Turbo Pascal. Nangona ... do - loop nge njengomqathango

Turbo NjengoPascal, nangona akukho isicelo owuthandayo senkqubo ehlabathini, kodwa kwabayili, benza amanyathelo yabo yokuqala lokubhalwa software, qala ukuqhelana lwabo ngale ndlela. Oku kunika uluvo lokuba nokunaba, abasebenzisi, imisebenzi, kunye neenkqubo, kwakunye nezinye izinto ezininzi. Ngokomzekelo, kwisifundo umdwelisi nkqubo ubuso yemijikelo Turbo UPascal: Nangona, kuba no Phinda.

Ingcamango komjikelo ezahlukeneyo

A umjikelezo isenzo phinda. Kule meko, sebenzisa:

• nge parameter (Kuba ... ukuba ... do);
• kunye yangaphambili (Ngoxa ... do);
• a postcondition (Phinda ... de).

Uhlobo lokuqala lisetyenziselwa naxa kusaziwa amanyathelo amaninzi kangakanani ekusombululeni ingxaki. Nakuba kunjalo, kukho iqela lemisebenzi, apho kungekho ulwazi malunga nendlela zizihlandlo ezingaphi ziza kuphindwa okanye amanyathelo. Kulo mzekelo, Pascal Ngoxa umjikelo uba buyafuneka, ezifana, isimiso, kwaye Phinda.

Ubume komjikelo

Yintoni ngumongo umsebenzi Pascal gama, kuba kwaye Phinda imijikelo? Xa lwakhiwo lunokuthi anikezele header kunye nomzimba. Ilungu yokuqala yezahlukileyo ezichaziweyo eziya "umsebenzi" icaciswe iimeko kwi kwixesha apho umzimba uya kubulawa. Kwinxalenye yesibini amabinzana emiselweyo ukuba isetyenziswe kwimeko imeko, okt. E. Lokwenene, endaweni False.

Xa uniko lwenziwa kumgca wokugqibela ikhowudi, ngoko ubuyela header, apho imeko ivavanywa. Ukuba imisebenzi inyaniso ngxelo zilolu hlobo ziphinda, kwaye xa kunokwenzeka naluphi na ulwaphulo lwenkqubo 'Exit "kumjikelo kwaye yenza eminye imisebenzi.

Ulandela ngokuqwayinga Nakuba loop. Pascal ABC kunye neenkqubo ezifana lifune ukubhala ikhowudi ezifana:

• Nangona imeko ukwenza;
• Qala;
• Umzimba loop;
• End.

Kwimeko yokuba ndzhendzheleko kuya kwenziwa 1 umqhubi (1 action), ngoko ke "kwizibiyeli» siqale ... ukuphela zisalelayo.

umjikelezo Umzobo wokulandelana kweenkqubo

I Turbo Pascal Nangona ezi mpawu zilandelayo:

• ngaphakathi isakhiwo kunokuba nzima ukusebenzisa iimeko;
• emva kwegama ukwenza akufunekanga ibe isiphumlisi (kucingwa yegciwane Turbo UPascal kunye Pascal ABC);
• variable, rhoqo okanye ibinzana lisebenza xa impendulo imveliso Asiyonyani kubo subroutines kufuneka nakanjani babe uhlobo enengqiqo, okt. e. Boolean.

Oko ngolu hlobo lulandelayo block umzobo womjikelo ezahlukeneyo. Ibonisa ulandelelwano yezenzo zokuphunyezwa.

I algorithm komjikelo

.. Xa iimeko kweenkqubo kwecacileyo, m kunye h e Pascal ABC, Ngoxa loop isebenza-siseko ilandelayo:

• .. uniko Uphile, oko kukuthi, uphindaphindo, luya kuqhubeka njengoko amaxesha amaninzi logama nje imeko liyinyaniso (True);
• ngokukhawuleza kangangoko imeko akanelisekanga aze anike impendulo Asiyonyani (okanye ngenye "Wamanga"), iBhodi ngaphandle yomtya;
• ngokukhawuleza Kwathi, inkqubo 'wahamba' kuyilo ukubonakala emva umjikelo.

Oku umahluko omkhulu evela Nangona Phinda, t. E. A-Umjikelo yaphambi ukusuka postconditions.

Kubalulekile ukubandakanya kwi loop utshintsho ezisikelwe kungabekwa header Nakuba bume. Xa kunjalo, kufuneka ufike imeko enika False. Kungenjalo akuyi kubakho ndzhendzheleko, uze emva koko kufuneka athathe amanyathelo eyongezelelweyo ziphume emafini. iimpazamo ezilolu hlobo ingqalelo ekrwada nakungxengxezeleka.

Indlela ukuphuma inkqubo ngelixa ngeebhayisikile?

