using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        List<string> myList = new List<string>() 

        {

        "AS2258B43C014AI9954803",

        "AS2258B43C014AI9954603",

        "AS2258B43C014AI9954703",

        "AS2258B43C014AI9954503",

        "AS2258B43C014AI9954403",

        "AS2258B43C014AI9954203",

        "AS2258B43C014AI9954303",

        "AS2258B43C014AI9954103",

        };

        string first = myList[0];

        string result = first + "/" + string.Join("/", myList.Skip(1).Select(x => GetDiff(first,x)));

        Console.WriteLine(result);

    }

    private static string GetDiff (string s1, string s2)

    {

        int i;

        for(i = 0; i < Math.Min(s1.Length,s2.Length); i++)

        {

            if(s1[i] != s2[i])

            {

                break;

            }

        }

        return s2.Substring(i);

    }

}