Determine the greater of two values without using comparison operators.

get_max.cpp

template<typename T>
constexpr bool is_positive(const T& value)
{
	return ! (value & 1 << (sizeof(T) * 8 - 1));
}

template<bool condition>
struct determine;

template<>
struct determine<true>
{
	template<typename T>
	const T& operator()(const T& first, const T& second) const
	{
		return first;
	}
};

template<>
struct determine<false>
{
	template<typename T>
	const T& operator()(const T& first, const T& second) const
	{
		return second;
	}
};

int main(int argc, char* argv[])
{
	constexpr int first = -4;
	constexpr int second = -5;
	
	constexpr int result = first - second;
	
	auto max = determine<is_positive(result)>()(first, second);
	
	print::ln(max);
}