학교에서 자바공부하고있는데

Examine class VendingMachine without modifying it. In the code pad, try creating a vending machine, and experiment with the different methods on the vending machine. Then implement procedure buyChips in class Lab6 to do the following:

1.Create a new vending machine.
2.Repeatedly insert coins into the machine until the chips are released.
3.Take the chips from the machine.
4.Print "I got the chips: XYZ" where XYZ is the chips object that the machine gave you.

이게 문제입니당
 
/**
 * Example usage:
 *
 * VendingMachine machine = new VendingMachine();
 *
 * machine.insertCoin();
 * machine.insertCoin();
 * ...
 * ...
 * if (machine.chipsReleased())
 * {
 *     Chips chips = machine.getChips();
 *     System.out.println("I got the chips: " + chips);
 * }
 */
public class VendingMachine
{
    // This is private, so the user does not know the price of chips.
    private final int PRICE_OF_CHIPS = 6;</LI><LI>    private int coins;</LI><LI>    public VendingMachine()
    {
        coins = 0;
    }

  public void insertCoin()
    {
        while (coins < PRICE_OF_CHIPS)
        {
            System.out.println("Coin inserted...");
            coins++;
        }
       
    }

  public boolean chipsReleased()
    {
        return coins == PRICE_OF_CHIPS;
    }

  public Chips getChips()
    {
        // Reset the machine
        reset();
        // Magically create new chips on demand
        return new Chips();
    }

  private void reset()
    {
        coins = 0;
    }
}


이거랑

public class Chips
{
    public String toString()
    {
        return "Salt & Vinegar";
   
    }
}
이걸 줬어요


내가 만들어야할부분이
  public static void buyChips()
    {
        VendingMachine vm = new VendingMachine();
               
        while(coins < PRICE_OF_CHIPS)       
        {
            vm.insertCoin();
            
        }
               
        vm.chipsReleased();
        if(vm.chipsReleased())
        {
            Chips chips = vm.getChips();
            System.out.println("I got the chips: " + chips);
        }
        vm.getChips();
     }


이건데 도저히 모르겠음 ㅠㅠ
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