Module Module1
    ' program fibonacci.py
    ' recursive algorithm to calculate the numbers in the
    ' Fibonacci sequence 0,1,1,2,3,5,8..
    ' in which each number after the first two
    ' is the sum of the previous pair of numbers
    ' each routine is timed

    ' Fibonacci recursive method
    Function fibRecursive(ByVal inNum)
        If (inNum = 0) Then
            Return (0)
        ElseIf (inNum = 1) Then
            Return (1)
        Else
            Return (fibRecursive(inNum - 1) + fibRecursive(inNum - 2))
        End If
    End Function

    ' Fibonacci iterative method
    Function fibIterative(ByVal inNum) As List(Of Integer)
        Dim i As Integer
        ' list of first two Fibonacci numbers
        Dim fibNumbers = New List(Of Integer) From {0, 1}

        ' now append the sum of the two previos numbers to the list    
        For i = 2 To (inNum - 1)
            fibNumbers.Add(fibNumbers(i - 1) + fibNumbers(i - 2))
        Next
        Return fibNumbers
    End Function


    Sub Main()
        Dim seriesLen As Integer = 0
        Dim i As Integer = 0
        Dim eat As String = ""
        Dim newFibList As List(Of Integer)
        Dim num As Integer = 0


        Try
            Console.WriteLine("Select a number in the range of 3 to 30 to be the length of the fibonacci series")
            seriesLen = Console.ReadLine()

            Console.WriteLine("Recursive method")
            For i = 0 To (seriesLen - 1)
                Console.WriteLine(String.Format("{0} {1}", i + 1, fibRecursive(i)))
            Next

            Console.WriteLine("")
            Console.WriteLine("Iterative method")
            newFibList = fibIterative(seriesLen)

            i = 0
            For Each num In newFibList
                Console.WriteLine(String.Format("{0} {1}", i + 1, num))
                i = i + 1
            Next

        Catch ex As Exception
            Console.WriteLine("Please enter a number in the range of 3 and 30 inclusive.")
        End Try

        Console.WriteLine("Any key to continue")
        eat = Console.ReadLine()
    End Sub

End Module