/******************************************************************************
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import java.util.*;
import java.text.DecimalFormat;
public class Main
{
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
int a = scan.nextInt();
if(a>=20 && a<=30){
float area = (float)Math.PI*a*a;
String s1 =String.format("%.2f",area);
System.out.println(s1);
//round off
DecimalFormat dc = new DecimalFormat("#.##");
System.out.println(dc.format(area));
System.out.printf("%.2f",area);
}
}
}
