贴一下自己的暴力解法和双指针比较妙的解法：
class Solution:
def getKthFromEnd(self, head: ListNode, k: int) -> ListNode:
### 双指针
left,right = head, head
for _ in range(k):
right=right.next
while(right!=None):
left=left.next
right = right.next
return left
## 暴力解法
# length = 1
# tmp = head
# while(tmp.next!=None):
# length+=1
# tmp = tmp.next
# n = length-k
# for _ in range(n):
# head = head.next
# return head
