题解 | #判断链表中是否有环#

#include <stdbool.h>
/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */

/**
 * 
 * @param head ListNode类 
 * @return bool布尔型
 */
bool hasCycle(struct ListNode* head ) {
    // write code here
    struct ListNode*list = head,*fast = head;
    while(fast&&fast->next)
    {
         list = list->next;
         fast = fast->next->next;
         if(list==fast)
         {
            return true;
         }
    }
    return false;
}