import java.util.Scanner;
class Box {
float PI =(float) 3.14;
float r;
float height;
void setBox(float r2,float h){
r=r2;
height=h;
}
float volume(){
float V=(float)(r*r*height*PI);
return V;
}
public static void main(String[] args) {
Box b=new Box();
Scanner reader = new Scanner(System.in);
System.out.println("请输入底面半径和高：");
b.r=reader.nextInt();
b.height=reader.nextInt();
System.out.println(b.volume());
}
}