using System;
using System.Collections.Generic;
 
public class GenericCollection
{
    public class KpopGroup
    {
        public KpopGroup(string name, string comment)
        {
            _name = name;
            _comment = comment;
        }
 
        private string _name = "";
        private string _comment = "";
 
        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }
 
        public string Comment
        {
            get { return _comment; }
            set { _comment = value; }
        }
    } // class KpopGroup
 
    public static void Main()
    {
        // Create a new LinkedList object.
        LinkedList<KpopGroup> groupList = new LinkedList<KpopGroup>();
 
        // Create KpopGroup objects to add to the linked list.
        KpopGroup g1 = new KpopGroup("BLACKPINK", "The most popular KPop female group right now. Consists of 4 members.");
        KpopGroup g2 = new KpopGroup("Kiss of Life", "Sexy vibe with amazing style. Consists of 4 members.");
        KpopGroup g3 = new KpopGroup("Stray Kids", "Write and produce their own songs. Mind-blowing music videos and dance choreography. Consists of 8 members.");
        KpopGroup g4 = new KpopGroup("BABYMONSTER", "Younger female group with monster-level talents. Consists of 7 members.");
        KpopGroup g5 = new KpopGroup("TREASURE", "Immensely talented male group that needs more promotion from their company. Consists of 10 members.");
 
        // Add the items to the linked list
        groupList.AddFirst(g1);                        // BLACKPINK
        groupList.AddFirst(g2);                        // Kiss of Life before BLACKPINK
        groupList.AddBefore(groupList.Find(g1), g3);   // Stray Kids before BLACKPINK
        groupList.AddAfter(groupList.Find(g1), g4);    // BABYMONSTER after BLACKPINK
        groupList.AddLast(g5);                         // TREASURE at the end
 
        Console.WriteLine("\nMy Favorite KPop Groups and Their Comments:\n");
 
        // Display all items
        foreach (KpopGroup grp in groupList)
        {
            Console.WriteLine(grp.Name + " : " + grp.Comment);
        }
 
        Console.WriteLine("\nDisplaying the second group in the ranking:\n");
        Console.WriteLine("groupList.First.Next.Value.Name == " +
                          groupList.First.Next.Value.Name);
 
        Console.WriteLine("\nDisplaying the next-to-last group in the ranking:\n");
        Console.WriteLine("groupList.Last.Previous.Value.Name == " +
                          groupList.Last.Previous.Value.Name);
    }
}

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