Leetcode61旋转链表

代码：

/**
 * 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(k==0||head==null||head.next==null)return head;
        ListNode newHead = head;
        ListNode cur = head;
        ListNode end = head;
        ListNode newEnd = head;
        int n=1;
        while(cur.next!=null){
            n++;
            cur = cur.next;
            end = cur;
        }
        cur = head;
        k%=n;
        if(k==0)return head;
        int i=0;       
        for(;i