python 链表操作
Python3实现的判断环形链表算法示例本文实例讲述了Python3实现的判断环形链表算法。分享给大家供大家参考,具体如下:
给定一个链表,判断链表中是否有环。
方案一:快慢指针遍历,若出现相等的情况,说明有环
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# Definition for singly-linked list. # class ListNode(object): # def __init__(self, x): # self.val = x # self.next = None class Solution( object ): def hasCycle( self , head): """ :type head: ListNode :rtype: bool """ slow = fast = head while fast and fast. next : slow = slow. next fast = fast. next . next if fast = = slow: return True return False |
方案二:遍历链表,寻找.next=head的元素。 但超出时间限制
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# Definition for singly-linked list. # class ListNode(object): # def __init__(self, x): # self.val = x # self.next = None class Solution( object ): def hasCycle( self , head): """ :type head: ListNode :rtype: bool """ if not head: return False cur = head. next while cur: if cur. next = = head: return True cur = cur. next return False |
希望本文所述对大家Python程序设计有所帮助。
原文链接:https://blog.csdn.net/zhenghaitian/article/details/81025412