剑指Offer24-链表中倒数第k个结点

在数据结构与算法-链表必写题汇总(快慢指针、哨兵等)中，有类似的题目，使用快慢指针即可解决，但剑指的这题直接返回即可，之前写的文章中的那题，还需要对倒数第k个结点执行删除操作，其实也很简单，注意每次到目标节点的前驱节点为止，才能删除该目标结点。

# -*- coding:utf-8 -*-
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution:
    def FindKthToTail(self, head, k):
        # write code here
        if head is None:
            return None
        slow = head
        fast = head
        between = 0
        
        while between != k - 1:
            fast = fast.next
            if fast is None:
                return None
            between += 1
        while fast.next is not None:
            slow = slow.next
            fast = fast.next
            
        return slow