#include <algorithm>
#include <functional>
#include <iostream>

int main()
{
  double arr[] = { 1, 2, 3, 4, 5 };

  std::cout << std::count_if(begin(arr), end(arr), std::bind2nd(std::less<double>(), 3)) << '\n';
  return 0;                                        // x < 3  
}