Odd Even Linked List
CodingOnsiteSoftware EngineerReported Jan, 2026
Examples
Example 1:
Input: head = [1,2,3,4,5]
Output: [1,3,5,2,4]
Example 2:
Input: head = [2,1,3,5,6,4,7]
Output: [2,3,6,7,1,5,4]
Example 1:
Input: head = [1,2,3,4,5]
Output: [1,3,5,2,4]
Example 2:
Input: head = [2,1,3,5,6,4,7]
Output: [2,3,6,7,1,5,4]
Given the head of a singly linked list, group all nodes at odd indices together followed by the nodes at even indices, and return the reordered list.
The first node is considered odd, the second node is even, and so on. Preserve the relative order within both groups.
0 <= number of nodes <= 10^4-10^6 <= Node.val <= 10^6