

Dancing Links (A very useful hack by Knuth) - mahmud
http://en.wikipedia.org/wiki/Dancing_Links

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slackenerny
Cool, this.

A very nifty (if somewhat detailed) complexity analysis of the Algorithm X
appeared in blogosphere's festschrift for Knuth's 70,
<http://11011110.livejournal.com/128249.html>

I've used P159 in my absolutely first assignment in the intro programming
class. I was to make a N-queens solver. The assignment obviously asked for a
8-line backtracking program. But I was naïve. I went to the library and turned
it inside out. My solution was ca. 500 lines, and also implemented a way to
find the number of solutions without computing them (this was from IIRC a
paper by Rivin), and had a randomized mode which would find just a single
solution but for fast for very large N (this I found in Norvig's AIMA in a
footnote referencing a paper by J.M., I don't remember the page or the full
name)). Good times.

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mullr
Maybe it's obvious to some, but not to me: what are some applications of
algorithm X?

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mahmud
I am using it for GUI layout management. jquery based. still hacking on it
though.

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eclark
How are you coming up with the constraints and what fills what needs ?

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d_c
I saw this here earlier.

