using System;

​

public class Program

{

    public static void Main()

    {

        int num, sum;

        Console.WriteLine("enter number");

        num = int.Parse(Console.ReadLine());

        sum = 0;

        while (num > 0)

        {

            sum = sum + num % 10;

            num = num/10;

        }

​

        Console.WriteLine("sum digits = " + sum);

    }

}