std::stack<T,Container>::empty
From cppreference.com
                    
                                        
                    
                    
                                                            
                    
| bool empty() const; | (until C++20) | |
| [[nodiscard]] bool empty() const; | (since C++20) | |
Checks if the underlying container has no elements, i.e. whether c.empty().
Parameters
(none)
Return value
true if the underlying container is empty, false otherwise
Complexity
Constant
See also
| returns the number of elements (public member function) |