// total mass of cube and sphere
#include <iostream>
#include <math.h>
using namespace std;

namespace cube
{
  double volume(double l)
  {
    return pow(l, 3.);
  }
  
  double mass(double l, double rho)
  {
    return rho * volume(l); 
  }
}

namespace sphere
{
  double volume(double r)
  {
    const double pi = 3.1416;
    return 4./3. * pi * pow(r, 3.);
  }
  
  double mass(double r, double rho)
  {
    return rho * volume(r); 
  }
}

const double rho=7.87; // density

int main()  
{  
  double mass_sum = cube::mass(1., rho) + sphere::mass(2., rho);
  cout << mass_sum << endl; 
}