Can we reverse a linked list in less than O(n)?

It is not possible to reverse a simple singly linked list in less than O(n). A simple singly linked list can only be reversed in O(n) time using recursive and iterative methods. 

A doubly linked list with head and tail pointers while only requiring swapping the head and tail pointers which require lesser operations than a singly linked list can also not be done in less than O(n) since we need to traverse till the end of the list anyway to find the tail node.

This article is contributed by Abhishek and moharibishal