[Solved] Why is this pure virtual method not compiling? [closed]

Your function is pure virtual, which means the method is virtual and not even implemented in the base class (= 0).
So you have to delete the block after it.

It has to be:

virtual price(int Uchrg, int no_of_unt) = 0;

without the { }.

Virtual means, that classes that inherit from a base class can override the method and called via the base class interface. If a class has a pure virtual method, the class is abstract and this function needs to be overridden by classes that inherit from that base class to be instantiated.

In short:

Virtual:

virtual price(int Uchrg, int no_of_unt)
{
   // Implementation
}

Has an implementation is the base class. Sub classes does not need to override, but they can. The class is not abstract and can be instanciated.

Pure virtual:

virtual price(int Uchrg, int no_of_unt) = 0; // No implementation

There is no implementation, the sub classes must override this to be not abstract.

Call a virtual method via base class:

Base* pBase = new Derived;
pBase->fun();

The method is called via the interface of the base class, but it will be the derived class’ method.