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Practice Odd Even Linked List

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Medium#328
LeetCode Problem

Odd Even Linked List

Linked List

Problem Statement

Given the head of a singly linked list, group all the nodes with odd indices together followed by the nodes with even indices, and return the reordered list. The first node is considered odd, and the second node is even, and so on. Note that the relative order inside both the even and odd groups should remain as it was in the input. You must solve the problem in O(1) extra space complexity and O(n) time complexity.

Source: Odd Even Linked List on LeetCode. Use the original task for its coding environment and submissions.

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]

Constraints

The number of nodes in the linked list is in the range [0, 10^4].
-10^6 <= Node.val <= 10^6

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2 Add Two Numbers Medium19 Remove Nth Node From End of List Medium21 Merge Two Sorted Lists Easy23 Merge k Sorted Lists Hard24 Swap Nodes in Pairs Medium
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