package oop2a;

import java.util.Scanner;

class Kwadrat
{
    public Kwadrat()
    {
       bok = 0;
    }

    public Kwadrat( double bok )
    {
        ustawBok( bok );
    }

    public void ustawBok( double bok )
    {
      if( bok >= 0 )
          this.bok = bok;
    }
    public double podajBok()
    {
        return bok;
    }
    public double pole()
    {
        return bok * bok;
    }

    protected double bok;
}

class Szescian extends Kwadrat
{
    public Szescian()
    {
      super();
    }
    public Szescian( double bok )
    {
        super( bok );
    }
    @Override
    public double pole()
    {
        return 6 * super.pole();
    }
}

public class OOP2a
{
    public static void main(String[] args)
    {
        Scanner we = new Scanner( System.in );
        double bok;

        System.out.print( "Podaj długość boku: " );
        bok = we.nextDouble();

        Szescian k = new Szescian( bok );

        //k.ustawBok( bok );

        System.out.println( "Pole: " + k.pole() );

    }

}