In a TATA Elxsi embedded software module, a singly linked list of event nodes must be reversed before downstream processing. Given the head of a singly linked list, reverse the list and return the new head.
Implement a function that takes head, the first node of a singly linked list, or null if the list is empty.
head where each node has fields val and nextYou must reverse the list by changing node pointers, not by copying values into another structure.
Example 1
Input: head = [1, 2, 3, 4, 5]
Output: [5, 4, 3, 2, 1]
Explanation: Each node's next pointer is reversed, so the tail becomes the new head.
Example 2
Input: head = [7, 9]
Output: [9, 7]
Explanation: The second node points to the first, and the first becomes the tail.
[0, 5000]-5000 <= Node.val <= 5000O(n) time and O(1) extra spacehead = [1, 2, 3, 4, 5]Output[5, 4, 3, 2, 1]WhyThe links are reversed in-place, so the original tail becomes the new head.head = [7, 9]Output[9, 7]WhyAfter reversal, node `9` points to `7`, and `7` becomes the tail.The number of nodes is in the range [0, 5000]-5000 <= Node.val <= 5000Each node contains fields val and nextThe list is singly linkeddef reverse_linked_list(head):
