{"id":7898,"date":"2023-02-16T06:00:45","date_gmt":"2023-02-16T04:00:45","guid":{"rendered":"http:\/\/www.glc.us.es\/~jalonso\/exercitium\/?p=7898"},"modified":"2023-01-26T13:17:20","modified_gmt":"2023-01-26T11:17:20","slug":"16-feb-23","status":"publish","type":"post","link":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/16-feb-23\/","title":{"rendered":"TAD de las colas: Intercalado de dos colas"},"content":{"rendered":"<p>Utilizando el <a href=\"https:\/\/bit.ly\/3QWTsRL\">tipo abstracto de datos de las colas<\/a>, definir la funci\u00f3n<\/p>\n<pre lang=\"text\">\n   intercalaColas :: Cola a -> Cola a -> Cola a\n<\/pre>\n<p>tal que <code>intercalaColas c1 c2<\/code> es la cola formada por los elementos de <code>c1<\/code> y <code>c2<\/code> colocados en una cola, de forma alternativa, empezando por los elementos de c1. Por ejemplo,<\/p>\n<pre lang=\"text\">\n   \u03bb> ej1 = inserta 3 (inserta 5 vacia)\n   \u03bb> ej2 = inserta 0 (inserta 7 (inserta 4 (inserta 9 vacia)))\n   \u03bb> intercalaColas ej1 ej2\n   5 | 9 | 3 | 4 | 7 | 0\n   \u03bb> intercalaColas ej2 ej1\n   9 | 5 | 4 | 3 | 7 | 0\n<\/pre>\n<p><b>Soluciones<\/b><\/p>\n<p>A continuaci\u00f3n se muestran las <a href=\"#haskell\">soluciones en Haskell<\/a> y las <a href=\"#python\">soluciones en Python<\/a>.<\/p>\n<p><a name=\"haskell\"><\/a><br \/>\n<b>Soluciones en Haskell<\/b><\/p>\n<pre lang=\"haskell\">\nimport TAD.Cola (Cola, vacia, inserta, primero, resto, esVacia)\nimport Transformaciones_colas_listas (colaAlista, listaAcola)\nimport ExtiendeCola (extiendeCola)\nimport Test.QuickCheck\n\n-- 1\u00aa soluci\u00f3n\n-- ===========\n\nintercalaColas :: Cola a -> Cola a -> Cola a\nintercalaColas c1 c2\n  | esVacia c1 = c2\n  | esVacia c2 = c1\n  | otherwise  = extiendeCola (inserta pc2 (inserta pc1 vacia))\n                              (intercalaColas rc1 rc2)\n  where pc1 = primero c1\n        rc1 = resto c1\n        pc2 = primero c2\n        rc2 = resto c2\n\n-- La funci\u00f3n extiendeCola est\u00e1 definida en el ejercicio\n-- \"TAD de las colas: Extensi\u00f3n de colas\" que se encuentra en\n-- https:\/\/bit.ly\/3XIJJ4m\n\n-- 2\u00aa soluci\u00f3n\n-- ===========\n\nintercalaColas2 :: Cola a -> Cola a -> Cola a\nintercalaColas2 c1 c2 = aux c1 c2 vacia\n  where\n    aux d1 d2 c\n      | esVacia d1 = extiendeCola c d2\n      | esVacia d2 = extiendeCola c d1\n      | otherwise  = aux rd1 rd2 (inserta pd2 (inserta pd1 c))\n      where pd1 = primero d1\n            rd1 = resto d1\n            pd2 = primero d2\n            rd2 = resto d2\n\n-- 3\u00aa soluci\u00f3n\n-- ===========\n\nintercalaColas3 :: Cola a -> Cola a -> Cola a\nintercalaColas3 c1 c2 =\n  listaAcola (intercalaListas (colaAlista c1) (colaAlista c2))\n\n-- (intercalaListas xs ys) es la lista obtenida intercalando los\n-- elementos de xs e ys. Por ejemplo,\nintercalaListas :: [a] -> [a] -> [a]\nintercalaListas []     ys     = ys\nintercalaListas xs     []     = xs\nintercalaListas (x:xs) (y:ys) = x : y : intercalaListas xs ys\n\n-- Comprobaci\u00f3n de equivalencia\n-- ============================\n\n-- La propiedad es\nprop_intercalaColas :: Cola Int -> Cola Int -> Bool\nprop_intercalaColas c1 c2 =\n  all (== intercalaColas c1 c2)\n      [intercalaColas2 c1 c2,\n       intercalaColas2 c1 c2]\n\n-- La comprobaci\u00f3n es\n--    \u03bb> quickCheck prop_intercalaColas\n--    +++ OK, passed 100 tests.\n<\/pre>\n<p><a name=\"python\"><\/a><br \/>\n<b>Soluciones en Python<\/b><\/p>\n<pre lang=\"python\">\nfrom copy import deepcopy\nfrom typing import TypeVar\n\nfrom hypothesis import given\n\nfrom src.extiendeCola import extiendeCola\nfrom src.TAD.cola import (Cola, colaAleatoria, esVacia, inserta, primero,\n                          resto, vacia)\nfrom src.transformaciones_colas_listas import colaAlista, listaAcola\n\nA = TypeVar('A')\n\n# 1\u00aa soluci\u00f3n\n# ===========\n\ndef intercalaColas(c1: Cola[A], c2: Cola[A]) -> Cola[A]:\n    if esVacia(c1):\n        return c2\n    if esVacia(c2):\n        return c1\n    