using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace LinkedList
{
    class Link
    {
        public Link(Product product)
        {
            Next = null;
            Prev = null;
            Product = product;
        }
        public Link Next { get; set; }
        public Link Prev { get; set; }
        public Product Product { get; set; }

        public void Unlink()
        {
            Prev.Next = Next;
            if(Next != null) Next.Prev = Prev;
        }

        public void Append(Link link)
        {
            link.Prev = this;
            Next = link;
        }

        public void Insert(Link link)
        {
            link.Prev = Prev;
            link.Next = this;
            Prev.Next = link;
            Prev = link;
        }
    }
}