SeungHyun Jeon FuZer

## gist:2d7dc665572f1238737f9e5fa70d99df
#include <iostream>

template <std::size_t Idx>
struct A {
    constexpr static std::size_t idx = Idx;

    template <std::size_t Target>
    using get = std::enable_if_t<(Idx > Target), std::conditional_t<Target == 0, A<Idx>, A<Idx-Target>>>;
};

## gist:8681b5be993963e19063b84e8a47a9b6
#include <iostream>

template <std::size_t Idx>
struct A {
    constexpr static std::size_t idx = Idx;

    template <std::size_t Target>
    using get = std::conditional_t<Target == 0, A<Idx>, typename A<idx-1>::template get<Target-1>>;
};
	#include <iostream>

	template <std::size_t Idx>
	struct A {
	constexpr static std::size_t idx = Idx;

	template <std::size_t Target>
	using get = std::enable_if_t<(Idx > Target), std::conditional_t<Target == 0, A<Idx>, A<Idx-Target>>>;
	};