data structures (postfix/prefix)

Hi...

I'm having a few problems with the book that I

have regarding prefix and postfix portion of

data structures. I was wondering if anyone knew

of a web site that might have a few examples that

I could learn from.

Maybe someone can tell me if I'm right or wrong:

prob: Translate each of the following expressions from prefix to postfix:

a) / + x y ! n (prefix)

x y + / n ! (my answer in postfix)

b) / + ! x y n (prefix)

x y + / n ! (my answer in postfix)

These are my results, I'm just looking to see if I am doing this right.