std::pair<iterator,bool> insert( const value_type& value );   (1)   (since C++11)   std::pair<iterator,bool> insert( value_type&& value );   (2)   (since C++11)   iterator insert( const_iterator hint, const value_type& value );   (3)   (since C++11)   iterator insert( const_iterator hint, value_type&& value );   (4)   (since C++11)   template< class InputIt >
void insert( InputIt first, InputIt last );   (5)   (since C++11)   void insert( std::initiali