Question 9653 – Programming

Consider the following class definitions in a hypothetical Object Oriented language that supports inheritance and uses dynamic binding. The language should not be assumed to be either Java or C++, though the syntax is similar.

Class P {
    void f(int i) {
        print(i);
    }
}

Class Q subclass of P {
    void f(int i) {
        print(2*i);
    }
} 

Now consider the following program fragment:

Px = new Q();
Qy = new Q();
Pz = new Q();
x.f(1); ((P)y).f(1); z.f(1); 

Here ((P)y) denotes a typecast of y to P. The output produced by executing the above program fragment will be

Correct Answer: D