题解 | #链表中倒数最后k个结点#

双指针

# 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 pHead ListNode类 
# @param k int整型 
# @return ListNode类
#
class Solution:
    def FindKthToTail(self , pHead , k ):
        # write code here
        left,right=pHead,pHead
        for _ in range(k):
            if not right:
                return None
            right=right.next
        while right:
            right=right.next
            left=left.next
        return left