#include <iostream>
using namespace std;
 
class F 
{
 
};
class S : public F
{
 
};
 
template<typename X, typename Y>
class check
{
	class F { };
	static F find( ... );
	class T { F f[2]; };
	static T find( Y* );
	public:
		enum { m = sizeof(T) == sizeof(find(static_cast<X*>(0)))};
};
 
template <class Q, class R>
bool checkIf() {
	return check<Q, R>::m;
}
 
int main() {
	check <class F, class S> t (F,S);
	cout<< checkIf<class F, class S>() <<endl;
	return 0;
}

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