N-Queen Problem: Python 2.6.5 vs PyPy 1.5.0

Re:N-Queen Problem: Python 2.6.5 vs PyPy 1.5.0 by reinhardt on Sunday May 29, 2011 @04:18PM (#2597485)

"...all N-Queen problem comes to mere 8 lines of code"

If you are optimizing in LOC, it can come down to basically a single expression; of course that's not a reason to write it as a one-liner:

    def n_queen(n):
        return (p for p in itertools.permutations(xrange(n))
                if all(j-i != abs(p[i] - p[j])
                       for i in xrange(n - 1)
                       for j in xrange(i + 1, n)))

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Re:N-Queen Problem: Python 2.6.5 vs PyPy 1.5.0 by beagle3 on Sunday May 29, 2011 @07:49PM (#2597947)

If you are optimizing for LOC, use a suitable language:

from http://nsl.com/papers/qn.htm , the code that computes the solution is

  qn:{[n],/{:[n=#*x;,*x;,/_f'f x,\:/:(!n)_dvl,/x]}'(f:0 -1 1+/:)@!n}

And it uses backtracking, which makes it infinitely faster.

But armin isn't optimizing LOC.

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