Recursion - dab tsi yog qhov no? Recursion programming (Piv txwv)

Recursion yog nthuav cov txheej xwm nyob rau hauv lawv tus kheej, tab sis lawv yog nyob rau hauv lub cajmeem kev tseem ceeb nyob rau hauv tej rooj plaub. Rau cov thawj lub sij hawm confronted nrog lawv, ib tug ncaj loj tus naj npawb ntawm cov neeg muaj nrog rau lawv cov kev nkag siab ntawm qhov teeb meem. Qhov no yog vim muaj ib tug loj loj teb ntawm tej kev siv ntawm lub sij hawm, nyob ntawm seb lub ntsiab lus teb nyob rau hauv uas lub "recursion" siv. Tab sis nws yog vam hais tias qhov no tsab xov xwm yuav pab tau kom tsis txhob tau misunderstandings thiab tsis meej pem.

Yuav ua li cas yog lub "recursion" nyob rau hauv kev?

Lo lus "recursion" muaj ib tug ntau ntawm qhov tseem ceeb uas yog nyob rau hauv lub cheeb tsam nyob rau hauv uas nws yog thov. Universal los yog raws li nram no: recursion - qhov no txhais dluab, piav txog ntawm cov khoom los yog dab nyob rau hauv cov khoom rau lawv tus kheej. lawv yeej ua tau xwb nyob rau hauv tus neeg mob qhov twg cov kwv yog ib feem ntawm nws tus kheej. Nyob rau hauv nws tus kheej txoj kev uas nws txhais recursive lej, physics, programming, thiab ib tug xov tooj ntawm lwm yam kev qhuab qhia. Lub tswv yim daim ntawv thov yog pom nyob rau hauv cov ntaub ntawv systems thiab lub cev thwmsim.

Yuav ua li cas yog meant by recursion nyob rau hauv programming?

Recursive lub sijhawm los yog recursion nyob rau hauv lub cajmeem, hu ua lub sij hawm thaum txoj kev sai los yog qhov kev pab cuam muaj nuj nqi hu nws tus kheej. Raws li coj txawv txawv rau cov neeg uas tau pib kawm programming, raws li qhov no tej zaum yuav suab, muaj yog tsis muaj dab tsi coj txawv txawv hais txog nws. Nco ntsoov hais tias cov recursion - nws tsis yog yooj yim, thiab nyob rau hauv tej rooj plaub lawv hloov mus. Yog hais tias koj lub computer teem kom hu rau ib tug txoj kev los yog muaj nuj nqi, nws cia li pib mus nqa nws.

Recursion yuav ua tau finite los yog infinite. Yuav kom thawj nres nws tus kheej ua, nws yuav tsum kuj yuav tej yam kev mob ntawm kev txiav. Qhov no txo nyob rau hauv tus nqi yuav ua tau nce mus nce los, thiab thaum nws nce mus txog ib tug tej yam muaj nuj nqis, thiab tsis txhob hu tiav software / kev hloov mus rau lub tom ntej code, nyob ntawm seb cov kev xav tau mus cuag tej hom phiaj. Los ntawm infinite recursion implies hais tias nws yuav tsum tau hu ua, yuav ua hauj lwm raws li ntev raws li ib tug computer los yog ib qho kev pab nyob rau hauv uas nws ua hauj lwm.

Nws yog tseem tau rau lub koom haum yooj yim recursion siv ob zog. Piv txwv muaj A thiab B. Ib tug muaj ib tug muaj nuj nqi nyob rau hauv koj cov cai hu rau B, thiab B, nyob rau hauv lem, cov ntsiab lus rau qhov yuav tsum tau rau ib lub computer mus ua tau ib tug complex A. recursion - ib txoj kev tawm ntawm ib tug complex series ntawm cov zajlus kom lub sijhawm rau computer logic.

Yog hais tias tus nyeem ntawv ntawm cov kab kawm programming mus, nws yog tej zaum twb pom qhov sib thooj ntawm lawv thiab recursion. Nyob rau hauv Feem ntau, lawv muaj peev xwm ua tau ua zoo sib xws los zoo tib yam kev pab raws qib. Nrog kev pab los ntawm recursion yog yooj yim ua simulation kev ua hauj lwm mus los. Qhov no yog tshwj xeeb yog pab tau qhov twg lub mus rau lawv tus kheej siv tsis yog yooj yim heev. Tsav software siv yog tsis sib txawv heev nyob rau hauv txawv high-theem programming lus. Tsis tau recursion nyob rau hauv lub "Pascal" thiab recursion nyob rau hauv C los yog lwm hom lus nws muaj nws tus yam ntxwv. Nws muaj peev xwm yuav ntse los siv nyob rau hauv low-level hom lus xws li "assembler", tab sis nws yog ntau problematic thiab lub sij hawm siv.

ntoo recursion

Yuav ua li cas yog ib tug "tsob ntoo" nyob rau hauv lub programming? Nws yog ib tug finite set muaj tsawg kawg yog ib ntawm uas yog:

1. Muaj ib tug thawj zaug tshwj xeeb ntawm, hu ua lub hauv paus ntawm lub tag nrho tsob ntoo.
2. Qhov seem ntshav yog nyob rau hauv ib tug npaum li uas yog txawv los ntawm xoom, disjoint subsets, nyob rau tib lub sij hawm lawv kuj muaj ib tug ntoo. Txhua yam ntaub ntawv ntawm lub koom haum hu ua cov subtrees ntawm lub ntsiab tsob ntoo.

