Reverse a Custom Linked List | Dataford Interview Questions

Blurb's preview pipeline stores ordered page-preview records in a custom singly linked list. Implement reverse_linked_list(head) to reverse the list in place and return the new head.

Each node is provided by the interviewer and has two fields: value, containing any page-preview record, and next, containing another node or None. Do not create replacement nodes or use an auxiliary collection.

Formal Specification

Input: head, either a Node object representing the first node of a singly linked list or None.
Output: The Node object that was previously the tail, now serving as the new head. Return None for an empty list.
The function must preserve every node and reverse each next pointer.

Constraints

0 <= number of nodes <= 10^5
Each node has fields value and next
The list is singly linked and acyclic
value may be any Python object
Use O(1) auxiliary space

Function Signature

def reverse_linked_list(head):

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