LeetCode 328 Odd Even Linked List in Java

In this post I will try three implementations of the function of interest for LeetCode 328 Odd Even Linked List problem using the Java programming language.

Given a singly linked list, 
group all odd nodes together followed by the even nodes.

Please note here we are talking about the node number and not the value in the nodes!!!

You should try to do it in place. 
The program should run in O(1) space complexity and O(nodes) time complexity.

Constraints:

o The relative order inside both the even and odd groups should remain as it was in the input.
o The first node is considered odd, the second node even and so on ...
o The length of the linked list is between [0, 10^4].

We are given a singly linked list. We need to group all `odd` nodes together followed by the `even` nodes. Please note the definition of what makes a node `odd` and `even`. It is not the value in the node but the position of the node in the linked list. Continue reading “LeetCode 328 Odd Even Linked List in Java”