You are given the head of a singly linked-list. The list can be represented as:

L₀ → L₁ → … → Ln - 1 → Ln

Reorder the list to be on the following form:

L₀ → Ln → L₁ → Ln - 1 → L₂ → Ln - 2 → …

You may not modify the values in the list's nodes. Only nodes themselves may be changed.

  Example 1:

Input: head = [1,2,3,4] Output: [1,4,2,3]

Example 2:

Input: head = [1,2,3,4,5] Output: [1,5,2,4,3]

  Constraints:

The number of nodes in the list is in the range [1, 5 * 10⁴].
1 <= Node.val <= 1000