I always start atStoney Brook when I'm looking for graphics algorithms, and of course they have a nice example of this very problem at that link. Others have already mentioned the knapsack problem but you might also want to try a search on bin packing (it seems that knowing the terminology is sometimes half the battle). I think this problem is a good candidate for a GA solution, and your particular version might be nice to try because you (probably) have only a limited set of different object dimensions to play with. I've played around with 1D bin packing several times for scheduling problems, but I have never gotten around to trying GAs, rather resorting to brute force as the problems have not been enormoous - yet. With 2D problems, you're in a whole new dimension! ;-)

I did a bit of searching and found:

• This presentation (PowerPoint I'm afraid) which looks like a nice explanation of the tabu search method applied to the knapsack problem.
• Yehoshua Perl is a researcher who seems to come up often in reference to this type of problem

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I'd like to be able to assign to an luser