Reverse a linked list

Input list :

1->2->3->4->||

Output list :

4->3->2->1->||


 Code:

 Node reverse(Node head) {
        Node prev = null;
        Node current = head;
        while (current != null) {
            Node temp = current.next;
            current.next = prev;
            prev = current;
            current = temp;
        }
        head = prev;
        return head;
    }

Calling function:
head = list.reverse(head);

Illustration: 
(note : images in order left column first followed by right column)

i) Initialization and execution of first while loop

ii) Execution of second while loop



iii) Execution of final while loop and termination














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