UniqueFloydAlgorithmpo.java

public class UniqueFloydAlgorithm {

    public static void main(String[] args) {
        ListNode head = new ListNode(3);
        head.next = new ListNode(2);
        head.next.next = new ListNode(0);
        head.next.next.next = new ListNode(-4);
        // Create cycle
        head.next.next.next.next = head.next;
        boolean hasCycle = hasCycle(head);
        if (hasCycle) {
            System.out.println("The linked list has a cycle.");
        } else {
            System.out.println("The linked list does not have a cycle.");
        }
    }

    public static boolean hasCycle(ListNode head) {
        if (head == null || head.next == null) {
            return false;
        }
        ListNode slow = head;
        ListNode fast = head.next;
        while (slow != fast) {
            if (fast == null || fast.next == null) {
                return false;
            }
            slow = slow.next;
            fast = fast.next.next;
        }
        return true;
    }
}
class ListNode {
    int val;
    ListNode next;

    ListNode(int x) {
        val = x;
        next = null;
    }
}