import java.util.Random;

class PPJ
{
    public static void main (String[] Args)
    {
        Kwadrat kwadrat = new Kwadrat(3);
        kwadrat.show();

        Walec walec = new Walec(2.0, 3.0);
        walec.show();

        Osiol osiol = new Osiol(0.5);

        while(!osiol.czyLata())
        {
            Balon balon = new Balon();
            System.out.println("Balon " + balon.podajUdzwig());
            osiol.dodajBalon(balon);
        }
        System.out.println("Ja latam!!!");

        Wyraz wyraz = new Wyraz();
        wyraz.dodajZnak('a');
        for(int i=0;i<1000;i++)
        {
            wyraz.dodajZnak('c');
        }

        System.out.println(wyraz.length());
        wyraz.wyswietl();
    }
}

class Kwadrat
{
    private int bok;

    public Kwadrat(int bok)
    {
        this.bok = bok;
    }

    public void show()
    {
        System.out.println("Pole: " + bok*bok + "  Objetosc: " + bok*bok*bok);
    }
}

class Walec
{
    private double promien;
    private double wysokosc;

    public Walec(double promien, double wysokosc)
    {
        this.promien = promien;
        this.wysokosc = wysokosc;
    }

    public void show()
    {
        double ppp = promien*promien*Math.PI;
        System.out.println("PPP: " + ppp + "  Objetosc: " + ppp*wysokosc);
    }
}

class Balon
{
    private double hel;
    private final double m3naKg = 6.0/ 1000 / 0.007;

    public Balon()
    {
        Random random = new Random();
        hel = 0.005 + (0.009 - 0.005) * random.nextDouble();
    }

    public double podajUdzwig()
    {
        return m3naKg * hel;
    }
}

class Osiol
{
    private double masa;
    private Balon[] balony;
    private int iloscBalonow;
    private double udzwig;

    public Osiol(double masa)
    {
        this.masa = masa;
        balony = new Balon[(int)Math.ceil(masa/0.005)];
        iloscBalonow = 0;
    }

    public void dodajBalon(Balon balon)
    {
        balony[++iloscBalonow] = balon;
        udzwig += balon.podajUdzwig();
    }

    public boolean czyLata()
    {
        return udzwig > masa;
    }
}

class Wyraz
{
    private char[] chars;
    private int length;

    public Wyraz()
    {
        chars = new char[100];
        length = 0;
    }

    public void dodajZnak(char znak)
    {
        if(length >= chars.length)
        {
            char[] copy = new char[length+101];
            System.arraycopy(chars, 0, copy, 0, chars.length);
            chars = copy;
        }
        chars[length++] = znak;
    }

    public void wyswietl()
    {
        for(int i=0;i<length;i++)
        {
            System.out.print(chars[i]);
        }
    }

    public int length()
    {
        return length;
    }
}