You are given the head of a doubly linked list, which contains nodes that have a next pointer and a previous pointer.
Return an integer array which contains the elements of the linked list in order.
Example 1:
Input: head = [1,2,3,4,3,2,1]
Output: [1,2,3,4,3,2,1]
Example 2:
Input: head = [2,2,2,2,2]
Output: [2,2,2,2,2]
Example 3:
Input: head = [3,2,3,2,3,2]
Output: [3,2,3,2,3,2]
Constraints:
[1, 50].1 <= Node.val <= 50Loading editor...
[1,2,3,4,3,2,1]