Code

Function Miller(ByVal p As Long, ByVal iteration As Integer) As Boolean
        If p < 2 Then
            Return False
            Exit Function
        ElseIf p <> 2 And p Mod 2 = 0 Then
            Return False
            Exit Function
        Else

            Dim s As Long = p - 1
            While s Mod 2 = 0
                s = s / 2
            End While
            For i = 1 To iteration
                Dim a As Long = Random(1, p - 1)
                Dim temp As Long = s
                Dim Modu As Long = (a Mod temp) Mod p
                While temp <> p - 1 And Modu <> 1 And Modu <> p - 1
                    Modu = mulmod(Modu, Modu, p)
                    temp = 2 * temp
                End While
                If Modu <> p - 1 And temp Mod 2 = 0 Then
                    Return False
                    Exit Function
                End If
            Next
            Return True
        End If
    End Function

 Function mulmod(ByVal a As Long, ByVal b As Long, ByVal c As Long) As Long
        Dim x, y As Long
        x = 0
        y = a Mod c
        While b > 0
            If b Mod 2 = 1 Then
                x = (x + y) Mod c
            End If
            y = (y * 2) Mod c
            b = b / 2
        End While
        Return x Mod c

 End Function