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/*  Solves Project Euler problem 1
    ------------------------------

    If we list all the natural numbers below 10 that are multiples of 3 or 5,
    we get 3, 5, 6 and 9. The sum of these multiples is 23.

    Find the sum of all the multiples of 3 or 5 below 1000.

    James Brotchie - brotchie@gmail.com
*/

#include <iostream>

#include <boost/mpl/or.hpp>
#include <boost/mpl/logical.hpp>
#include <boost/mpl/modulus.hpp>
#include <boost/mpl/arithmetic.hpp>
#include <boost/mpl/int.hpp>
#include <boost/mpl/equal_to.hpp>
#include <boost/mpl/comparison.hpp>
#include <boost/mpl/lambda.hpp>
#include <boost/mpl/apply.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/less.hpp>
#include <boost/mpl/plus.hpp>
#include <boost/mpl/assert.hpp>

using namespace boost::mpl;

#define MAX_NUMBER 1000

typedef or_<
    equal_to<modulus<_1, int_<5>>, int_<0>>,
    equal_to<modulus<_1, int_<3>>, int_<0>>> condition;

template <int current, int sum>
struct euler1 {
    typedef typename apply<condition, int_<current>>::type divisible;
    typedef typename euler1<
        plus<int_<current>, int_<1>>::value,
        if_<divisible,
            plus<int_<sum>, int_<current>>,
            int_<sum>>::type::value
        >::type type;
};

template<int sum>
struct euler1<MAX_NUMBER, sum> {
    typedef int_<sum> type;
};

int main() {
    std::cout << euler1<0, 0>::type::value << std::endl;
    return 0;
}