TemplateProgrammingSample.cpp

#include <iostream>

template <unsigned long N>
struct binary {
  static unsigned const value =
			binary<N/10>::value * 2
			+ N % 10;
};

template <>
struct binary<0> {
	static unsigned const value = 0;
};

int main()
{
	unsigned const two = binary<10>::value;
	unsigned const five = binary<101>::value;

	std::cout
		<< two << std::endl
		<< five << std::endl;
}