Nyob rau hauv lwm yam lus: ntoo muaj subtrees uas muaj ntau cov ntoo, tab sis nyob rau hauv me me xov tooj tshaj yav dhau los tsob ntoo. Qhov no tseem mus txog rau thaum ib tug ntawm cov ntshav yuav tsum tau mus rau, thiab nws yuav txhais li cas rau hauv lub kawg ntawm tus recursion. Muaj yog ib tug ntau nuance txog diagramming: zoo tib yam ntoo loj hlob los ntawm lub hauv qab, thiab lawv yog twv rau programming vice versa. Qhov chaw uas muaj tsis muaj txuas ntxiv, hu ua kawg o. Rau kev kab ntsab ntawm cim, thiab rau yooj yim ntawm kev siv genealogical terminology (pog koob yawg koob, cov me nyuam).

Yog vim li cas nws yog siv nyob rau hauv lub cajmeem?

Nws siv cov recursion nyob rau hauv programming nyob rau ib tug ntau ntawm complex paub tab. Yog hais tias koj xav mus ua tsuas yog ib qho hu, qhov yooj yim dua yog cov kev siv ntawm cov koom ua ke voj voog, tab sis thaum ob tug los yog ntau tshaj repetitions kom tsis txhob chaining thiab ua kom lawv siv nyob rau hauv daim ntawv ntawm ib tsob ntoo, thiab recursive lub sijhawm thov. Rau ntau chav kawm ntawv ntawm cov teeb meem hauv lub koom haum ntawm koj laij cov txheej txheem nyob rau hauv no txoj kev yog qhov zoo tshaj plaws nyob rau hauv cov nqe lus ntawm kev pab noj. Yog li, lub recursion nyob rau hauv "Pascal" los yog lwm yam high-theem programming lus yog ib tug muaj nuj nqi los yog txoj kev hu mus rau lub tej yam kev mob tsis hais ntawm tus xov tooj ntawm lwm hu. Nyob rau hauv lwm yam lus, qhov kev pab cuam yuav ua tau tsuas yog ib tug hu mus rau lub subroutine, tab sis nws yuav ua tau mus txog rau ib tug tej predetermined torque. Nyob rau hauv ib co txoj kev uas nws yog ib qho analog voj nrog nws siv cov yam ntxwv.

Txawv recursion nyob rau hauv ntau yam programming lus

Dua li ntawm qhov general daim duab ntawm ib tug siv thiab cov kev daim ntawv thov nyob rau hauv txhua tus neeg cov ntaub ntawv, recursion nyob rau hauv programming nws muaj nws tus yam ntxwv. Qhov no yuav ua rau kev nyuaj nyob rau hauv cov kev tshawb fawb rau qhov yuav tsum tau cov ntaub ntawv uas. Tab sis yeej ib txwm nco ntsoov: yog hais tias hom lus programming yog ib tug muaj nuj nqi los yog txoj kev, yog li ntawd, tus hu recursion - nws yog ua tau. Tab sis nws feem ntau qhov sib txawv tshwm sim thaum uas siv cov tsawg tsawg thiab siab programming lus. Qhov no yog tshwj xeeb tshaj yog muaj tseeb possibilities ntawm qhov kev pab cuam siv. Tiav yuav kawg nyob ntawm seb seb tus neeg ua hauj lwm yog teeb, nyob rau hauv raws li nws thiab sau recursion. Tso cai thiab cov txheej txheem siv los yog sib txawv, tab sis lawv lub hom phiaj yog ib txwm zoo li qub - ua lub hu lawv tus kheej.

Recursion - nws yog ib qho yooj yim. Raws li ib qho yooj yim uas yuav tau nco rau hauv lub ntsiab lus ntawm tsab xov xwm?

Rau beginners to taub nws yuav ua tau yooj yim thaum xub thawj, yog li koj yuav tsum piv txwv ntawm recursion, los yog tsawg kawg yog ib tug. Yog li ntawd, koj yuav tsum tau muab ib tug me me piv txwv ntawm lub neej txhua hnub, uas yuav pab tau kom koj to taub cov essence ntawm no mechanism mus cuag lub hom phiaj nyob rau hauv lub programming. Siv ob los sis ntau tsom iav, muab rau lawv kom nyob rau hauv ib cov zaub tag nrho tus so. Nws yuav pom tias lub tsom iav muaj kev cuam tshuam rau nws tus kheej pheej hais dua, txoj kev kom cov nyhuv ntawm infinity. Ntawm no recursion - yog, figuratively hais lus, lub reflections (uas yog ib tug ntau). Raws li koj tau pom, ib qho yooj yim to taub, nws yuav xav. Ib txoj kev tshawb ntawm programming cov ntaub ntawv, ces peb yuav pom tias recursion - nws tseem yog yooj yim heev phaaj tseem ceeb hab ua hauj lwm.