mycode 98.22%
# 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 or not head.next: return False fast = slow = head while fast.next and fast.next.next: slow = slow.next fast = fast.next.next if slow == fast: return True return False
参考
可以稍微简化一丢丢
# 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 slow == fast: return True return False