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]

示例 2:

输入:head = [0,1,2], k = 4

输出:[2,0,1]

代码实现:

class Solution {
public ListNode rotateRight(ListNode head, int k) {
if (k == 0 || head == null || head.next == null) {
return head;
}
int n = 1;
ListNode iter = head;
while (iter.next != null) {
iter = iter.next;
n++;
}
int add = n - k % n;
if (add == n) {
return head;
}
iter.next = head;
while (add-- > 0) {
iter = iter.next;
}
ListNode ret = iter.next;
iter.next = null;
return ret;
}
}