Imports System

​

Public Module Module1

​

    Public Sub Main()

        Dim TotalCount as integer

        Dim TotalDigits as integer

        Dim CreditNo as integer

        Dim CreditCount as integer

        Console.Writeline("Please enter a valid credit card number")

        CreditNo = Console.ReadLine()

        Do Until CreditNo > 10000000 and CreditNo < 99999999

            Console.Writeline("That is not a valid credit card number, please re-enter a valid number")

            CreditNo = Console.ReadLine()

        Loop

        TotalDigits = 7

        CreditCount = CreditNo

        Do

            TotalCount = TotalCount + Math.Floor(CreditCount / 10 ^ TotalDigits) 

            CreditCount = CreditCount - Math.Floor(CreditCount / 10 ^ TotalDigits) * 10 ^ TotalDigits

            TotalDigits = TotalDigits - 1

        Loop While TotalDigits > -1

        If TotalCount mod 10 = 0

            Console.Writeline(CreditNo & " is a valid credit card number.")

        Else

            Console.Writeline(CreditNo & " is not a valid credit card number.")

        End If

    End Sub

End Module