using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(AreAnagrams("listen","silent"));

        Console.WriteLine(AreAnagrams("rat","car"));

    }

        static bool AreAnagrams(string s1,string s2)

        {

            string str1=new string(s1.Where(c=>Char.IsLetter(c)).ToArray()).ToLower();

            string str2=new string(s2.Where(c=>Char.IsLetter(c)).ToArray()).ToLower();

            return String.Concat(str1.OrderBy(c=>c))==String.Concat(str2.OrderBy(c=>c));

        }

}

​