LeetCode: Circular Linked List

Table of contents

topic

example

train of thought

the code

appendix

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topic

Give you the head node head of a linked list, and judge whether there is a ring in the linked list.

If there is a node in the linked list that can be reached again by continuously tracking the next pointer, then there is a cycle in the linked list. In order to represent the ring in the given linked list, the evaluation system internally uses the integer pos to indicate the position where the end of the linked list is connected to the linked list (the index starts from 0). Note: pos is not passed as a parameter. Just to identify the actual situation of the linked list.

Returns true if there is a cycle in the linked list. Otherwise, returns false.

example

Example 1:

input: hea