I've been going on the Aronson Trainer site. http://aronsontrainer.altervista.org/

Great place, but one of the exercises is getting me. http://aronsontrainer.altervista.org/cha......ber.html

Preface: I am terrible at math. I can figure out a lot of these (like maybe 2/3), but depending on the positions in the deck, the same equations don't work.

Does anyone know where this ability would be useful (like which trick) so I could read what is really being asked?

What source material would have the various equations all together to solve for these?

If I knew the limits of each type of solve, it would really help.

Thank you, Mary

Hi Mary,
It looks to me like it is just asking what card you would need to cut to the face in order to bring the card C to position N.

I'm note sure if there are "various" equations. I can only think of two - cutting cards from top to bottom, or cutting cards from bottom to top.

Where it is useful is to bring a specific card to a specific position. The most obvious application is ACAAN.

You said all! Jan

I have coded this problem many times in my applications and there is a very simple algorithm that works well for computers:

k=(p-y)mod 52

Where:
k = number of cards to cut from the top and move to the bottom.
p = current position of the card (1 = top, 52 = bottom)
y = desired new position of the card (1 = top, 52 = bottom)

Example:

You want the card at position 10 to go to position 30.
k=(10-30)mod 52 = (-20)mod52 = 32

So cut 32 cards from top to bottom.
Equivalently, you could cut 52-32=20 cards from bottom to top.

This rule caters for special case when p = y, where no cut is required.

However, for humans, it's usually easier to think it this way as it only deals with positive numbers:

If p<y ? Cut y-p cards from bottom to top.
If p>y ? Cut p-y cards from top to bottom.
If p=y ? Do nothing

There are shortcuts that you could apply as well when you get familiar with the math.

This is exactly what I hoped for, Cladio.

Thank you so much.

I'll try it out tomorrow.

Yes, getting the gist of it first works best for me.

- Mary