旋转链表

# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param head ListNode类 
# @param k int整型 
# @return ListNode类
#
class Solution:
    def rotateLinkedList(self , head: ListNode, k: int) -> ListNode:
        # write code here
        l_len = 0
        point = head
        while point is not None:
            l_len += 1
            point = point.next
        if l_len == 0:
            return head

        k = k%l_len
        if k == 0:
            return head

        point = head
        next_point = point
        for i in range(k):
            next_point = next_point.next

        while next_point.next is not None:
            next_point = next_point.next
            point = point.next

        new_head = point.next
        point.next = None
        next_point.next = head
        return new_head