Are variables local to a class that are not declared as pointers, created on the heap or stack?

Question

Take the following:

A a;

class B; // No content for brevity

class A
{
public:

    A()
    {
         b.SetTitle("hi");
    }

private:

    B b;

}

int main()
{
    return 0;
}

The question here is if b which is declared inside A is declared on the heap or on the stack.

If on the heap, does this mean it is automatically deleted or must i also delete this too?

Side question:

This is what i was originally doing but thought i was being a bit stupid as i had to keep declaring everything as new everywhere.. if the above is on the stack, i guess it wasn't so stupid right?

A a;

class B; // No content for brevity

class A
{
public:

    A()
    {
         this->b( new B() ); // I don't have C++ 14 :( so i can't do make_unique
         b->SetTitle("hi");
    }

private:

    unique_ptr<B> b;

}

int main()
{
    return 0;
}

Answer 1

It still could be either or even (as Thomas Matthews points out below) in a fixed memory block. In this case you can think of it as "inside of A". If you put A on the heap it's on the heap. If you allocate "A" at the top of a function, say, it's on the stack (but inside of A).

Written like this it is a part of A and its lifetime is tied to A. You only need to worry about managing A.