Junior White <efiish@gmail.com> ÐÉÓÁÌ(Á) × Ó×Ï£Í ÐÉÓØÍÅ Tue, 29 Jan 2013 12:25:49 +0300:

The only different in the two program is in the first is "q <- [1..n], qs
<- queens' (k-1)," and the second is "qs <- queens' (k-1), q <- [1..n]".

In the first case `queens' (k-1)` is being recomputed for every q (that is, n times). Of course it would matter :)

_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe