{"id":7917,"date":"2023-02-27T06:00:54","date_gmt":"2023-02-27T04:00:54","guid":{"rendered":"http:\/\/www.glc.us.es\/~jalonso\/exercitium\/?p=7917"},"modified":"2023-01-27T19:59:51","modified_gmt":"2023-01-27T17:59:51","slug":"27-feb-23","status":"publish","type":"post","link":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/27-feb-23\/","title":{"rendered":"TAD de las colas: M\u00e1ximo elemento de una cola"},"content":{"rendered":"

Utilizando el tipo abstracto de datos de las colas<\/a>, definir la funci\u00f3n<\/p>\n

\n   maxCola :: Ord a => Cola a -> a\n<\/pre>\n
tal que maxCola c<\/code> sea el mayor de los elementos de la cola c<\/code>. Por ejemplo,<\/p>\n
\n   \u03bb> maxCola (inserta 3 (inserta 5 (inserta 1 vacia)))\n   5\n<\/pre>\n
Soluciones<\/b><\/p>\n
A continuaci\u00f3n se muestran las soluciones en Haskell<\/a> y las soluciones en Python<\/a>.<\/p>\n
<\/a>
\nSoluciones en Haskell<\/b><\/p>\n
\nimport TAD.Cola (Cola, vacia, inserta, esVacia, primero, resto)\nimport Transformaciones_colas_listas (colaAlista)\nimport Test.QuickCheck\n\n-- 1\u00aa soluci\u00f3n\n-- ===========\n\nmaxCola1 :: Ord a => Cola a -> a\nmaxCola1 c\n  | esVacia rc = pc\n  | otherwise  = max pc (maxCola1 rc)\n  where pc = primero c\n        rc = resto c\n\n-- 2\u00aa soluci\u00f3n\n-- ===========\n\nmaxCola2 :: Ord a => Cola a -> a\nmaxCola2 =\n  maximum . colaAlista\n\n-- La funci\u00f3n colaAlista est\u00e1 definida en el ejercicio\n-- \"Transformaciones entre colas y listas\" que se encuentra en\n-- https:\/\/bit.ly\/3Xv0oIt\n\n-- Comprobaci\u00f3n de equivalencia\n-- ============================\n\n-- La propiedad es\nprop_maxCola :: Cola Int -> Property\nprop_maxCola c =\n  not (esVacia c) ==> maxCola1 c == maxCola2 c\n\n-- La comprobaci\u00f3n es\n--    \u03bb> quickCheck prop_maxCola\n--    +++ OK, passed 100 tests; 16 discarded.\n<\/pre>\n
<\/a>
\nSoluciones en Python<\/b><\/p>\n
\nfrom copy import deepcopy\nfrom typing import TypeVar\n\nfrom hypothesis import assume, given\n\nfrom src.TAD.cola import (Cola, colaAleatoria, esVacia, inserta, primero,\n                          resto, vacia)\nfrom src.transformaciones_colas_listas import colaAlista\n\nA = TypeVar('A', int, float, str)\n\n# 1\u00aa soluci\u00f3n\n# ===========\n\ndef maxCola1(c: Cola[A]) -> A:\n    pc = primero(c)\n    rc = resto(c)\n    if esVacia(rc):\n        return pc\n    return max(pc, maxCola1(rc))\n\n# 2\u00aa soluci\u00f3n\n# ===========\n\n# Se usar\u00e1 la funci\u00f3n colaAlista del ejercicio\n# \"Transformaciones entre colas y listas\" que se encuentra en\n# https:\/\/bit.ly\/3ZHewQ8\n\ndef maxCola2(c: Cola[A]) -> A:\n    return max(colaAlista(c))\n\n# 3\u00aa soluci\u00f3n\n# ===========\n\ndef maxCola3Aux(c: Cola[A]) -> A:\n    pc = c.primero()\n    c.resto()\n    if esVacia(c):\n        return pc\n    return max(pc, maxCola3Aux(c))\n\ndef maxCola3(c: Cola[A]) -> A:\n    _c = deepcopy(c)\n    return maxCola3Aux(_c)\n\n# 4\u00aa soluci\u00f3n\n# ===========\n\ndef maxCola4Aux(c: Cola[A]) -> A:\n    r = c.primero()\n    while not esVacia(c):\n        pc = c.primero()\n        if pc > r:\n            r = pc\n        c.resto()\n    return r\n\ndef maxCola4(c: Cola[A]) -> A:\n    _c = deepcopy(c)\n    return maxCola4Aux(_c)\n\n# Comprobaci\u00f3n de equivalencia de las definiciones\n# ================================================\n\n# La propiedad es\n@given(c=colaAleatoria())\ndef test_maxCola(c: Cola[int]) -> None:\n    assume(not esVacia(c))\n    r = maxCola1(c)\n    assert maxCola2(c) == r\n    assert maxCola3(c) == r\n    assert maxCola4(c) == r\n\n# La comprobaci\u00f3n es\n#    src> poetry run pytest -q maxCola.py\n#    1 passed in 0.30s\n<\/pre>\n","protected":false},"excerpt":{"rendered":"
Utilizando el tipo abstracto de datos de las colas, definir la funci\u00f3n maxCola :: Ord a => Cola a -> a tal que maxCola c sea el mayor de los elementos de la cola c. Por ejemplo, \u03bb> maxCola (inserta 3 (inserta 5 (inserta 1 vacia))) 5 Soluciones A continuaci\u00f3n se muestran las soluciones en…<\/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":[581],"tags":[515,585],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/7917"}],"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=7917"}],"version-history":[{"count":1,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/7917\/revisions"}],"predecessor-version":[{"id":7918,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/7917\/revisions\/7918"}],"wp:attachment":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/media?parent=7917"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/categories?post=7917"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/tags?post=7917"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}