Given a linked list, determine if it has a cycle in it.
Follow up:
Can you solve it without using extra space?
这个是用快慢指针,记得边界条件的判断就行了。
/** * Definition for singly-linked list. * class ListNode { * int val; * ListNode next; * ListNode(int x) { * val = x; * next = null; * } * } */ // 16:48->16:51 pass public class Solution { public boolean hasCycle(ListNode head) { ListNode n1,n2; n1 = n2 = head; if(head==null) { return false; } while(true) { if(n2==null || n2.next==null) { break; }else { n2 = n2.next.next; } n1 = n1.next; if(n1==n2) { return true; } } return false; } }
Linked List Cycle,布布扣,bubuko.com
原文地址:http://blog.csdn.net/nan327347465/article/details/38339179