template <class Range>
ValueTypeOf<Range> ASum(const Range& rng, const ValueTypeOf<Range>& zero)
{
	int n = rng.GetCount();
	if(n == 1)
		return rng[0];
	if(n == 0)
		return 0;
	auto l = Async([&] { return ASum(SubRange(rng, 0, n / 2)); });
	auto r = Async([&] { return ASum(SubRange(rng, n / 2, n - n / 2)); });
	while(!l.IsFinished() || !r.IsFinished())
		Sleep(1);
	return l.Get() + r.Get();
}