using System;

public class Program

{

    public static void Main()

    { 

        string strNumber ="100TG";

        int Result = 0;

        bool isConversionSuccessful = int.TryParse(strNumber, out Result);

        if (isConversionSuccessful)

        {

          Console.WriteLine(Result);

        }

        else

        {

          Console.WriteLine("Please enter avalid Number");

        }

    }

}