hi all programmer

Question

i have this question :
Suppose you have a deque D containing the numbers (1,2,3,4,5,6,7,8), in this order. Suppose
further that you have an initially empty queue Q. Give a code fragment that uses only D and Q (and no
other variables) and results in D storing the elements in the order (1,2,3,5,4,6,7,8).

and I try to use this code:

ArrayDeque<Integer> D = new ArrayDeque<>();
D.addAll(List.of(1, 2, 3, 4, 5, 6, 7, 8));
Queue<Integer> Q = new ArrayDeque<>();
while (!D.isEmpty()) {
Q.offer(D.poll());
if (!D.isEmpty()) {
D.offer(D.poll());
}
}
System.out.println("D: " + D);
System.out.println("Q: " + Q);

I want swapped just between 4 and 5

but I get wrong output why?
please who can help me?

Answer 1

deary
I think D.offer(D.poll()); does nothing

Answer 2

Rain

yes it's right

Answer 3

deary ,

Did you word the problem right? It looks like you said D has to end up in the same state it started in.

Answer 4

deary ,

Oh, I see. 4 and 5 are swapped.

Would you remove all the extra language tags, and just leave the language tag that your code is in please?

Answer 5

Is it a challenge.

If so, please post at "Post your Coding Challenge Here".

Please read the first post before posting anything.

https://www.sololearn.com/discuss/1270852/?ref=app

Answer 6

Wong Hei Ming

this is not Challenge this is problem in this question and i put code in my post
and your link are posted in answer is not working

Thank you

Answer 7

Rain

ok
did you know about this question

Answer 8

deary ,

To address a comment to someone, type @ and choose them from the list of names that appears.

Now that there's only one tag, I know it's a Java program.

I took Introduction to Java here, but then I became a Python fan and switched, so I don't know ArrayDeque or Queue, but I'm looking on oracle.com about it.

Your code is incomplete for Java. There's no main, etc. If you could post a link with the whole code intact, it would be easier to run and analyze.

Meanwhile, maybe a Java fan will respond.

Answer 9

deary ,

Do you know how to post a link to your code?