#include <iostream>

template <typename T>
int get_at (const T&, int);

struct XY {
	int x, y;
};

template <> int get_at(const int(&in)[2], int i) { return in[i]; }
template <> int get_at(const XY& in, int i) { return (i ? in.y : in.x); }

template <typename T>
struct Vec {
	int x() const { return get_at(m_storage_type, 0); }
	int y() const { return get_at(m_storage_type, 1); }

	T m_storage_type;
};

template <typename T>
std::ostream& operator<< (std::ostream& os, const Vec<T>& v) {
	os << '<' << v.x() << ',' << v.y() << '>';
	return os;
}

int main() {
	Vec<int[2]> v1;
	Vec<XY> v2;

	v1.m_storage_type[0] = 1234;
	v1.m_storage_type[1] = 7777;

	v2.m_storage_type.x = 44;
	v2.m_storage_type.y = 9999;

	std::cout << v1 << '\n';
	std::cout << v2 << '\n';

	return 0;
}