Question

Re-do Problem 1, but now implement the following method:

i must use this code :-

public static BagInterface intersection (BagInterface bagA, BagInterface bagB)

and here how my java program must work

This method must return a new bag which is the intersection of the two bags: bagA and bagB. An element appears in the intersection of two bags the minimum of the number of times it appears in either. For example, {1,1,2} ∩{1,1,2,2,3}= {1,1,2}. Do not forget to state the big O of your method implementation.

useing netbeans java

Answer 1

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Data Structures - Creating a Bag in Java

java data-structures blackjack bag

I am working on creating a bag of cards for a blackjack game in my CS course. This particular project requires that I create a bag to hold my 52 cards. Keep in mind that I am trying to assure that there are 4 types of each card, Queens, Kings, Jacks, and Aces all included. I keep getting an error in my main: Exception in thread "main" java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Ljava.lang.Integer; at Main.main(Main.java:14)

If anyone can please help me to get this bag running properly, it would be greatly appreciated.

Here is my code:

public class Bag<T> 
{
    T[] cards;
    private final int DEFAULT_CAPACITY = 52;
    private int numberOfEntries;

    public Bag()
    {
        this.cards = (T[]) new Object[DEFAULT_CAPACITY];
        numberOfEntries = DEFAULT_CAPACITY;
    }

    public int getCurrentSize()
    {
        return numberOfEntries;
    }

    public boolean isFull()
    {
        return numberOfEntries == DEFAULT_CAPACITY;
    }

    public boolean isEmpty()
    {
        return numberOfEntries == 0;
    }

    public boolean add(T newItem)
    {
        boolean result = true;
        if(isFull())
        {
            result = false;
        }

        else
        {
            cards[numberOfEntries] = newItem;
            numberOfEntries++;
        }

        return result;
    }

    public boolean remove()
    {
        boolean result = true;
        if(numberOfEntries > 0)
        {
            numberOfEntries--;
        }
        else
            result = false;

        return result;
    }

    public void clear()
    {
        numberOfEntries = 0;
    }

    public int getNumOf(T anItem)
    {
        int count = 0;

        for(int i = 0; i < cards.length; i++)
        {
            if(anItem.equals(cards[i]))
            {
                count++;
            }
        }

        return count;
    }

    public boolean contains(T anItem)
    {
        boolean found = false;

        for (int i = 0; !found && (i < numberOfEntries); i++)
        {
            if(anItem.equals(cards[i]))
            {
                found = true;
            }
        }

        return found;
    }

    public T Grab()
    {
        int random = (int)(Math.random() * DEFAULT_CAPACITY);
        if(!isEmpty())
        {
            cards[random] = null;
            numberOfEntries--;
            return cards[random];
        }

        else
            return null;
    }

    public int getFrequencyOf(T anItem)
    {
        int counter = 0;

        for(int i = 0; i < numberOfEntries; i++)
        {
            if(anItem.equals(cards[i]))
            {
                counter++;
            }
        }

        return counter;
    }

}

public class Main {

    public static void main(String[] args)
    {
        //Accesses the Bag class
        Bag<Integer> bag = new Bag<Integer>();

        //Sets up 52 cards (13*4). 4 of each type
        for (int i = 1; i <= 13; i++) 
        {

            for (int j = 1; j <= 4; j++) {
                bag.cards[i*j] = i;
                //if the card is an ace and not equal to 1
                if(i == 1)
                    bag.cards[i*j] = 11;
                //handles the king, queen, and jack cards
                else if (i==11||i==12||i==13)
                    bag.cards[i*j] = 10;    
            }

            bag.add(1);
        }
    }
}