comparing top of queue to an array list element

Question

I have written a method in Java which takes in an array list which contains another array of size 3 as each element. e.g. {{0,0,0},{1,0,0},{1,1,0}...}.

The method works out if the head of the queue is inside this array list.

The queue has the same structure as the array list.

public static Queue<Integer[]> q = new LinkedList<Integer[]>();
List<Integer[]> outcomes = new ArrayList<Integer[]>();

Public static boolean outcomeSearch(List<Integer[]> outcomes){
 boolean check = false;
 for (int i=0; i<outcomes.size(); i++){
     if (q.peek() == outcomes.get(i)){
         check = true;
     }
 }
 return check;
}

For some reason, I can't get the if statement to work. In practice, the head of the queue is {0,0,0} and outcomes is {{0,0,0},{8,0,0},{0,5,0}...}. So the for loop should turn the check boolean true in the first iteration. But it doesn't.

This problem is comparing elements inside the array, not the whole array itself.

score 0 · Answer 1 · answered Nov 30 '17 at 18:00

0

Looks like the problem is probably the way the queue was declared, and therefore the way it is implemented in the method. Check if you are declaring the queue as static or instance variable of the class.

answered Nov 30 '17 at 18:00

ferpujol

11
3

We can't know since OP hasn't shown us the definition of q, but it also could be the way they are compared. – max Nov 30 '17 at 18:07
The queue is declared like this: public static Queue q = new LinkedList(); – Bob Mamfis Nov 30 '17 at 18:23
Try printing your q LinkedList to check if it is not empty. I don't see anything wrong in your code. – ferpujol Dec 01 '17 at 22:57

comparing top of queue to an array list element

1 Answers1