Reverse a Singly Linked List

Given the head pointer of a singly linked list, implement a method to reverse the list and return the new head.

Example:
1->2->3 ==> 3->2->1

Need a hand? Try out these hints, one at a time.

The key here is to reverse the next link to the previous node at each step of the traversal till you reach the end of the list.

1. Create a temporary previous ListNode and initialize it to null.

2. Traverse through the list of nodes till the head node becomes null.

3. While traversing at each step, save the head.next i.e node next to the head node in a temporary front node i.e. ListNode front = head.next;

4. Track a node just behind the head node in a temporary node previous

5. Make the head's next link point to previous node i.e. head.next = previous

6. Move the temporary node previous one step ahead in the list by assigning the head node to the previous node i.e. previous = head

7. Move the head node one step ahead in the list by assigning the front node to the head node i.e. head = front

8. Return the previous node i.e. the new head at the end of the loop.

public ListNode reverseList(ListNode head) {
    



}

Java

Python