public class StringList {
    private Element head;

    public StringList() {}

    public String first() {}

    public void pushFront(String s) {}

    public String popFront() {}

    public boolean contains(String s) {}

    public String toString() {}

    private static class Element {
        private String s;
        private Element next;

        public Element() {}
    }

    public static void main(String[] args) {
        StringList movies = new StringList();

        movies.pushFront("Fightclub");
        movies.pushFront("Memento");
        movies.pushFront("Oldboy");
        movies.pushFront("Der Hobbit");
        movies.pushFront("Der Herr der Ringe");
        System.out.println(movies.toString());

        System.out.println(movies.contains("Memento"));
        System.out.println(movies.contains("Twilight"));
        System.out.println(movies.first());
        System.out.println(movies.popFront());
        System.out.println(movies.first());
    }
}