How to remove and return array list index

Question

I'm trying to remove and return the object at the first index of my array list called deck. My code returns the object at index 0 post remove() being called, so it's always returning the second index of the original deck array list. I'm not sure how to return the index at 0, THEN remove it.

public Card dealCard()
{
    int i = 0;                
    Card topCard = null;
    if(deck.size() > 0)
    {
        topCard = deck.get(i);
        deck.remove(topCard);        
    }           
    else
    {
        System.out.println("Fatal Error. Program now exiting.");
        System.exit(0);
    }
    return topCard;
}

Does it return the 0th obj when you comment "deck.remove(topCard); " ? — Dula wnRp
– Dula wnRp, Commented Apr 14, 2018 at 10:39
It's wrong because it is returning the element at index 0 AFTER remove() is called, instead of returning the index at 0 of the original array list, THEN removing it. — CSmizzle
– CSmizzle, Commented Apr 14, 2018 at 10:46
No. topCard = deck.get(i) sets topCard to the card that was the i'th prior to being removed, then deck.remove(topCard) removes that card from deck but doesn't change topCard. — Kevin Anderson
– Kevin Anderson, Commented Apr 14, 2018 at 11:22

baao · Accepted Answer · 2018-04-14 10:42:38Z

1

remove(int index) returns the element at index when you pass an index to it. So all you have to do is

if(deck.size() > 0)
{
    topCard = deck.remove(i);
}

This will set topCard to whatever is at index i and remove the element from the list

answered Apr 14, 2018 at 10:42

baao

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1 Comment

CSmizzle Over a year ago

This still returns the first index after remove() is called, so it's missing the index 0 of the original deck array list.

Muhammad Usman · Accepted Answer · 2018-04-14 10:40:15Z

0

Try this:

public Card dealCard()
{
    int i = 0;                
    Card topCard = null;
    //topCard.equals(deck.get(i));
    //deck.remove(topCard);
    if(deck.size() > 0)
    {
        topCard = deck.get(i);
        deck.remove(i);
        //temp = deck.remove(topCard);
        //temp.equals(deck.remove(topCard));           
    }           
    else
    {
        System.out.println("Fatal Error. Program now exiting.");
        System.exit(0);
    }
    return topCard;
}

answered Apr 14, 2018 at 10:40

Muhammad Usman

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2 Comments

CSmizzle Over a year ago

Still causing same issue unfortunately.

CSmizzle Over a year ago

I'm not sure how to do that. Sorry, new here.

Ninja · Accepted Answer · 2018-04-14 10:42:31Z

0

Don't remove what you store in the variable top card, instead remove the item by its index.

public Card dealCard() {
int i = 0;                
Card topCard = null;
if(deck.size() > 0)
{
    topCard = deck.get(i);
    deck.remove(i);        
}           
else
{
    System.out.println("Fatal Error. Program now exiting.");
    System.exit(0);
}
return topCard;

answered Apr 14, 2018 at 10:42

Ninja

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1 Comment

CSmizzle Over a year ago

Still causes same issue.

Aashutosh Kumar · Accepted Answer · 2018-04-14 10:45:44Z

0

Remove Item from list using index

deck.remove(i);

answered Apr 14, 2018 at 10:45

Aashutosh Kumar

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