141. Linked List Cycle
Given a linked list, determine if it has a cycle in it.
Follow up:
Can you solve it without using extra space?
public class Solution {
public boolean hasCycle(ListNode head) {
if (head == null) {
return false;
}
ListNode slow = head;
ListNode fast = head;
while (fast != null && fast.next != null) {
slow = slow.next;
fast = fast.next.next;
if (fast == slow) {
return true;
}
}
return false;
}
}
更多精彩
