gistfile1.txt

using System;
using System.Collections.Generic;

namespace Collections4
{
    internal class Program
    {
        static void Main(string[] args)
        {
            string[] numbers1 = { "1", "2", "1" };
            string[] numbers2 = { "3", "2" };

            List<string> sortingNumbers = new List<string>();

            sortingNumbers.AddRange(numbers1);
            sortingNumbers.AddRange(numbers2);

            Console.WriteLine();

            SortNumbers(sortingNumbers);

            Console.ReadKey();
        }

        private static void SortNumbers(List<string> sortingNumbers)
        {
        Retry:

            for (int i = 0; i < sortingNumbers.Count; i++)
            {
                for (int j = i + 1; j < sortingNumbers.Count; j++)
                {
                    if (sortingNumbers[i] == sortingNumbers[j])
                    {
                        sortingNumbers.RemoveAt(j);

                        goto Retry;
                    }
                }
            }
        }
    }
}