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STL container type as template parameter

I want to create a generic class template that uses an internal concrete container to define different types. Something like that:

#include <vector>
#include <list>
template< typename F, template< class ... > class container_type = std::vector >
struct C
{
    C();
    template< typename U >
    C(container_type< U >);
    C(container_type< F >);
    C(container_type< int >);
    container_type< double > param;
};
C< unsigned, std::list > c;

What is the most natural way to do this? Let's say you want to mention the presence of a container dispenser in any form?

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something like that?

template< typename F, template<class T, class = std::allocator<T> > class container_type = std::vector >
struct C
{
    C() {}
    template< typename U >
    C(container_type< U >) {}
    C(container_type< F >) {}
    C(container_type< int >) {}

    container_type< double > param;
};

C< unsigned, std::list > c;

EDIT:

A similar but slightly simpler approach is used std::queuethat is parameterized by the type of container that will be used internally. I hope this proves that this approach is quite natural. The sample above was tested in VC ++ 10 and shows how to handle the dispenser.

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