class DrinksMachineFuncs
{

  public static boolean cheaper(DrinksMachine a,DrinksMachine b)
  // A method which says whether drinks machine a is cheaper than
  // drinks machine b.
  {
   return a.showPrice()<b.showPrice();
  }

  public static DrinksMachine cheapestMachine(DrinksMachine a,DrinksMachine b)
  // A method which returns the cheaper of two drinks machines
  {
   if(a.showPrice()<b.showPrice())
      return a;
   else
      return b;
  }

  public static DrinksMachine cheapestMachine 
  (DrinksMachine a,DrinksMachine b,DrinksMachine c)
  // A method which returns the cheapest of three drinks machines
  {
   if(a.showPrice()<b.showPrice())
      if(c.showPrice()<a.showPrice())
         return c;
      else  
         return a;
   else if(b.showPrice()<c.showPrice())
      return b;
   else
      return c;
  }

}