Preparing this workspace.
Reorder List
Difficulty: Medium
Category: DSA
Topics: Linked List, Two Pointers, Stack, Recursion
Asked at: Facebook, Amazon, Splunk
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`
Opening the problem
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