Inheritance: If private is default, why do these two examples not work the same way?

I was working around with inheritance in C++. To my knowledge if you don’t specify, B will always inherit private from A.

So why does this code work:

struct A {};
struct B : A {};

int main(void)
{
    A b = B();
    return 0;
}

But this creates the "A is an inaccessible Base of B" error:

struct A {};
struct B : private A {};

int main(void)
{
    A b = B();
    return 0;
}

I would expect them to be the same?

>Solution :

Private inheritance is the default if the derived class is defined using the word class.

If you create it using struct, then inheritance is public by default.