Find the area of a circle with a specified radius

package cn.tedu.basic;
import java.util.Scanner;
/ **

• Requirements: find the area of ​​the specified radius circle

• Formula: The area of ​​a circle: Π r r
  */
  public class Test3_CircleArea {

  public static void main(String[] args) { //2. Prompt the user to enter the radius value to be calculated: System.out.println("Please enter the radius value you want to calculate:"); //3. Use to define variables To save the radius value //4. Receive the radius value entered by the user //Scanner needs to be imported when using the package double r = new Scanner(System.in).nextDouble();
  
  
  
  
  
  

   //5.根据用户在键盘上输入的半径值计算圆的面积
   double circlearea = 3.14*r*r;
   System.out.println("圆的面积为:"+circlearea);
  

  }

}