{"id":4317,"date":"2018-11-22T06:00:56","date_gmt":"2018-11-22T04:00:56","guid":{"rendered":"http:\/\/www.glc.us.es\/~jalonso\/exercitium\/?p=4317"},"modified":"2019-01-19T12:21:22","modified_gmt":"2019-01-19T10:21:22","slug":"relacion-definida-por-una-particion","status":"publish","type":"post","link":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/relacion-definida-por-una-particion\/","title":{"rendered":"Relaci\u00f3n definida por una partici\u00f3n"},"content":{"rendered":"<p>Dos elementos est\u00e1n <a href=\"http:\/\/bit.ly\/2Q1FzVD\">relacionados por una partici\u00f3n<\/a> xss si pertenecen al mismo elemento de xss.<\/p>\n<p>Definir la funci\u00f3n<\/p>\n<pre lang=\"text\">\n   relacionados :: Eq a => [[a]] -> a -> a -> Bool\n<\/pre>\n<p>tal que (relacionados xss y z) se verifica si los elementos y y z est\u00e1n relacionados por la partici\u00f3n xss. Por ejemplo,<\/p>\n<pre lang=\"text\">\n   relacionados [[1,3],[2],[9,5,7]] 7 9  ==  True\n   relacionados [[1,3],[2],[9,5,7]] 3 9  ==  False\n   relacionados [[1,3],[2],[9,5,7]] 4 9  ==  False\n<\/pre>\n<h4>Soluciones<\/h4>\n<pre lang=\"haskell\">\nimport Data.List ((\\\\), intersect)\n\n-- 1\u00aa definici\u00f3n\n-- =============\n\nrelacionados :: Eq a => [[a]] -> a -> a -> Bool\nrelacionados [] _ _ = False\nrelacionados (xs:xss) y z\n  | y `elem` xs = z `elem` xs\n  | otherwise   = relacionados xss y z\n\n-- 2\u00aa definici\u00f3n\n-- =============\n\nrelacionados2 :: Eq a => [[a]] -> a -> a -> Bool\nrelacionados2 xss y z =\n  or [elem y xs && elem z xs | xs <- xss]\n\n-- 3\u00aa definici\u00f3n\n-- =============\n\nrelacionados3 :: Eq a => [[a]] -> a -> a -> Bool\nrelacionados3 xss y z =\n  or [[y,z] `subconjunto` xs | xs <- xss]\n\n-- (subconjunto xs ys) se verifica si xs es un subconjunto de ys; es\n-- decir, si todos los elementos de xs pertenecen a ys. Por ejemplo,  \n--    subconjunto [3,2,3] [2,5,3,5]  ==  True\n--    subconjunto [3,2,3] [2,5,6,5]  ==  False\nsubconjunto :: Eq a => [a] -> [a] -> Bool\nsubconjunto xs ys = and [elem x ys | x <- xs]\n\n-- 4\u00aa definici\u00f3n\n-- =============\n\nrelacionados4 :: Eq a => [[a]] -> a -> a -> Bool\nrelacionados4 xss y z =\n  any ([y,z] `subconjunto`) xss\n<\/pre>\n<h4>Pensamiento<\/h4>\n<blockquote><p>\nNo hay l\u00edo pol\u00edtico que no sea un trueque, una confusi\u00f3n de m\u00e1scaras, un mal ensayo de comedia, en que nadie sabe su papel.<\/p>\n<p>Antonio Machado\n<\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>Dos elementos est\u00e1n relacionados por una partici\u00f3n xss si pertenecen al mismo elemento de xss. Definir la funci\u00f3n relacionados :: Eq a => [[a]] -> a -> a -> Bool tal que (relacionados xss y z) se verifica si los elementos y y z est\u00e1n relacionados por la partici\u00f3n xss. Por ejemplo, relacionados [[1,3],[2],[9,5,7]] 7&#8230;<\/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":[5],"tags":[100,163,8,26,169,11,6],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/4317"}],"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=4317"}],"version-history":[{"count":4,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/4317\/revisions"}],"predecessor-version":[{"id":4595,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/4317\/revisions\/4595"}],"wp:attachment":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/media?parent=4317"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/categories?post=4317"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/tags?post=4317"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}