Yuav ua li cas yog cov ntaub ntawv hom nyob rau hauv Pascal?

Thaum lub cajmeem nyob rau hauv Pascal (Pascal) yuav tsum tau xaiv cov hom ntawm cov ntaub ntawv Pascal kev pab cuam. Lub programmer yog ib qho tseem ceeb kom to taub tias nyob rau hauv thiaj li yuav khiav nws qhov kev pab cuam qhov chaw khaws cov tsis tsuas cov teams faib nyob rau hauv lub cim xeeb, tab sis lub cov ntaub ntawv uas cov commands ua hauj lwm.

Tag nrho cov ntaub ntawv hom nyob rau hauv Pascal raug muab faib ua ob pawg: yooj yim thiab xyaum. Rau txhua hom ntawm cov ntaub ntawv yog muab ib tug tej yam muaj pes tsawg tus ntawm bytes. Rau tej yam yooj yim hom yog: integer hom (byte, integer, etc.), Khoom hom (tiag tiag, tib, thiab lwm yam), Boolean (boolean), cim hom (char), enumerated thiab luv hom. Tag nrho cov ntawm lawv, tshwj tsis yog lub tiag tiag hom yog ordinal hom thiab yog yus muaj nyob rau hauv hais tias lawv muaj ib tug limited txheej kom muaj nuj nqis. Piv txwv li, ib tug nce mus nce los muaj ib hom byte, yuav siv sij hawm qhov tseem ceeb xws li los ntawm 0 mus 255 inclusive. Tej ntaub ntawv hom nyob rau hauv Pascal cia mus thov cov nuj nqi Pred (laij ib tug yav dhau los tus nqi) thiab Succ (computes tom ntej tus nqi), Tsis tshua muaj (vychislyaetet tsawg tshaj plaws nqi hom) thiab High (laij cov coob tus nqi hom), Lo (nyob laij tam sim no tus nqi ntawm lub nce mus nce los tooj).

Tej raws li ib tug yooj yim hom qhov tseem ceeb muaj tsuas yog ib datum, i.e. ib tug integer, ib tug fractional tooj los yog ib lub cim. Zog muaj tej yam yooj yim cov ntaub ntawv hom, Pascal yuav tsum tau piav nyob rau hauv cov nqe lus Var (luv luv ntawm ntau yam -. Zog).

Cov nce mus nce los nyob rau hauv qhov kev pab cuam nyob rau hauv Pascal xam tau tias yog yuav tsum tau tag nrho teev, yog hais tias nws muaj ib lub npe (ID), cov hom thiab pib nqis. Lub npe ntawm lub nce mus nce los siv rau xa mus rau nws los ntawm tej yam neeg teb xov tooj. Cov ntaub ntawv hom qhia ib tug ntau yam sawv cev (uas tej zaum yuav siv sij hawm nce mus nce los qhov tseem ceeb), cov neeg ua haujlwm nyob rau hauv uas nws yuav tsum muab kev koom tes, cov nyiaj ntawm lub cim xeeb yuav tsum tau khaws tej tus kuj sib txawv nyob rau hauv lub cim xeeb. Yog li ntawd, kom daws tau qhov teeb meem yuav tsum yuav txo tus naj npawb ntawm ntau yam thiab muaj kuab xaiv ntawm ntau hom.

Structured hom yog ib tug txiav txim kom tso ntawm ntau yam ntawm tej yam yooj yim ntau hom. Cov muaj xws li: array (array), poob lawm (set ntawm), txoj hlua (hlua), cov ntaub ntawv (ntaub ntawv), cov ntaub ntawv (cov ntaub ntawv). Structured cov ntaub ntawv hom nyob rau hauv Pascal yog piav nyob rau hauv cov nqe lus hom (seem yam hauj lwm).

Array - lub feem ntau hom structured, yog siv tau thaum koj xav mus khaws thiab cov txheej txheem rau kom set ntawm ntau yam ntawm tib hom (tej yam yooj yim hom). Arrays yog ib tug-dimensional, two-dimensional, multi-dimensional. Ib qho piv txwv ntawm ib tug ib-seem array yuav pab raws li ib daim ntawv teev me nyuam kawm ntawv nyob rau hauv lub chav kawm ntawv magazine, txheeb nyob rau hauv alphabetical kev txiav txim, qhov chaw uas txhua tus menyuam kawm ntawv muaj ib tug tshwj xeeb serial tooj. Ib qho piv txwv ntawm ib tug ob-dimensional array - qhov chaw ntawm lub rooj zaum nyob rau hauv cov xinesmas nrog (txhua lub rooj yog txiav txim los ntawm ob ntsuam - lub kab thiab lub rooj tooj tooj).

Lub ntsiab ntawm tsis zoo li disordered array, thiab tus naj npawb ntawm cov ntsiab yog tas rau 255. Cov hlua muaj ib tug txiav txim kom tso cov cim thiab nws yog zoo heev rau cov array, txawm li cas los, tsuas yog lub cim yuav ua tau cov ntsiab ntawm txoj kab.

Cov ntaub ntawv - qhov no yog tib array, tab sis lub xov tooj ntawm cov ntsiab nyob rau hauv nws yuav tau hloov lub chav kawm ntawm qhov kev pab cuam. Rau cov ntaubntawv povthawj yog ib tug txheej ntawm ntau hom ntawm cov ntaub ntawv.

Los ntawm kev kawm siv cov ntaub ntawv hom nyob rau hauv Pascal, tau muab los siv heev thiab nthuav kev pab raws qib.