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Old March 3rd, 2004, 04:43 AM

mlepinski mlepinski is offline
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Default Re: Better, Simpler Programming Contest

Quote:
Originally posted by PhilD:
Let's nitpick a little: just saying the problem is NP does not mean no good solution is known. Every P problem is also NP. What you're thinking of, most likely, is NP-complete.

And yes, I do teach CS, rather on the theoretical side
Thanks Phil, this was also my first reaction when I read Saber Cherry's original post. (I have also taught thoery of computer science).

Which raises the question: Is the problem that Saber Cherry posed NP-Complete?

It's clear to me that the problem is NP-Complete if you allow an arbitrary number of resource types (instead of only 3 - gold, resources and holy) or if you restrict so that you are limited to building at most one copy of each unit in a single turn.(which makes no sense in the context of Dominions where I often want to build many lowbowmen each turn). (Note: In either of these cases there is a simple reduction to subset sum.) However, it is unclear to me whether the specific Dominions-inspired problem (with exactly three resources and the ability to buy many copies of the same unit) is NP-Complete.

- Matt Lepinski :->

[ March 03, 2004, 02:45: Message edited by: mlepinski ]
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