// -----------------------------------------------------
// System Headers
// -----------------------------------------------------

#include <iostream>
#include <vector>

// -----------------------------------------------------
// Using Directives
// -----------------------------------------------------

using std::vector;

// -----------------------------------------------------
// setValues - Set 'values[current]' to false and then
//             continue onward recursively (moving
//             'current' forward by 'step' each time)
//             until 'values' has been exhausted
// -----------------------------------------------------

static void setValues(vector<bool> &values, unsigned step, unsigned current)
{
   if(current < values.size())
   {
      values[current] = false;
      setValues(values, current + step, step);
   }
}

// -----------------------------------------------------
// showValues - If 'values[number]' is true, display
//              'number' then call setValues to nullify
//              all multiples of 'number' and then
//              'showValues' again recursively until
//              'values' has been exhausted
// -----------------------------------------------------

static void showValues(std::vector<bool> &values, unsigned number = 2)
{
   if(values[number])
      std::cout << number << "\n";

   setValues(values, number, 2 * number);

   if(++number < values.size())
      showValues(values, number);
}

// -----------------------------------------------------
// main
// -----------------------------------------------------

int main()
{
   // -----------------------------------------------------
   // Show all primes up to 'N' without using any loops,
   // division or modulus operations
   // -----------------------------------------------------

   static const int N = 1000;

   vector<bool> values(N, true);
   showValues(values);

   return(0);
}