Question

Which is the correct syntax of defining a pure virtual function?

(a) pure virtual return_type func();

(b) virtual return_type func() pure;

(c) virtual return_type func() = 0;

(d) virtual return_type func();

I got this question at a job interview.

The origin of the question is Abstract Classes in portion Derived Classes, Templates & Exception Handling in C++ of C++

Answer 1

Right answer is (c) virtual return_type func() = 0;

Easiest explanation - virtual return_type function_name(parameters) = 0; where {=0} is called pure specifier.