/*

Problem No: 61 Rotate List

URI: https://leetcode.com/problems/rotate-list/

Logic: Calculate the length of the linked linst and store each node in a seperate arraylist in the first pass and if the value

of k is less than length then rotation point will be length-k else multiple rotations happends this can be done by the following logic

till length - k > 0 the value of k is updated as k-length. Swap the next pointers for the rotation point and last node of the listarray

to length-k node and start respectively

*/

/**

* Definition for singly-linked list.

* public class ListNode {

* int val;

* ListNode next;

* ListNode() {}

* ListNode(int val) { this.val = val; }

* ListNode(int val, ListNode next) { this.val = val; this.next = next; }

* }

*/

class Solution {

public ListNode rotateRight(ListNode head, int k) {

if(head==null | k==0){

return head;

}

int length = 0;

int pivotPoint;

List<ListNode> store = new ArrayList<>();

while(true){

length++;

store.add(head);

head=head.next;

if(head==null){

break;

}

}

ListNode newHead = head;

while(k>length){

k-=length;

}

if(length==k){

return store.get(0);

}

newHead = store.get(length-k);

ListNode curr = newHead;

while(curr.next!=null){

curr=curr.next;

}

curr.next = store.get(0);

if(length-k!=0)

store.get(length-k-1).next=null;

else

store.get(store.size()-1).next=null;

return newHead;

}

}