aloalgoReverse Linked List
Medium
You are given the head of a singly linked list.
Your task is to reverse this linked list.
Return the head of the newly reversed list.
Example 1
Input
1 → 2 → 3 → null
Output
3 → 2 → 1 → null
Explanation:
The list is reversed node by node.
Example 2
Input
1 → 2 → null
Output
2 → 1 → null
Explanation:
A two-node list is reversed.
Example 3
Input
None
Output
None
Explanation:
An empty list remains empty.
Input
1 → 2 → 3 → null
Output
3 → 2 → 1 → null