import java.util.Scanner;

public class Yuanzhu

{    private static double tij;

      public static void Tij()

    {    System.out.println("input r");

         Scanner a = new Scanner(System.in);

         double r=a.nextDouble();

         System.out.println("input l");

         Scanner ga = new Scanner(System.in);

         double gao=ga.nextDouble();

          tij=3.14*r*r*gao;

          System.out.println("print s:"+tij);

    }

public static void main(String[] args)

{ Tij(); }

}

这里是一个求圆柱体积的代码。