Discuss what are static data members in class and how these are defined? How static functions are accessed?

Static data members in a class are those members that are common to all objects of that class. They are not tied to any specific object of the class and hence, they share the same value for all objects. This means if the value of a static data member is changed in one object, the change is reflected in all other objects as well.

To define a static data member in a class, you use the 'static' keyword. Here is an example in C++:

class MyClass {
public:
    static int myStaticVar;
};

In this example, 'myStaticVar' is a static data member of 'MyClass'. Note that you must also define the static member outside of the class, in the global scope:

int MyClass::myStaticVar = 0;

Static functions, on the other hand, can be accessed directly by the class name, without needing to instantiate an object of the class. Like static data members, they are not tied to any specific object of the class.

To define a static function, you also use the 'static' keyword. Here is an example:

class MyClass {
public:
    static void myStaticFunction() {
        // function code
    }
};

In this example, 'myStaticFunction' is a static function of 'MyClass'. You can call this function as follows:

MyClass::myStaticFunction();

In this case, you're calling 'myStaticFunction' directly on the 'MyClass' class, without creating an object of 'MyClass'.