You are given the head of a singly linked-list.

The positions of a linked list of length = 7 for example, can intially be represented as:

[0, 1, 2, 3, 4, 5, 6]

Reorder the nodes of the linked list to be in the following order:

[0, 6, 1, 5, 2, 4, 3]

In the general case, label the nodes by their original zero-based positions from 0 to n - 1. After reordering, those original positions appear in this order:

[0, n-1, 1, n-2, 2, n-3, ...]

These numbers represent node positions, not the values stored in the nodes.

You may not modify the values in the list's nodes, but instead you must reorder the nodes themselves.

Example 1:

Input: head = [2,4,6,8]

Output: [2,8,4,6]

Example 2:

Input: head = [2,4,6,8,10]

Output: [2,10,4,8,6]

Constraints:

• 1 <= Length of the list <= 1000.
• 1 <= Node.val <= 1000