Para la determinaci\u00f3n de las alergia se utiliza los siguientes c\u00f3digos para los al\u00e9rgenos:<\/p>\n
\n Huevos ........ 1\n Cacahuetes .... 2\n Mariscos ...... 4\n Fresas ........ 8\n Tomates ....... 16\n Chocolate ..... 32\n Polen ......... 64\n Gatos ......... 128\n<\/pre>\nAs\u00ed, si Juan es al\u00e9rgico a los cacahuetes y al chocolate, su puntuaci\u00f3n es 34 (es decir, 2+32).<\/p>\n
Los al\u00e9rgenos se representan mediante el siguiente tipo de dato<\/p>\n
\n data Alergeno = Huevos\n | Cacahuetes\n | Mariscos\n | Fresas\n | Tomates\n | Chocolate\n | Polen\n | Gatos\n deriving (Enum, Eq, Show, Bounded)\n<\/pre>\nDefinir la funci\u00f3n<\/p>\n
\n alergias :: Int -> [Alergeno]\n<\/pre>\ntal que (alergias n) es la lista de alergias correspondiente a una puntuaci\u00f3n n. Por ejemplo,<\/p>\n
\n \u03bb> alergias 1\n [Huevos]\n \u03bb> alergias 2\n [Cacahuetes]\n \u03bb> alergias 3\n [Huevos,Cacahuetes]\n \u03bb> alergias 5\n [Huevos,Mariscos]\n \u03bb> alergias 255\n [Huevos,Cacahuetes,Mariscos,Fresas,Tomates,Chocolate,Polen,Gatos]\n<\/pre>\nSoluciones<\/h4>\n
[schedule expon=’2022-04-18′ expat=\u00bb06:00″]<\/p>\n
[\/schedule]<\/p>\n
[schedule on=’2022-04-18′ at=\u00bb06:00″]<\/p>\n
\r\nimport Data.List (subsequences)\r\nimport Test.QuickCheck\r\n\r\ndata Alergeno =\r\n Huevos\r\n | Cacahuetes\r\n | Mariscos\r\n | Fresas\r\n | Tomates\r\n | Chocolate\r\n | Polen\r\n | Gatos\r\n deriving (Enum, Eq, Show, Bounded)\r\n\r\n-- 1\u00aa soluci\u00f3n\r\n-- ===========\r\n\r\nalergias1 :: Int -> [Alergeno]\r\nalergias1 n =\r\n [a | (a,c) <- zip alergenos codigos, c `elem` descomposicion n]\r\n\r\n-- codigos es la lista de los c\u00f3digos de los alergenos.\r\ncodigos :: [Int]\r\ncodigos = [2^x| x <- [0..7]]\r\n\r\n-- (descomposicion n) es la descomposici\u00f3n de n como sumas de potencias\r\n-- de 2. Por ejemplo,\r\n-- descomposicion 3 == [1,2]\r\n-- descomposicion 5 == [1,4]\r\n-- descomposicion 248 == [8,16,32,64,128]\r\n-- descomposicion 255 == [1,2,4,8,16,32,64,128]\r\ndescomposicion :: Int -> [Int]\r\ndescomposicion n =\r\n head [xs | xs <- subsequences codigos, sum xs == n]\r\n\r\n-- 2\u00aa soluci\u00f3n\r\n-- ===========\r\n\r\nalergias2 :: Int -> [Alergeno]\r\nalergias2 = map toEnum . codigosAlergias\r\n\r\n-- (codigosAlergias n) es la lista de c\u00f3digos de alergias\r\n-- correspondiente a una puntuaci\u00f3n n. Por ejemplo,\r\n-- codigosAlergias 1 == [0]\r\n-- codigosAlergias 2 == [1]\r\n-- codigosAlergias 3 == [0,1]\r\n-- codigosAlergias 4 == [2]\r\n-- codigosAlergias 5 == [0,2]\r\n-- codigosAlergias 6 == [1,2]\r\ncodigosAlergias :: Int -> [Int]\r\ncodigosAlergias = aux [0..7]\r\n where aux [] _ = []\r\n aux (x:xs) n | odd n = x : aux xs (n `div` 2)\r\n | otherwise = aux xs (n `div` 2)\r\n\r\n-- 3\u00aa soluci\u00f3n\r\n-- ===========\r\n\r\nalergias3 :: Int -> [Alergeno]\r\nalergias3 = map toEnum . codigosAlergias3\r\n\r\ncodigosAlergias3 :: Int -> [Int]\r\ncodigosAlergias3 n =\r\n [x | (x,y) <- zip [0..7] (int2bin n), y == 1]\r\n\r\n-- (int2bin n) es la representaci\u00f3n binaria del n\u00famero n. Por ejemplo,\r\n-- int2bin 10 == [0,1,0,1]\r\n-- ya que 10 = 0*1 + 1*2 + 0*4 + 1*8\r\nint2bin :: Int -> [Int]\r\nint2bin n | n < 2 = [n]\r\n | otherwise = n `rem` 2 : int2bin (n `div` 2)\r\n\r\n-- 4\u00aa soluci\u00f3n\r\n-- ===========\r\n\r\nalergias4 :: Int -> [Alergeno]\r\nalergias4 = map toEnum . codigosAlergias4\r\n\r\ncodigosAlergias4 :: Int -> [Int]\r\ncodigosAlergias4 n =\r\n map fst (filter ((== 1) . snd) (zip [0..7] (int2bin n)))\r\n\r\n-- 5\u00aa soluci\u00f3n\r\n-- ===========\r\n\r\nalergias5 :: Int -> [Alergeno]\r\nalergias5 = map (toEnum . fst)\r\n . filter ((1 ==) . snd)\r\n . zip [0..7]\r\n . int2bin\r\n\r\n-- 6\u00aa soluci\u00f3n\r\n-- ===========\r\n\r\nalergias6 :: Int -> [Alergeno]\r\nalergias6 = aux alergenos\r\n where aux [] _ = []\r\n aux (x:xs) n | odd n = x : aux xs (n `div` 2)\r\n | otherwise = aux xs (n `div` 2)\r\n\r\n-- alergenos es la lista de los alergenos. Por ejemplo.