Imports System

Imports Microsoft.VisualBasic.Conversion

Public Module Module1

    Public Sub Main()

        Dim sum as Integer = 0

        Dim n, num as Integer

        Console.writeline("Write a number")

        num = Console.readline()

        do

            n = num mod 10

            sum = sum + n

            num = Int(num/10)

        loop until num = 0

        console.WriteLine(sum)

    End Sub

End Module