package work03;
import java.util.Scanner;
public class Helloworld {
public static void main(String[] args) {
System.out.println("请输入半径：");
Scanner sc = new Scanner(System.in);
int r = sc.nextInt();
double area = 0;
area = rr3.14;//面积
System.out.println("该圆的面积为："+area);
}
}