pc1 = primero(c1)\n    rc1 = resto(c1)\n    pc2 = primero(c2)\n    rc2 = resto(c2)\n    return extiendeCola(inserta(pc2, inserta(pc1, vacia())),\n                        intercalaColas(rc1, rc2))\n\n# La funci\u00f3n extiendeCola est\u00e1 definida en el ejercicio\n# \"TAD de las colas: Extensi\u00f3n de colas\" que se encuentra en\n# https:\/\/bit.ly\/3XIJJ4m\n\n# 2\u00aa soluci\u00f3n\n# ===========\n\ndef intercalaColas2(c1: Cola[A], c2: Cola[A]) -> Cola[A]:\n    def aux(d1: Cola[A], d2: Cola[A], d3: Cola[A]) -> Cola[A]:\n        if esVacia(d1):\n            return extiendeCola(d3, d2)\n        if esVacia(d2):\n            return extiendeCola(d3, d1)\n        pd1 = primero(d1)\n        rd1 = resto(d1)\n        pd2 = primero(d2)\n        rd2 = resto(d2)\n        return aux(rd1, rd2, inserta(pd2, inserta(pd1, d3)))\n\n    return aux(c1, c2, vacia())\n\n# 3\u00aa soluci\u00f3n\n# ===========\n\n# intercalaListas(xs, ys) es la lista obtenida intercalando los\n# elementos de xs e ys. Por ejemplo,\ndef intercalaListas(xs: list[A], ys: list[A]) -> list[A]:\n    if not xs:\n        return ys\n    if not ys:\n        return xs\n    return [xs[0], ys[0]] + intercalaListas(xs[1:], ys[1:])\n\ndef intercalaColas3(c1: Cola[A], c2: Cola[A]) -> Cola[A]:\n    return listaAcola(intercalaListas(colaAlista(c1), colaAlista(c2)))\n\n# 4\u00aa soluci\u00f3n\n# ===========\n\ndef intercalaColas4Aux(c1: Cola[A], c2: Cola[A]) -> Cola[A]:\n    if c1.esVacia():\n        return c2\n    if c2.esVacia():\n        return c1\n    pc1 = c1.primero()\n    c1.resto()\n    pc2 = c2.primero()\n    c2.resto()\n    return extiendeCola(inserta(pc2, inserta(pc1, vacia())),\n                        intercalaColas4Aux(c1, c2))\n\ndef intercalaColas4(c1: Cola[A], c2: Cola[A]) -> Cola[A]:\n    _c1 = deepcopy(c1)\n    _c2 = deepcopy(c2)\n    return intercalaColas4Aux(_c1, _c2)\n\n# 5\u00aa soluci\u00f3n\n# ===========\n\ndef intercalaColas5Aux(c1: Cola[A], c2: Cola[A]) -> Cola[A]:\n    r: Cola[A] = vacia()\n    while not esVacia(c1) and not esVacia(c2):\n        pc1 = primero(c1)\n        c1.resto()\n        pc2 = primero(c2)\n        c2.resto()\n        r = inserta(pc2, inserta(pc1, r))\n    if esVacia(c1):\n        return extiendeCola(r, c2)\n    return extiendeCola(r, c1)\n\ndef intercalaColas5(c1: Cola[A], c2: Cola[A]) -> Cola[A]:\n    _c1 = deepcopy(c1)\n    _c2 = deepcopy(c2)\n    return intercalaColas5Aux(_c1, _c2)\n\n# Comprobaci\u00f3n de equivalencia\n# ============================\n\n# La propiedad es\n@given(c1=colaAleatoria(), c2=colaAleatoria())\ndef test_extiendeCola(c1: Cola[int], c2: Cola[int]) -> None:\n    r = intercalaColas(c1, c2)\n    assert intercalaColas2(c1, c2) == r\n    assert intercalaColas3(c1, c2) == r\n    assert intercalaColas4(c1, c2) == r\n    assert intercalaColas5(c1, c2) == r\n\n# La comprobaci\u00f3n es\n#    src> poetry run pytest -q intercalaColas.py\n#    1 passed in 0.47s\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Utilizando el tipo abstracto de datos de las colas, definir la funci\u00f3n intercalaColas :: Cola a -> Cola a -> Cola a tal que intercalaColas c1 c2 es la cola formada por los elementos de c1 y c2 colocados en una cola, de forma alternativa, empezando por los elementos de c1. Por ejemplo, \u03bb> ej1&#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":[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\/7898"}],"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=7898"}],"version-history":[{"count":1,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/7898\/revisions"}],"predecessor-version":[{"id":7899,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/posts\/7898\/revisions\/7899"}],"wp:attachment":[{"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/media?parent=7898"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/categories?post=7898"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.glc.us.es\/~jalonso\/exercitium\/wp-json\/wp\/v2\/tags?post=7898"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}