Imports System

Public Module Module1

    Public Sub Main()

        Dim input as integer

        Dim tries as integer

        Dim output as integer

        tries = 0

        Do While input <> -1

            If tries <= 5

                Console.Writeline("Please enter a number")

                input = Console.Readline()

                output = input*2

                Console.Writeline(output)

                tries += 1

            Else

                Console.Writeline("You have no more chance now")

            End if

        Loop 

        Console.Writeline("Loop ended")

    End Sub

End Module