Ever want to just be able to write `512 K` instead of `512 * 1024` or `524288` in code? Well, wish no more.

power-literals.cpp

#include <iostream>
#include <limits>
#include <stdexcept>
#include <exception>
using namespace std;

static const unsigned long long int max_ull
	= std::numeric_limits<unsigned long long int>::max();

constexpr unsigned long long int
operator""_K(unsigned long long int value)
{
	return (value > max_ull / 1024)
		? throw std::range_error("value out of range")
		: (value * 1024);
}

constexpr unsigned long long int
operator""_M(unsigned long long int value)
{
	return (value > max_ull / (1024 * 1024))
		? throw std::range_error("value out of range")
		: (value * 1024 * 1024);
}

constexpr unsigned long long int
operator""_G(unsigned long long int value)
{
	return (value > max_ull / (1024 * 1024 * 1024))
		? throw std::range_error("value out of range")
		: (value * 1024 * 1024 * 1024);
}

constexpr unsigned long long int
operator""_T(unsigned long long int value)
{
	return (value > max_ull / (1024ull * 1024 * 1024 * 1024))
		? throw std::range_error("value out of range")
		: (value * 1024 * 1024 * 1024 * 1024);
}

int main() {
	std::cout << 512_K << "\n";     // 524288
	std::cout << 1_M << "\n";       // 1048576
	std::cout << 1_G << "\n";       // 1073741824
	std::cout << 1_T << "\n";       // 1099511627776
	return 0;
}