using System;
using System.Collections.Generic;
using System.Linq;

namespace School_Library
{
    class Program
    {
        static void Main(string[] args)
        {
            List<string> books = Console.ReadLine().Split("&").ToList();

            string input = Console.ReadLine();
            while (input != "Done")
            {
                string[] tokens = input.Split(" | ");
                string command = tokens[0];

                if (command == "Add Book")
                {
                    string book = tokens[1];
                    if (!books.Contains(book))
                    {
                        books.Insert(0, book);
                    }
                }
                else if (command == "Take Book")
                {
                    string book = tokens[1];
                    if (books.Contains(book))
                    {
                        books.Remove(book);
                    }
                }
                else if (command == "Swap Books")
                {
                    string firstBook = tokens[1];
                    string secondBook = tokens[2];
                    if (books.Contains(firstBook) && books.Contains(secondBook))
                    {
                        int index1 = books.IndexOf(firstBook);
                        int index2 = books.IndexOf(secondBook);
                        string temp = firstBook;
                        books[index1] = books[index2];
                        books[index2] = temp;
                    }
                }
                else if (command == "Insert Book")
                {
                    string book = tokens[1];
                    books.Add(book);
                }
                else if (command == "Check Book")
                {
                    int index = int.Parse(tokens[1]);
                    if (index >= 0 && index < books.Count)
                    {
                        Console.WriteLine(books[index]);
                    }
                }

                input = Console.ReadLine();
            }

            Console.WriteLine(String.Join(", ", books));
        }
    }
}