File: //proc/3/root/usr/lib/python2.4/Demo/scripts/queens.pyc
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=5Dc @ sD d Z d Z d f d YZ d Z e d j o e n d S( sı N queens problem.
The (well-known) problem is due to Niklaus Wirth.
This solution is inspired by Dijkstra (Structured Programming). It is
a classic recursive backtracking approach.
i t Queensc B sS t Z e d Z d Z d d Z d Z d Z d Z d Z d Z
RS( Nc C s | | _ | i d S( N( t nt selft reset( R R ( ( t) /usr/lib/python2.4/Demo/scripts/queens.pyt __init__ s c C sf | i } d g | | _ d g | | _ d g d | d | _ d g d | d | _ d | _ d S( Ni i i ( R R t Nonet yt rowt upt downt nfound( R R ( ( R R s i c C s x t | i D]p } | i | | oW | i | | | d | i j o | i n | i | d | i | | q q Wd S( Ni (
t rangeR R R t safet xt placet displayt solvet remove( R R R ( ( R R s c C s2 | i | o# | i | | o | i | | S( N( R R R R R R
( R R R ( ( R R
& s c C s@ | | i | <d | i | <d | i | | <d | i | | <d S( Ni ( R R R R R R
( R R R ( ( R R ) s
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( R R R ( ( R R / s
c C sµ | i d | _ | i o d Sn d d | i d GHxd t | i d d d D]I } d Gx7 t | i D]& } | i | | j o d Gqj d Gqj Wd GHqP Wd d | i d GHd S( Ni s +-s --t +i˙˙˙˙t |t Qt .( R R t silentR R R R ( R R R ( ( R R 7 s
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__module__t NR R R R
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c C s d k } d } t } | i d d !d g j o d } | i d =n | i d o t | i d } n t | } | | _ | i d G| i Gd GHd S( Ni i i s -nt Founds
solutions.(
t sysR R R t argvt intR t qR R ( R R R R ( ( R t mainF s
t __main__N( t __doc__R R R R ( R R R ( ( R t ?
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