#Leetcode# 141. Linked List Cycle
https://leetcode.com/problems/linked-list-cycle/
Given a linked list, determine if it has a cycle in it.
Follow up:
Can you solve it without using extra space?
Accepted
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Submissions
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Seen this question in a real interview before?
代码:
/** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode(int x) : val(x), next(NULL) {} * }; */ class Solution { public: bool hasCycle(ListNode *head) { ListNode *slow = head, *fast = head; while (fast && fast->next) { slow = slow->next; fast = fast->next->next; if (slow == fast) return true; } return false; } };
快慢指针 如果是个环的话那么快慢指针一定会遇到! 第一次遇到快慢指针的问题居然是在链表里 毕竟链表我还没看很懂啊