class DrinksMachineB implements DrinksMachine
{ // A drinks machine with a Change button

 private int balance,price;

 public DrinksMachineB(int p)
 {
  price=p;
 }

 public void addMoney(int pence)
 {
  balance+=pence;
 }

 public int showMoney()
 {
  return balance;
 }

 public int showPrice()
 {
  return price;
 }

 public String pressCoke()
 {
  if(balance<price)
     return "Nothing";
  else
     {
      balance-=price;
      return "Coke";
     }
 }

 public String pressFanta()
 {
  if(balance<price)
     return "Nothing";
  else
     {
      balance-=price;
      return "Fanta";
     }
 }

 public String pressChange()
 {
  int change=balance;
  balance=0;
  return change+"p";
 }

 public void changePrice(int newprice)
 {
  price=newprice;
 }
}