program to print linked list elementsbin reverse manner code example
Example 1: reverse linked list in java to get both head and tail
/*
public class ListNode {
public int val;
public ListNode next;
public ListNode(int x) { val = x; next = null; }
}
*/
public static ListNode[] reverse_linked_list(ListNode head) {
ListNode prev = null;
ListNode current = head;
ListNode next;
ListNode tail = head;
while (current != null) {
next = current.next;
current.next = prev;
prev = current;
current = next;
}
head = prev;
ListNode[] result = {head, tail};
return result;
}
Example 2: revese the linked list java
Easiest way
public static LinkedList reverse(LinkedList head) {
LinkedList prevAddress = null;
LinkedList currentAddress = head;
LinkedList nextAddress = head.next;
while(nextAddress!=null) {
currentAddress.next = prevAddress;
prevAddress = currentAddress;
currentAddress = nextAddress;
nextAddress= currentAddress.next;
currentAddress.next = prevAddress;
}
head = currentAddress;
return head;
}
Just try to visualize its all about pointers game. :-)
NO GFG ANSWER