import java.util.Scanner;

public class ExactRegularPolygon {

	public static void main ( String [] args ) {
	
	Scanner input = new Scanner (System.in);
	double n = 0d;
	double s = 0d, perimeter = 0d, r = 0d;
	double R = 0d;
	double circumarea = 0d, inscrarea = 0d, area = 0d;
	String ni, si;

	System.out.println("How many sides on this polygon?");
	ni = new String( input.next() );
	n = Double.parseDouble(ni);
	
	System.out.println("And how long are the sides?");
	si = new String( input.next() );
	s = Double.parseDouble(si);
	

	perimeter = n * s;
	R = s / (2 * (Math.sin(Math.PI/n)));
 	r = R * Math.cos (Math.PI/n);
	area = ( perimeter * r ) / 2;
	inscrarea = Math.PI * r * r;
	circumarea = Math.PI * R * R;
	}
		
public static void printState () {
	System.out.println ("Polygon Sides: " + n);
	System.out.println ("Length of Sides: " + s);
	System.out.println ("Polygon Perimeter: " + perimeter);
	System.out.println ("Circumscribed circle Radius : " + R);
	System.out.println ("Inscribed circle Radius: " + r);
	System.out.println ("Polygon Area: " + area);
	System.out.println ("Inscribed circle Area: " + inscrarea);
	System.out.println ("Circumscribed circle Area: " + circumarea);

	}
}