jiamo

module Cartesian_product2 where 
import Prelude hiding(product)

-- introduce mapa
map' :: (b->a) -> [b] -> [a]
map' g l = foldr' f [] l where
    f x y = (g x) : y

foldr' :: (a -> b -> b) -> b -> [a] -> b
foldr' f z [] = z

jiamo

module Cartesian_product1 where
import Prelude hiding(product)
 
product1 [] = [[]]
product1 (xs:xss) = 
  h xs (product1 xss) where
    h [] xss = []
    h (x : xs) xss =
      map (x:) xss ++ h xs xss
      

jiamo

cd ~/

apt-get install git automake autoconf libtool pkg-config make g++ zlib1g-dev libcurl4-gnutls-dev
git clone https://github.com/MediaArea/ZenLib.git
git checkout v0.4.37
cd ZenLib/Project/GNU/Library
./autogen.sh
./configure --enable-static
make -j4