Question

Im having trouble in my main class here and I’m trying to add new item, remove , find and display in my list, and I have tried everything with a scanner and it seems to not work..this is my code so far and what I have done…how would I be able to do it ?

  import java.util.*;
  import java.util.LinkedList;

    public class Main {
public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    SinglyLinkedList<String> names = new SinglyLinkedList<String>();
    names.add("Fred");
    names.add("Earl");
    names.add("Dan");
    names.add("Carl");
    names.add("Ben");

    System.out.println(names);



    System.out.println("Add an item");
    System.out.println("" + input.nextLine());
    names.add();
    System.out.println("LinkedList:" + names);

    System.out.println("Remove an item");
    System.out.println("" + input.nextLine());
    names.remove();
    System.out.println("LinkedList:" + names);


    System.out.println("Find an item");
    System.out.println("" + input.nextLine());
    names.findFirst(element);
    System.out.println("LinkedList:" + names);


    System.out.println("Display an list");
    System.out.println("LinkedList:" + names);

    System.out.println("Exit");
    input.close();


}

 }

Answer 1

You’re not actually adding or removing anything to your LinkedList because you never pass any arguments to the add and remove methods. Try something like this:

System.out.println("Add an item");
names.add(input.nextLine());
System.out.println("LinkedList: " + names);

System.out.println("Remove an item");
names.remove(input.nextLine());
System.out.println("LinkedList: " + names);


System.out.println("Find an item");
names.findFirst(input.nextLine());
System.out.println("LinkedList: " + names);