public class Main
{
public static void main(String[] args)
{
Cerchio c1 = new Cerchio () ;
Cerchio c2 = new Cerchio ( 0.0 , 0.0 , 2.0 ) ;
System.out.println ( "\n \t\t\tCIRCONF.\t AREA" ) ;
System.out.println ( " \t\t\t (mt) \t (mq)" ) ;
System.out.format ( "\n 1° cerchio:\t%+15.4f\t%+15.4f\n" , c1.getCirconferenza() , c1.getArea() ) ;
System.out.format ( "\n 2° cerchio:\t%+15.4f\t%+15.4f\n" , c2.getCirconferenza() , c2.getArea() ) ;
System.out.format ( "\n 3° cerchio:\t%+15.4f\t%+15.4f\n" , Cerchio.circonferenza(3.0) , Cerchio.area(3.0) ) ;
}
}
class Cerchio
{
public double Cx , Cy , r ;
Cerchio () { Cx = 0.0 ; Cy = 0.0 ; r = 1.0 ; } //semplice costruttore
Cerchio ( double x , double y , double l ) { Cx = x ; Cy = y ; r = l ; } //costruttore parametrico
static double circonferenza ( double l ) { return 2 * Math.PI * l ; }
static double area ( double l ) { return Math.PI * l * l ; }
double getCirconferenza () { return circonferenza ( r ) ; }
double getArea () { return area ( r ) ; }
}
