Imports System

Public Module Module1

    Public Sub Main()

        Dim n

        dim x as integer

        x=0

        n=0

        Do

            Console.writeline("Enter a number")

            n=console.readline()

            n=n*2

            console.writeline(n)

            x=x+1

            if x = 5 then exit do

        loop until n=-1

    End Sub

End Module