Imports System

​

Public Module Module1

    Public Sub Main()

        Dim Input As ULong

        Console.Write("Enter a number: ")

        Input = Convert.ToUInt64(Console.ReadLine())

        Console.WriteLine(FormatNumber(Input))

    End Sub

​

    Public Function FormatNumber(ByVal Input As ULong) As String

        Dim Result As String = Input.ToString()

​

        If Input >= 1000000000

            Result = String.Format("{0}b", Input / 1000000000) 

        Else If Input >= 1000000

            Result = String.Format("{0}m", Input / 1000000)

        Else If Input > 1000

            Result = String.Format("{0}k", Input / 1000)

        End If

​

        Return Result

    End Function

End Module