g0101_0200.s0143_reorder_list.readme.md Maven / Gradle / Ivy
143\. Reorder List
Medium
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`    © 2015 - 2025 Weber Informatics LLC | Privacy Policy