using System;

public class Program

{

    public static void Main()

    {

        var test = "abcd123";

        Console.WriteLine(intSum(test));

    }

    static int intSum(string s)

    {

        var sum = 0;

        for(int i=0; i < s.Length; i++)

        {

            var temp = s[i].ToString();

            if(isNumber(temp))

            {

                sum += int.Parse(temp);

            }

        }

        return sum;

    }

    static bool isNumber(string s)

    {

        int result;

        return int.TryParse(s, out result);

    }

}