[Haskell-beginners] Picking a random element from a Map
Harald Bögeholz
bo at ct.de
Wed Sep 26 09:33:26 CEST 2012
Hi,
how do I (quickly) pick a random element from a `Data.Map.Map`?
Right now I am using `head $ Map.keys p` to get the first element, but
I'd like to replace this by a random element.
I know I have to drag around the state of the random generator
somewhere, but if I have one I am wondering what's the best way to use
one to take a pick from the map.
Thanks
--
Harald Bögeholz <bo at ct.de> (PGP key available from servers)
Redaktion c't Tel.: +49 511 5352-300 Fax: +49 511 5352-417
http://www.ct.de/
int f[9814],b,c=9814,g,i;long a=1e4,d,e,h;
main(){for(;b=c,c-=14;i=printf("%04d",e+d/a),e=d%a)
while(g=--b*2)d=h*b+a*(i?f[b]:a/5),h=d/--g,f[b]=d%g;}
(Arndt/Haenel)
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