public static void main(String args[]) throws IOException { Scanner sc = new Scanner(System.in); LinkedList6 l1 = new LinkedList6(); System.out.println("populate linkedlist1 with integers"); int i = 0; while (true) { i++; System.out.println("enter integer value of node" + i + " or enter -1 to exit"); int num = sc.nextInt(); if (num == -1) break; l1.insert(num); } LinkedList6 l2 = new LinkedList6(); System.out.println("populate linkedlist2 with integers"); i = 0; while (true) { i++; System.out.println("enter integer value of node" + i + " or enter -1 to exit"); int num = sc.nextInt(); if (num == -1) break; l2.insert(num); } System.out.println("when L1 and L2 do not intersect:"); l1.display(); l2.display(); if (l1.isIntersecting(l2)) System.out.println("L1 and L2 intersect!"); else System.out.println("L1 and L2 do not intersect!"); // creating an intersection to check whether the isIntersecting() function works. Random r = new Random(); // appending l2 to l1 randomly int ref = r.nextInt(l1.numNodes() + 1); Node6 reference = l1.getReference(ref); l2.makeIntersect( reference); // l2 is appended to l1 at the reference node returned by getReference() l2.display(); if (l1.isIntersecting(l2)) System.out.println("L1 and L2 intersect!"); else System.out.println("L1 and L2 do not intersect!"); }