[leetcode]141. Linked List Cycle@Java解题报告

https://leetcode.com/problems/linked-list-cycle/discuss/

Given a linked list, determine if it has a cycle in it.

Follow up:
Can you solve it without using extra space?

package go.jacob.day818;public class Demo1 {/* * 建立slow和fast两个指针，fast一次移动两格，slow移动一格，如果fast==slow说明存在环 */public boolean hasCycle(ListNode head) {if (head == null)return false;ListNode slow = head;ListNode fast = head;while (fast.next != null && fast.next.next != null) {slow = slow.next;fast = fast.next.next;if (slow == fast)return true;}return false;}}