class List<A>
{
    A a = null;
}

class Vektor<A> extends List<A>
{
    A a = null;
}

class Stack<A> extends Vektor<A>
{
    A a = null;
}

class ClassB<A, B, C>
{
    A a = null;
    B b = null;
    C c = null;
}

class ClassA<A, B, C> extends ClassB<C, B, A>
{
    A a = null;
    B b = null;
    C c = null;
}

class Int
{
}

class Bool
{
}

class otth15
{
    void f1( X<A> a )
    {
    }
}