operator==,!=(std::allocator)
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   template< class T1, class T2 > bool operator==( const allocator<T1>& lhs, const allocator<T2>& rhs ) throw();  | 
(until C++11) | |
|   template< class T1, class T2 > bool operator==( const allocator<T1>& lhs, const allocator<T2>& rhs ) noexcept;  | 
(since C++11) | |
|   template< class T1, class T2 > bool operator!=( const allocator<T1>& lhs, const allocator<T2>& rhs ) throw();  | 
(until C++11) | |
|   template< class T1, class T2 > bool operator!=( const allocator<T1>& lhs, const allocator<T2>& rhs ) noexcept;  | 
(since C++11) | |
Compares two default allocators. Since default allocators are stateless, two default allocators are always equal.
1) Returns true
2) Returns false
Parameters
| lhs, rhs | - | default allocators to compare | 
Return value
1) true
2) false