题解 | #链表中环的入口结点#

# -*- coding:utf-8 -*-
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
# 这里可以观察到每个节点的值是有顺序的，因此可以设置一个计数器，通过判断节点值的方法来判断是否有环
class Solution:
    def EntryNodeOfLoop(self, pHead):
        count = 1
        while pHead != None:
            
            if pHead.val < count:
                return pHead
            pHead = pHead.next
            count += 1

        return None