#!/user/bin/env python

# coding=utf-8

"""

@project : algorithmPython

@ide : PyCharm

@file : deleteDuplicates

@author : illusion

@desc : 82. 删除排序链表中的重复元素 II https://leetcode-cn.com/problems/remove-duplicates-from-sorted-list-ii/

@create : 2020-08-30 16:11:21

"""

# Definition for singly-linked list.

class ListNode:

def __init__(self, x):

self.val = x

self.next = None

class Solution:

def deleteDuplicates(self, head: ListNode) -> ListNode:

if not head:

return None

new_head = ListNode(-1)

new_head.next = head

now = new_head

while now.next and now.next.next:

if now.next.val == now.next.next.val:

repeat_val = now.next.val

while now.next and now.next.val == repeat_val:

now.next = now.next.next

else:

now = now.next

return new_head.next