Imports System

Public Module Module1

    Public Sub Main()

        Divisible()

    End Sub

    Sub Fibonacci()

            Dim f1 as integer = 1

            Dim f2 as integer = 1

            Dim f as integer

            Dim even as integer

            Do until f>4000000

                f = f1 + f2

                f1 = f2

                f2 = f

                If f mod 2 = 0 Then

                    even = even + f

                End If

            Loop

            Console.WriteLine(even)

    End Sub

    Sub Prime()

        Dim n as double = 600851475143

        Dim i as integer

        Dim j as integer

        Dim prime as boolean = true

        Dim large as integer

        For i = 1 to Math.Ceiling(Math.sqrt(n))

        If n mod i = 0

            For j = 2 to i-1

            If i mod j = 0 then

                prime = false

            End If

        Next

        If prime = true then

            large = i

        End If

    End If

        Next

​

Console.WriteLine (large)

    End Sub

End Module