std::chrono::month_day
From cppreference.com
                    
                                        
                    
                    
                                                            
                    | Defined in header  <chrono> | ||
| class month_day; | (since C++20) | |
The class month_day represents a specific day of a specific month, of some yet to be specified year.
month_day is a TriviallyCopyable StandardLayoutType.
Member functions
| constructs a month_day(public member function) | |
| retrieve the stored month and day values (public member function) | |
| checks if the month_dayis valid(public member function) | 
Nonmember functions
| compares two month_dayobjects(function) | |
| outputs a month_dayinto a stream(function template) | |
| outputs a month_dayinto a stream according to the provided format(function template) | |
| parses a month_dayfrom a stream according to the provided format(function template) |