#include <iostream>
using namespace std;
class Derived;
class Base {
static Derived* getDerived();
};
class Derived : public Base {};
int main() {
// your code goes here
return 0;
}
I2luY2x1ZGUgPGlvc3RyZWFtPgp1c2luZyBuYW1lc3BhY2Ugc3RkOwoKY2xhc3MgRGVyaXZlZDsKY2xhc3MgQmFzZSB7CiAgICAgc3RhdGljIERlcml2ZWQqIGdldERlcml2ZWQoKTsKfTsKY2xhc3MgRGVyaXZlZCA6IHB1YmxpYyBCYXNlIHt9OwoKaW50IG1haW4oKSB7CgkvLyB5b3VyIGNvZGUgZ29lcyBoZXJlCglyZXR1cm4gMDsKfQ==