02.09.03.01.NineGagNumbers

using System;
using System.Text;

class NineGagNumbers
{
    static string ConvertToDigits(string input)
    {
        StringBuilder sbNumb = new StringBuilder();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < input.Length; i++)
        {
            sb.Append(input[i]);
            string temp = sb.ToString();
            if (temp == "-!")
            {
                sb.Remove(0, 2);
                sbNumb.Append(0);
            }
            else if (temp == "**")
            {
                sb.Remove(0, 2);
                sbNumb.Append(1);
            }
            else if (temp == "!!!")
            {
                sb.Remove(0, 3);
                sbNumb.Append(2);
            }
            else if (temp == "&&")
            {
                sb.Remove(0, 2);
                sbNumb.Append(3);
            }
            else if (temp == "&-")
            {
                sb.Remove(0, 2);
                sbNumb.Append(4);
            }
            else if (temp == "!-")
            {
                sb.Remove(0, 2);
                sbNumb.Append(5);
            }
            else if (temp == "*!!!")
            {
                sb.Remove(0, 4);
                sbNumb.Append(6);
            }
            else if (temp == "&*!")
            {
                sb.Remove(0, 3);
                sbNumb.Append(7);
            }
            else if (temp == "!!**!-")
            {
                sb.Remove(0, 6);
                sbNumb.Append(8);
            }
        }

        string nineGagString = sbNumb.ToString();
        return nineGagString;
    }

    static decimal ConvertToDecimal(string nineGagString)
    {
        decimal decimalNumber = 0;
        int counter = 0;
        for (int i = nineGagString.Length - 1; i >= 0; i--)
        {
            int currentDigit = (int)(nineGagString[i]) - 48;
            decimalNumber = decimalNumber + ((decimal)currentDigit * Pow(9, counter));
            counter++;
        }
        return decimalNumber;
    }

    static decimal Pow(int baseNumb, int counter)
    {
        decimal powerNumber = 1;
        for (int i = 0; i < counter; i++)
        {
            powerNumber = powerNumber * baseNumb;
        }
        return powerNumber;
    }

    static void Main()
    {
        string input = Console.ReadLine(); //"*!!!";

        // first translate the symbols to digits
        string numberInNineGag = ConvertToDigits(input);

        // second convert the number from 9 numrical system to 10 ns
        decimal numberInDecimal = ConvertToDecimal(numberInNineGag);
        Console.WriteLine(numberInDecimal);
    }
}