// Marvyn De La Torre    CS1A    Chapter 3, P.147, #18

/*************************************************************
// Calculate Pizza Slices
//
// This program displays the number of slices that can be made
// from a pizza based on its diameter.
//
// Input:
// Pizza diameter
//
// Output:
// Number of pizza slices
*************************************************************/

#include <iostream>
#include <iomanip>
using namespace std;

int main()
{
    double diameter;
    double radius;
    double area;
    double slices;
    const double PI = 3.14159;

    cin >> diameter;

    radius = diameter / 2;
    area = PI * radius * radius;
    slices = area / 14.125;

    cout << fixed << showpoint << setprecision(1);
    cout << "The pizza can be divided into " << slices << " slices.";

    return 0;
}