import java.applet.*;
import java.awt.*;
import java.awt.event.*;

public class Bank extends Applet {

    private TextArea display1 = new TextArea(4, 25);
    private TextArea display2 = new TextArea(4, 25);

    private Regular account1 = new Regular();
    private Gold account2 = new Gold();

    public void init(){
        add(display1);
        add(display2);

        account1.open(-200, "Poor Person");
        account2.open(10000, "Bill Gates");

        displayAccount(account1, display1);
        displayAccount(account2, display2);
    }

    public void displayAccount(Account account, TextArea display) {
       display.setText(account.getPerson() + "\n"); // polymorphism
       display.append(account.checkOverdrawn()+ "\n"); // polymorphism
       display.append("interest is " + account.calculateInterest()); // polymorphism
    }
}

class Account {

    int amount;
    private String person;

    public void open(int initialAmount, String person) {
        amount = initialAmount;
        this.person = person;
    }

    public String getPerson() {
        return person;
    }

    public int getAmount() {
        return amount;
    }

    public String checkOverdrawn() {
        return "no check";
    }

    public int calculateInterest() {
        return 0;
    }

}

class Regular extends Account {

    public String checkOverdrawn() {
        if (amount < 0)
            return "account is overdrawn";
        else
            return "overdraft is OK";
    }

    public int calculateInterest() {
        return (amount * 5 / 100);
    }
}

class Gold extends Account {       

    public String checkOverdrawn() {
        return "account is never overdrawn";
    }

    public int calculateInterest() {
        return (amount * 6 / 100) - 100;
    }
}