Problem: 141. 环形链表
时间复杂度:
O
(
n
)
O(n)
O(n)
空间复杂度:
O
(
1
)
O(1)
O(1)
/**
* Definition for singly-linked list.
* class ListNode {
* int val;
* ListNode next;
* ListNode(int x) {
* val = x;
* next = null;
* }
* }
*/
public class Solution {
public boolean hasCycle(ListNode head)
{
int cnt = 0;
ListNode slow = head;
ListNode fast = head;
while (fast != null)
{
fast = fast.next;
if (fast != null)
fast = fast.next;
if (fast == slow)
return true;
slow = slow.next;
}
return false;
}
}
时间复杂度:
O
(
n
)
O(n)
O(n)
空间复杂度:
O
(
1
)
O(1)
O(1)
/**
* Definition for singly-linked list.
* class ListNode {
* int val;
* ListNode next;
* ListNode(int x) {
* val = x;
* next = null;
* }
* }
*/
public class Solution {
public boolean hasCycle(ListNode head)
{
if(head == null)
return false;
int cnt = 0;
while (cnt < 10000)
{
cnt++;
if (head.next == null)
return false;
head = head.next;
}
return true;
}
}