// a program stub for debugging of function "unitprice"
// Mikhail Nesterenko
// 10/2/07

#include <iostream>
using namespace std;

// computes price per square inch of a pizza
double unitprice(int diameter, double price);

int main() {

    char again='y';
    do{
      int diameter;
      double price, unitprice_result;
      cout << "Enter pizza price and diameter: ";
      cin  >> price >> diameter;

      unitprice_result = unitprice(diameter, price);
      
      cout << "Unit price for your pizza is: " << unitprice_result << endl;
      cout << "Again? (y/n) ";
      cin >> again;
    }while(again=='y');


}

// Returns the price per square inch of a pizza. 
// "diameter: is the diameter of the pizza in inches.
// "price" is the price of the pizza.
double unitprice(int diameter, double price) {
    const double PI = 3.14159;
    double radius, area;

    radius = diameter/2.0;
    area = PI * radius * radius;
    return (price/area);
}