diff --git a/141-linked-list-cycle/141-linked-list-cycle.py b/141-linked-list-cycle/141-linked-list-cycle.py new file mode 100644 index 0000000..e649457 --- /dev/null +++ b/141-linked-list-cycle/141-linked-list-cycle.py @@ -0,0 +1,22 @@ +# 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 head == None or head.next == None: return False + myDict = {head: 0} + point = head + while True: + point = point.next + if point == None: return False + if myDict.get(point) == None: + myDict[point] = 0 + else: + return True \ No newline at end of file