C++ static function

Question

As i know, in c++ we can call static function only this way: ClassName::FunctionName(); So why does this code work?
https://code.sololearn.com/c1zFZSM0KxMg/?ref=app

Answer 1

is it something new?

Answer 2

Static members and methods of a class are shared among all of it's instances.

Calling a static method using scope operator relieves you from instantiating an object of the class itself.

Answer 3

Anna Simonyan no, I suppose not. Definitely, not a new feature from modern C++.