/* program to compute bearings cost, multiple times
   redone with functions
  October 10, 1997
  CS1711A Class*/

#include <iostream.h>
#include <math.h>

const double HI_CARBON_PRICE = 1.35;     // program constants...
const double LO_CARBON_PRICE = 1.00;     // could be global


void get_input(double& radius, int& number, char& carbon);
// prompted input for call-by-ref paramters

void output(int number_bearings, double radius, char carbon);

double tot_volume(int number_bearings, double radius);
// computes volume of number_bearings spherical bearings of radius radius
// using formula for sphere volume : 4/3*pi*radius-cubed

int main()
{
  int number_bearings;
  double radius, total_volume, volume_of_one;
  char carbon,continu;

  do {  // while continu = Y
	get_input(radius,number_bearings,carbon);
	output(number_bearings,radius, carbon);
	cout << "Input 'Y' to continue, 'N' otherwise";
	cin >> continu;

  }
  while (continu=='Y');
  return 0;

}

void get_input(double& radius, int& number, char& carbon)
   {cout << "Input a decimal number for the radius\n";
	cin >> radius;
	cout << "How many bearings?\n";
	cin >> number;
	cout << "Input carbon: high (h) or low (l)\n";
	cin >> carbon;
   }



void output(int number_bearings, double radius, char carbon)

{	if (carbon=='h'|| carbon=='l') /*valid inputs*/
	 { cout << "The total volume required for " << number_bearings;
	  cout << " bearings of radius " << radius << " is ";
	  cout << tot_volume(number_bearings,radius);

	  // format for 2 decimal output
	  cout.setf(ios::fixed);
	  cout.setf(ios::showpoint);
	  cout.precision(2);

	 {if(carbon=='h')
		cout << endl << "Total cost is $ "
		<< tot_volume(number_bearings,radius)*HI_CARBON_PRICE;
	  else
		 cout << endl << "Total cost is $ "
		 << tot_volume(number_bearings,radius)*LO_CARBON_PRICE;}}
	else  /*traps bad input*/
		 {cout << endl << "Invalid input " << carbon;
		  cout << endl << "Input value must be 'h' or 'l'";}
	cout << endl;

}


double tot_volume(int number_bearings, double radius)
{   const double PI=3.14159;
	double volume_of_one, total_volume;

	volume_of_one = 4.0/3.0*PI*pow(radius,3.0);
	total_volume = number_bearings* volume_of_one;
	return (total_volume);
 }