如何在Java中打印以int为参数并返回double值的静态方法

Question

I'm having difficulty trying to print the result of the static method calcArea, which takes the int radius as parameter to calculate the area of a circle and returns the area.

Here's the code below 👇 Any help would be appreciated.

public class CircleArea {

    public int radius;

     public static void main(String[] args) {

          Scanner input = new Scanner (System.in);
          System.out.print("Enter the radius of the circle: ");

         int radius = input.nextInt();

          System.out.print("The area of the circle is:" + calcArea()); <-- ERROR HERE
     }

      public static double calcArea(int radius){          

          double  area = Math.PI * Math.pow(radius, 2);
          return area;          

      }
}

Answer 1

您对calcArea调用需要传入一个参数。可能是calcArea(radius) 。

Answer 2

The function calcArea() takes the value of radius and then returns area. To do this, you need to pass an argument to calcArea(). So, your code should be like this:

    System.out.print("The area of the circle is:" + calcArea(radius));

The error you're getting clearly points out that you're missing an argument.

Answer 3

call method calcArea, you need give a parameter,Here are the correct example"

public static void main(String[] args) {
      Scanner input = new Scanner (System.in);
      System.out.print("Enter the radius of the circle: ");
      int radius = input.nextInt();
      System.out.print("The area of the circle is:" + calcArea(radius));
 }