namespace _29
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Introduceti numarul in sistem hexazecimal");
            char[] decimalNumberArray = Console.ReadLine().ToCharArray();
           
            int digit;
            double pr = 0, sum = 0;
            int p = 0;

            //parcurgem vectorul de la ultima la prima cifra            
            for (int i = decimalNumberArray.Length - 1; i >= 0; i--)
            {
                //verificam daca este numar
                if (int.TryParse(decimalNumberArray[i].ToString(), out digit))
                {
                    pr = digit * Math.Pow(16, p);
                }
                //transformam conform codului ASCII
                else
                {
                    if (((char)decimalNumberArray[i] >= 65) && ((char)decimalNumberArray[i] <= 70))
                        pr = (decimalNumberArray[i] - 55) * Math.Pow(16, p);
                }

                p++;
                sum += pr;
            }
            
            Console.WriteLine(sum.ToString());

            Console.ReadLine();
        }
    }
}