example_1

#include<iostream>
using namespace std;
#include<stdio.h>

template<typename T>
class ID
{
    public:
    ID() : a(0) {}
    T getA() { return a;}
    void setA(T a_) { a = a_; }

    private:
        T a;
};

template<typename T>
class A : public T
{
};

int main()
{
    ID<int> id;

    A<ID<int> > ids;

    printf("%d\n", ids.getA());
    return 0;
}