题解 | #判断链表中是否有环#
判断链表中是否有环
https://www.nowcoder.com/practice/650474f313294468a4ded3ce0f7898b9
借助Set
public class Solution {
public boolean hasCycle(ListNode head) {Set<ListNode> set = new HashSet<>();
while(head != null){
if(set.contains(head)){
return true;
}
set.add(head);
head = head.next;
}
return false;
}
}
