Linked List Check For Cycle

LinkedListHasCycle.java

public class LinkedList<T> {
    
    // Reference to the head node
    Node head;
    
    public boolean hasCycle(){
        
        // check if list empty
        if(head == null) return false;
        
        // create slow and fast nodes
        Node slow, fast;
        slow = fast = head;
        
        // iterate list
        while(true){
            
            // get next node
            // slow pointer iterates the list node by node
            slow = slow.next;
            
            // check if end of the list
            if(fast.next == null) return false;
            
            // get reference of a next node always skipping one
            fast = fast.next.next;
            
            // check if end of the list
            if(fast == null) return false;
            
            // if there is a cycle then the fast and slow
            // pointers will meet at some point.
            if(fast.equals(slow)) return true;
        }
    }
    
    ...