题解 | #判断链表中是否有环#

/**
 * 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) {
        int  crazy_max=10000;
        if(head==NULL)return false;
        for(;crazy_max!=0;crazy_max--)
       {
        if (head->next== NULL )return false;
        else head=head->next;
       } 
       return true;
    }
};