#include
    
     using namespace std;struct ListNode {	int val;	ListNode *next;	ListNode(int x) : val(x), next(NULL) {}};class Solution {public:	bool hasCycle(ListNode *head) {		if (head == NULL || head->next == NULL) //链表空或只有一个节点			return false;		ListNode* slow = head;		ListNode* fast = head;		while (fast&&fast->next){			slow = slow->next;			fast = fast->next->next;			if (slow == fast)				return true;		}		return false;	}	ListNode* createList(ListNode* head){		int numOfNode;		int value;		cout << "please input number of listNode:";		cin >> numOfNode;		cin >> value;		head = new ListNode(value);		ListNode* cur = head;		for (int i = 1; i < numOfNode; ++i){			cin >> value;			ListNode* temp = new ListNode(value);			cur->next = temp;			cur = temp;		}		//cur->next = head;		return head;	}	void printNode(ListNode* head){		ListNode* cur = head;		while (cur){			cout << cur->val << " ";			cur = cur->next;		}		cout << endl;	}};int main(){	ListNode* head = NULL;	Solution lst;	head = lst.createList(head);	//lst.printNode(head);	cout << boolalpha << lst.hasCycle(head) << endl;	system("pause");	return 0;}
    

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