题解 | #链表中环的入口结点#
链表中环的入口结点
https://www.nowcoder.com/practice/253d2c59ec3e4bc68da16833f79a38e4
# -*- coding:utf-8 -*- # class ListNode: # def __init__(self, x): # self.val = x # self.next = None class Solution: def EntryNodeOfLoop(self, pHead): # write code here # a+b+c+b=2*(a+b) # a+b+(b+c)n=2(a+b) slow = pHead fast = pHead while fast != None and fast.next != None: fast = fast.next.next slow = slow.next if fast == slow: while pHead != slow: pHead = pHead.next slow = slow.next return slow return None#23届找工作求助阵地#