#include <iostream>

using namespace std;
#define PI 3.14159265

int main()
{
	float r, d, c, a;

	cout << "Radius: ";
	cin >> r;

	d = 2 * r;
	c = 2 * PI * r;
	a = PI * r * r;

	cout << "Diameter = " << d << endl;
	cout << "Circumference = " << c << endl;
	cout << "Area = " << a << endl;

	return 0;
}