( ) { return ! _queue . isEmpty ( ) ; }