euler1

euler1.cpp

#include <iostream>

constexpr int f( int n, int i )
{
  return n<=0 ? 0 : (n + f(n-i, i));
}


static constexpr int MAX = 1000 - 1;

int main()
{
  constexpr int i3 = MAX - MAX % 3;
  constexpr int i5 = MAX - MAX % 5;

  std::cout << f(i3, 3) + f(i5, 5) << std::endl;

  return 0;
}