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A Computer-Generated Proof that P=NP

Doron Zeilberger announced yesterday that he has proven that P=NP.

Using 3000 hours of CPU time on a CRAY machine, we settle the notorious P vs. NP problem in the affirmative, by presenting a “polynomial” time algorithm for the NP-complete subset sum problem.

The paper is available here and his 98th Opinion is offered as commentary.

zip in the point free style

Hi,

I have been recently trying to read the book algebra of programming which discusses a point free style of functional programming which can be quite appealing (via fold functions)- but there are some details which I dont quite understand yet (so far I have only gotten through the first few chapters since I had to go find a book on category theory to understand some of the terminology). The question I have is how do you do things like zip in the point free style especially if you have different fold functions for the two things you wish to zip?

Thanks in advance,

Carter.

Twitter and Scala

Thought this might be of interest to the Scala (and Twitter and Ruby on Rails) folks here. The Twitter dev team has switched to Scala because RoR couldn't handle the server side traffic. To me this is really interesting since most shops are usually hesitant to switch to "academic" languages, but here we are. And I'm pretty sure its not an April Fool's prank either!