using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var items = new []{"katt", "hund", "marsvin", "kanin", "kanin", "kanin", "hare", "räv", "oxe", "mus", "råtta"}.ToList();

        items = items.Select((x,n) => $"{n:D4}:{x}").ToList();

        foreach(var item in items)

            Console.WriteLine(item);

    }

}