using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public class ListItem

    {

        public string Item { get; set; }

    }

    public static List<ListItem> getSortedList()

    {

        int dummy = 0;

        List<ListItem> list = new List<ListItem>();

        list.Add(new ListItem() { Item = "A" });

        list.Add(new ListItem() { Item = "B" });

        list.Add(new ListItem() { Item = "C" });

        list.Add(new ListItem() { Item = "111" });

        list.Add(new ListItem() { Item = "11" });

        list.Add(new ListItem() { Item = "123" });

        list.Add(new ListItem() { Item = "1" });

        list.Add(new ListItem() { Item = "42" });

        list.Add(new ListItem() { Item = "5" });

        var listNumber = list.Where(m => int.TryParse(m.Item, out dummy)).ToList().OrderBy(m => Convert.ToInt16(m.Item)).ToList();

        var listString = list.Where(m => !int.TryParse(m.Item, out dummy)).ToList().OrderBy(m => m.Item).ToList();

        var sortedList = listNumber.Concat(listString).ToList();

        return sortedList;

    }

    public static void Main()

    {

        foreach(ListItem item in getSortedList()){

            Console.WriteLine(item.Item);

        }

    }

}