题解 | 判断链表中是否有环

import java.util.*;
/**
 * Definition for singly-linked list.
 * class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }
 */
public class Solution {
    public boolean hasCycle(ListNode head) {
        if (head == null || head.next == null) return false;
        for (int i = 0; i < 10000; i++)
        {
            head = head.next;
            if (head == null)
            {
                return false;
            }
        }

        return true;
    }
}