with a secondary constructor, how can i find the size with only a head and tail nodes, from previous testing there is a way to make the size 3 in this secondaey constructor

LinkedList IU Qsages private NodeDL tail; 11 usages private int size; I/ TOD0: default constructor 8 usages public DoublyLinkedList()\{ this (head: null, tail: null); this. size = 0; // TODo: secondary constructor 4 usages public DoublyLinkedList (NodeDL head, NodeDL tail) this.head = head; this.tail = tail; \}