Which Function will get called first?

If depends on the declaration of the function and how you call the function.

Let BaseClass be the base class and DerivedClass is the derived class.

Then in the main function:

BaseClass b;
DerivedClass d;

b.f(); // Calls base class f().
d.f(); // Calls derived class f().

Now if function f() is declared virtual in the base class then:

BaseClass b;
DerivedClass d;

b.f(); // Calls base class f().
d.f(); // Calls derived class f().

BaseClass* bp;

bp = &b;
bp->f() // Call base class f().

bp = &d;
bp->f(); // Calls derived class f().

This is basic c++ and any book should give you this information.

-Saurabh