#include <stdio.h>

class Base {
  public:
    Base() {
        method();
    }
    virtual void method(void) = 0;
};

class Derived : public Base {
  public:
    Derived() { }
    void method(void) {
        printf("derived\n");
    }
};

int main() {
    Derived d();
    return 0;
}