typedef struct listNode {
int val;
struct listNode *next;
} listNode;
bool hasCycle(struct ListNode *head) {
if (head == NULL) return false;
listNode *fast = head->next, *slow = head;
while (fast != NULL && fast->next != NULL && fast->next->next != NULL) {
if (fast == slow) {
return true;
}
fast = fast->next->next;
slow = slow->next;
}
return false;
}
暂无评论