Powerpoint 2010 VBA code randjump no repeat slides

I am trying to find a code which allows me to use a macro to jump to a random slide between a range without repeating until the end of the show. I have the code for the random jump, but I am getting repeats. This is the code I have used. I just want to know how I can adjust it to have no repeats. There are 57 slides and I want to randomize from 12 to 57.

Sub randjump () Randomize Dim Inum as Interger Inum = Int (57 * Rnd + 12) ActivePresentation.SlideShowWindow.GotoSlide (Inum) End Sub

Any help is appreciated