题目

给你一个链表的头节点 head ，旋转链表，将链表每个节点向右移动 k 个位置。

示例 1：

输入：head = [1,2,3,4,5], k = 2
输出：[4,5,1,2,3]

解

class Solution {
    public ListNode rotateRight(ListNode head, int k) {
        if (head == null || head.next == null) {
            return head;
        }

        ListNode p1 = head;
        int count = 1;
        while (p1.next != null) {
            count++;
            p1 = p1.next;
        }
        p1.next = head;

        k = k% count;
        ListNode p2 = head;
        for (int i = 0; i < count - k - 1; i++) {
            p2 = p2.next;
        }

        ListNode result = p2.next;
        p2.next = null;
        return result;

    }
}