using System;

using System.Collections.Generic;

using System.Linq;

​

namespace ConsoleApp1

{

    class Program

    {

        static void Main(string[] args)

        {

            var list = new List<int>() { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

            var sorted = SortMinMax(list);

            foreach (var i in sorted) Console.WriteLine(i);

        }

        private static List<int> SortMinMax(List<int> _list)

        {

            var list = _list.OrderBy(q => q).ToList();

            var resultlist = new List<int>();

            while (list.Any())

            {

                var first = list.First();

                resultlist.Add(first);

                list.Remove(first);

                if (list.Any())

                {

                    var last = list.LastOrDefault();

                    resultlist.Add(last);

                    list.Remove(last);

                }

            }

​

            return resultlist.ToList();

        }

    }

}

​