Kaninzi kwenzeka xa umqhubi unika Nangona Pascal yomtya ikhowudi program ebhaliweyo. Kuthetha ntoni oku? Uniko lomyalelo iphindwa inani olungenasiphelo izihlandlo, kuba imeko njalo. Umzekelo, oku ukuqhekeka ikhowudi:

• Nangona 2> 1 kuyenza;
• Bhala (1).

Kulo mzekelo, ukuba ukuphazamisa ekwenziweni komsebenzi, vele ucinizele Ctrl + F2.

Kukho 2 iindlela zokulawula ukuziphatha inkqubo enjalo. Umzekelo, ukuba ubhale Qhubeka ikhowudi ludlulele ulawulo ukuya ekuqaleni ngesakhiwo elibujikele (apha imeko uphumo ngokwenzekayo iliso, okt. E ukubulawa le uniko yangoku uphazamiseka). Emva koko ulawulo ufuduswa ndzhendzheleko Ngoxa kuvavanyo lwangaphambili.

umqhubi Break nga ukuphazamisa ukubulawa komjikelo uphela nokudlulisela ulawulo ukuya uniko lomyalelo olandelayo. Apha, imveliso lolwakhiwo akayi ilawulwe. Lo mfanekiso ubonisa imizekelo ukusetyenziswa kwezi basebenzi.

Ukwanelisa mngeni

Cinga Xa kumjikelo operation. Pascal iceba ukusombulula ingxaki lwaya. Makhe sihlolisise indlela elula ukuqonda ukusebenza. imisebenzi isonjululwe kwinkqubo Pascal ABC. Kodwa kuya thaca kunye nomfanekiso ka Turbo UPascal bume ezivunywa uthelekiso.

Umsebenzi 1: banikwa umsebenzi Y = 5-X ^ 2/2. Yenza itafile lamaxabiso yokunyuka sh = 0,5 phezu lokuphumla [-5, 5].

I algorithm:

• umise X kwi inani lokuqala ilingana no-5 (ithetha ukuba isiqalo isikhewu ..);
• ukubala inani Y, lo gama i-x-bume alifikeleli isiphelo lokuphumla wathi;
• ukubonisa amaxabiso umsebenzi kunye abscissa (X);
• X ngokonyuswa linyathelo kwangaphambili.

Nantsi ikhowudi kwinkqubo Pascal ABC.

wenza njani ikhowudi kwinkqubo Turbo Pascal. Le mifanekiso ingezantsi ibonisa oku.

Umsebenzi 2: wanikwa uluhlu A eyenziwa lonke amanani akhabayo kunye navumelanayo. Iqulethe izinto-10. Imfuneko ukwenza isizalo apho izinto ezintle uluhlu A ziboniswa ukuba ube index. Bonisa udibaniso lwezikweri inani matrix entsha.

I algorithm:

• Kufuneka ubhale izinto oya "umsebenzi" kuphela iziqalelo uluhlu A ukuba ube index. Kwi loop ixabiso elitshintshayo ehambelana ukubekwa isalathisi incremented yi ezimbini.
• Ukuba inani lude isalathisi ukususka kwi isizalo A elivumelana imeko x> 0, uluhlu counter leyo incremented yi 1. Ixabiso sangoku counter bume iya kuba kwisalathiso inombolo ikopi kwi uluhlu B.
• Ekuqaleni, lo nesimva bume, unoxanduva ekufumaneni udibaniso lwezikweri integers ezintle, umiselwe no 0. Ngoko, lo msebenzi uya kwenziwa, isamba oludlulileyo wongeza ixabiso elitsha lwe ngcambu.
• Musa ukuba uyoyika, ukuba asingabo bonke amanani akhabayo yasuswa ukusuka kwelinye uluhlu ukuya kwenye. Kufuneka silumke. badwelisi benkqubo abaninzi makhwelo ukuba ubhale ikhowudi kwi yokothuka. Kuyimfuneko ukuba bahlolisise ngenyameko imeko: amanani akhabayo ezinamaxabiso nkqu "ekuhlaleni", oko kukuthi, kunye indices ukuba phindo luka-2 ...

ukope Manual kuyimfuneko ukuze kuqinisekiswe ukuba ukubala ukunyaniseka. Maxa wambi, usebenzisa le ndlela uyakwazi ukubona iimpazamo musa ukubamba iliso ehlolwa okuqhelekileyo ikhowudi ebhaliweyo.

Ukuba siphatha izibalo manual, kunokwenzeka ukuqinisekisa ukuba inkqubo isebenza kakuhle. Oku, wathi algorithm isizukulwana khowudi ilungile, ukulandelelana izenzo kukhokelela ekupheleni nengqondo.