import java.util.*;
public class Vaja18 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final float pi = 3.14f;
		System.out.print("Vnesi polmer kroga: ");
		float r = sc.nextFloat();
		System.out.print("Vnesi a pravokotnika: ");
		float a = sc.nextFloat();
		System.out.print("Vnesi b pravokotnika: ");
		float b = sc.nextFloat();
		float obseg_kroga = 2 * pi * r;
		float ploscina_kroga = pi * r * r;
		float ploscina_kvadrata = a * b;
		System.out.println("Obseg kroga: "+obseg_kroga);
		System.out.println("Ploscina kroga: "+ploscina_kroga);
		System.out.println("Ploscina kvadrata: "+ploscina_kvadrata);
	}
}