[nowcoder56]删除链表中重复的结点

题目描述

在一个排序的链表中，存在重复的结点，请删除该链表中重复的结点，重复的结点不保留，返回链表头指针。 例如，链表1->2->3->3->4->4->5 处理后为 1->2->5

题目链接： https://www.nowcoder.com/practice/fc533c45b73a41b0b44ccba763f866ef

分析

参考代码

-*- coding:utf-8 -*-
class ListNode:
def __init__(self, x):
    self.val = x
    self.next = None

class Solution:
def deleteDuplication(self, pHead):
    # write code here
    d=set()
    single=set()
    p=pHead
    while(p!=None):
        if(p.val not in d):
            d.add(p.val)
            single.add(p.val)
        else:
            if(p.val in single):
                single.remove(p.val)
        p=p.next
    p=pHead
    realHead=None
    real=None
    i=0
    while(p):
        i+=1
        if(p.val in single):
            if(realHead==None):
                realHead=p
                real=p
            else:
                real.next=p
                real=p
        p=p.next
    if(real!=None):
        real.next=None
    return realHead