\r\n-- take 3 alergenos == [Huevos,Cacahuetes,Mariscos]\r\nalergenos :: [Alergeno]\r\nalergenos = [minBound..maxBound]\r\n\r\n-- Comprobaci\u00f3n de equivalencia\r\n-- ============================\r\n\r\n-- La propiedad es\r\nprop_alergias :: Property\r\nprop_alergias =\r\n forAll (arbitrary `suchThat` esValido) $ \\n ->\r\n all (== alergias1 n)\r\n [alergias2 n,\r\n alergias3 n,\r\n alergias4 n,\r\n alergias5 n,\r\n alergias6 n]\r\n where esValido x = 1 <= x && x <= 255\r\n\r\n-- La comprobaci\u00f3n es\r\n-- \u03bb> quickCheck prop_alergias\r\n-- +++ OK, passed 100 tests.\r\n\r\n-- Comparaci\u00f3n de eficiencia\r\n-- =========================\r\n\r\n-- La comparaci\u00f3n es\r\n-- \u03bb> last (map alergias1 [1..255])\r\n-- [Huevos,Cacahuetes,Mariscos,Fresas,Tomates,Chocolate,Polen,Gatos]\r\n-- (0.02 secs, 1,657,912 bytes)\r\n-- \u03bb> last (map alergias2 [1..255])\r\n-- [Huevos,Cacahuetes,Mariscos,Fresas,Tomates,Chocolate,Polen,Gatos]\r\n-- (0.01 secs, 597,080 bytes)\r\n-- \u03bb> last (map alergias3 [1..255])\r\n-- [Huevos,Cacahuetes,Mariscos,Fresas,Tomates,Chocolate,Polen,Gatos]\r\n-- (0.01 secs, 597,640 bytes)\r\n-- \u03bb> last (map alergias4 [1..255])\r\n-- [Huevos,Cacahuetes,Mariscos,Fresas,Tomates,Chocolate,Polen,Gatos]\r\n-- (0.01 secs, 598,152 bytes)\r\n-- \u03bb> last (map alergias5 [1..255])\r\n-- [Huevos,Cacahuetes,Mariscos,Fresas,Tomates,Chocolate,Polen,Gatos]\r\n-- (0.01 secs, 596,888 bytes)\r\n<\/pre>\nEl c\u00f3digo se encuentra en [GitHub](https:\/\/github.com\/jaalonso\/Exercitium\/blob\/main\/src\/Alergias.hs).<\/p>\n
La elaboraci\u00f3n de las soluciones se describe en el siguiente v\u00eddeo<\/p>\n
Nuevas soluciones<\/h4>\n\n- En los comentarios se pueden escribir nuevas soluciones.\n
- El c\u00f3digo se debe escribir entre una l\u00ednea con <pre lang="haskell"> y otra con <\/pre>\n<\/ul>\n
[\/schedule]<\/p>\n","protected":false},"excerpt":{"rendered":"
Para la determinaci\u00f3n de las alergia se utiliza los siguientes c\u00f3digos para los al\u00e9rgenos: Huevos …….. 1 Cacahuetes …. 2 Mariscos …… 4 Fresas …….. 8 Tomates ……. 16 Chocolate ….. 32 Polen ……… 64 Gatos ……… 128 As\u00ed, si Juan es al\u00e9rgico a los cacahuetes y al chocolate, su puntuaci\u00f3n es 34 (es decir,…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"footnotes":"","_jetpack_memberships_contains_paid_content":false},"categories":[2],"tags":[483,8,498,30,26,38,338,80,71,10,538,537,92,11,6,31,16,88,539,40,146,503,87,9],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/6894"}],"collection":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/comments?post=6894"}],"version-history":[{"count":1,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/6894\/revisions"}],"predecessor-version":[{"id":6895,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/6894\/revisions\/6895"}],"wp:attachment":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/media?parent=6894"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/categories?post=6894"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/tags?post=6894"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}