nobita | Nobita 是一个基于Koa而诞生的一款框架。 | Application Framework library

I want to get a list of possible and acceptable names that Wikipedia has related to the search term. "Corona" in this case.
When typing this:
print(wikipedia.summary("Corona"))

This is giving an output of:

New to c++. I'm solving questions to understand better.

So, i have to make a program which has a parent class called Person and it has 2 derived classes named Student and Professor. The parent class Person has normal variables - std::string name and int age. The derived class Student has variables int sum, int marks[6] and static int cur_id. The derived class Professor has variables int publications and static int cur_id.

Now both the derived classes have 2 overloaded methods, getdata() - gets input from user and putdata() - prints data.

Also both have a static variable named cur_id which gets incremented when an object gets constructed.

Now the problem comes when i try to initialize the static variables using the below code -