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Linked List Reversal
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Linked List Reversal

EasyPython

Problem

Given the head of a singly linked list, reverse the list and return the new head.

Implement a function that takes the head node of the list and returns the head node after reversal. The list nodes are defined as:

  • val: integer value stored in the node
  • next: reference to the next node, or None

Constraints

  • 0 <= number of nodes <= 10^5
  • -10^9 <= Node.val <= 10^9
  • The list may be empty
  • Reverse the list in-place using O(1) extra space

Function Signature

def reverse_linked_list(head):
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