Linked List Cycle Leetcode

/**
 * 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) {
       //base case
       if(head == null || head.next == null){
           return false;
       }

       ListNode slow = head;
       ListNode fast = head;

       while(fast.next != null && fast.next.next != null){
           slow = slow.next;
           fast = fast.next.next;

           if(slow == fast){
               return true;
           }
       }
       return false;
    }
}