Linked list of different classes

[AleaIactaEst]

I need some way to declare a linked list (or vector) where each element may be of any class.
Unfortunately this seems to be impossible with the standart containers, because all elements in a std::list or std::vector have to be of the same type.

My basic idea to achive this was using polymorphism:

class ElementBase {};    //Empty base class

class Scalar_Float : public ElementBase {
    public:
        float val;
};

class Scalar_Int : public ElementBase {
    public:
        int val;
};

std::list<ElementBase*> LL;

Like this i can add elements of arbitrary classes to the linked list, but i just can't figure out how to read the contents of the linked list.

I could add a pure virtual function to the ElementBase class to retrieve the value(s) stored in the derived classes, but i can't provide a type for the return value, because the type of "val" is always different.

Any idea to solve this problem is welcome :)