Imports System

Public Module Module1

    Public Sub Main()

        DIM unit as integer

        DIM bill as integer 

        Console.WriteLine("Enter your total units.")

        unit=Console.ReadLine()

        if unit<0 then 

            Console.WriteLine("You have entered invalid units.")

        else if unit>0 and unit<=100 then 

            bill =(unit*13) 

            Console.WriteLine("Your bill is Rs. " & bill & "/-") 

        elseif unit>100 and unit<=300 then

            bill=(1300+((unit-100)*20))

            Console.WriteLine("Your bill is Rs. " & bill & "/-") 

        elseif unit>300 then

            bill= (1300+4000+((unit-300)*30))

            Console.WriteLine("Your bill is Rs. " & bill & "/-") 

        end if

    End Sub

End Module