using System;

using System.Linq;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        var list = new List<int>(){1,2,42,6,7,1,10,3,25};

        var ordered = list.OrderByDescending(c=>c).Where(x=>x==10 || x == 25);

        foreach(var i in ordered){

        Console.WriteLine(i);

        }

    }

}