Remove duplicates from Sorted List II

https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/

Remove duplicates from Sorted List II

Given a sorted linked list, delete all nodes that has duplicate numbers, leaving only distinct numbers from the Original list.

For example,
Given 1->2->3->3->4->4->5 , return 1->2->5 .
Given 1->1->1->2->3 , return 2->3 .

Title: Deleting all duplicate nodes of an ordered list

1 #Definition for singly-linked list.2 #class ListNode:3 #def __init__ (self, x):4 #self.val = x5 #Self.next = None6 7 classSolution:8     #@param {ListNode} head9     #@return {ListNode}Ten     defdeleteduplicates (Self, head): One         ifHead==noneorhead.next==None: A             returnHead -dummy=listnode (0) -dummy.next=Head thep=Dummy -tmp=Dummy.next -          whileP.next: -              whileTmp.next andP.next.val==tmp.next.val:#when the junction value of number 1th is equal to the value of number 2nd nodes. +Tmp=tmp.next#the pointer behind the number 2nd node continues to determine the number 3rd node, and then backwards and forwards until the while is not satisfied values are not equal . -                                                           #A duplicate node segment is marked before and after the pointer p and the TMP +             ifTmp==p.next:#Scenario 1: If no duplicates are judged by the above, the TMP pointer is not moved and is still in the initial p.next position AP=p.next#move p back one atTmp=p.next#The corresponding TMP is still in the P.next position after p, restarting the while P.next and the following loop judgment -             Else:#The situation 2:tmp moved, marked the repeating node segment, sandwiched between P and TMP 2 or more repeating nodes . -P.next=tmp.next#at this point, tmp.next that is the repeating segment after the linked list part directly connected to P, to achieve the deletion of the repeating segment -         returnDummy.next

Remove duplicates from Sorted List II