using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(IncrementDigits(998));

    }

    private static int IncrementDigits(int number){

        if (number == 0){

            return 0;

        }

        int lastDigit = number % 10;

        int firstDigits = number / 10;

​

        if (lastDigit == 9){

            return 10 + 100 * IncrementDigits(firstDigits);

        } else {

            return lastDigit + 1 + 10 * IncrementDigits(firstDigits);

        }

    }

}