Untitled

import java.io.*;
import java.util.*;

interface Drink {
    int getPrice();
    String getName();
    int getQuantityLeft();
    void serveDrink();
}

class ServeDrinkSummary {
    Drink servedDrink;
    int change;

    ServeDrinkSummary(Drink servedDrink, int change) {
        this.servedDrink = servedDrink;
        this.change = change;
    }
}

class OutOfStockException extends Exception {
    public OutOfStockException(String message) {
        super(message);
    }
}

class InsufficientMoneyException extends Exception {
    public InsufficientMoneyException() {
        super("Insufficient money");
    }
}

class VendingMachine {
    private final Drink[] drinks = new Drink[3];

    void registerDrink(int buttonIdx, Drink drink) {
        drinks[buttonIdx] = drink;
    }

    ServeDrinkSummary dispatch(int buttonPressed, int money)
            throws OutOfStockException, InsufficientMoneyException {
        Drink drink = drinks[buttonPressed];
        if (drink.getQuantityLeft() == 0) {
            throw new OutOfStockException(drink.getName() + " is out of stock");
        } else if (money < drink.getPrice()) {
            throw new InsufficientMoneyException();
        } else {
            drink.serveDrink();
            int change = money - drink.getPrice();
            return new ServeDrinkSummary(drink, change);
        }
    }
}

class Coke implements Drink {
    private int price;
    private String name;
    private int quantityLeft;

    public Coke(int price, String name, int quantityLeft) {
        this.price = price;
        this.name = name;
        this.quantityLeft = quantityLeft;
    }

    public int getPrice() {
        return this.price;
    }

    public String getName() {
        return this.name;
    }

    public int getQuantityLeft() {
        return this.quantityLeft;
    }

    public void serveDrink() {
        if (this.quantityLeft > 0)
            this.quantityLeft -= 1;
    }
}

class Fanta implements Drink {
    private int price;
    private String name;
    private int quantityLeft;

    public Fanta(int price, String name, int quantityLeft) {
        this.price = price;
        this.name = name;
        this.quantityLeft = quantityLeft;
    }

    public int getPrice() {
        return this.price;
    }

    public String getName() {
        return this.name;
    }

    public int getQuantityLeft() {
        return this.quantityLeft;
    }

    public void serveDrink() {
        if (this.quantityLeft > 0)
            this.quantityLeft -= 1;
    }
}

class Sprite implements Drink {
    private int price;
    private String name;
    private int quantityLeft;

    public Sprite(int price, String name, int quantityLeft) {
        this.price = price;
        this.name = name;
        this.quantityLeft = quantityLeft;
    }

    public int getPrice() {
        return this.price;
    }

    public String getName() {
        return this.name;
    }

    public int getQuantityLeft() {
        return this.quantityLeft;
    }

    public void serveDrink() {
        if (this.quantityLeft > 0)
            this.quantityLeft -= 1;
    }
}