题解 | #删除链表的倒数第n个节点#

# 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 n int整型 
# @return ListNode类
#
class Solution:
    def removeNthFromEnd(self , head: ListNode, n: int) -> ListNode:
        i=1
        Test_node = ListNode(0)
        Test_node.next = head
        
        l1 = Test_node.next
        while l1.next:
            l1=l1.next
            i=i+1
        l1 = Test_node
        while l1:
            if i-n==0:
                l2 = l1.next
                l1.next = l2.next
                l2.next = None
                return Test_node.next
            l1 = l1.next
            i=i-1
        
        
        # write code here