定义前置指针,记录上一个值,遍历链表,获取要删除的节点
# 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 val int整型
# @return ListNode类
#
class Solution:
def deleteNode(self , head: ListNode, val: int) -> ListNode:
# write code here
if head.val == val: return head.next
head_new = head
pre_node = ListNode(-1)
pre_node.next = head_new
while head_new and head_new.val != val:
pre_node = pre_node.next
head_new = head_new.next
pre_node.next = head_new.next
return head