using System;

using System.Linq;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        string demostr = "I AM living in Hyderabad !@#!@#$ $#$^$%&%^(^(^&(*  2130000.34 12 Q234  1!@$#!@#$ ";

        var onlychars = new String(demostr.Where(c => Char.IsLetter(c)).ToArray());

        Console.WriteLine("onlychars {0}", onlychars);

        //onlychars IAMlivinginHyderabadQ

        var onlynumbers = new String((demostr.Where(c => Char.IsNumber(c))).ToArray());

        Console.WriteLine("onlynumbers {0}",onlynumbers);

        //onlynumbers 213000034122341

        var onlydigits = new String((demostr.Where(c=> Char.IsDigit(c))).ToArray());

        Console.WriteLine("onlydigits {0}",onlydigits);

        //onlydigits 213000034122341

        var lettersandNumbers = new String((demostr.Where(c=> Char.IsLetterOrDigit(c))).ToArray());

        Console.WriteLine("lettersandNumbers {0}", lettersandNumbers);

        //lettersandNumbers IAMlivinginHyderabad21300003412Q2341

        var symbols = new String((demostr.Where(c=> Char.IsSymbol(c))).ToArray());

        Console.WriteLine("symbols {0}",symbols);

        //symbols $$$^$^^^$$

        var whitespaces = new String((demostr.Where(c=> Char.IsWhiteSpace(c))).ToArray());

        Console.WriteLine("whitespaces {0}",whitespaces.Length);

        //whitespaces 13

        var stringWithUpper =new String(demostr.Where(c => Char.IsLetter(c) && Char.IsUpper(c)).ToArray());

        Console.WriteLine("stringWithUpper {0}", stringWithUpper);

        //stringWithUpper IAMHQ

        var regexonlyLetters = Regex.Replace(demostr,@"[a-zA-Z0-9]",string.Empty);

        Console.WriteLine("regexonlyLetters {0}",regexonlyLetters);

    }

}