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[Powered by Google Translate] [MUSIC ROCK]

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[MUSIC - "HAPPY FLIMKIEN" il-fkieren]

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DAVID Malan: Illum, aħna jibdew esplorazzjoni tagħna ta 'l-

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fundamentali ta 'xjenza tal-kompjuter u l-introduzzjoni tagħna,

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issa, l-arti tal-ipprogrammar, li dan huwa

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biss eżempju wieħed.

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Iżda fl-istess ta 'soluzzjoni ta' problemi, nafu li

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Jum CS50 s Puzzle tradizzjonali hija għada.

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Jekk inti ħadthom għadha RSVPed għal dan l-avveniment, inti tista 'tmur

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cs50.net/rsvp.

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Inti tista 'ġġib timijiet ta' tnejn jew tlieta jew erba '.

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Inti ser tkun sfidata bi problemi bħall-waħda inti raw

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up hemm fil-bidu.

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Il-problemi kollha ġodda din is-sena jekk inti partook aħħar sena, u inti

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se jkollhom ċans allura li tirbaħ xi premjijiet fabulous.

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Fost dawn, Wii u xi ċertifikati rigal u simili,

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kollha filwaqt mdendlin mal CS50 istudenti u l-klassi

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u pizza u Facebook.

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Allura aktar fuq li għada jekk inti tixtieq.

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>> Dan allura huwa CS50, għal dawk tal inti jingħaqdu magħna għall-

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ewwel darba.

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U nafu li dan il-kors huwa partikolarment determinata li tikseb

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inti permezz dan il-kors lill-aħħar finali tiegħu, f'liema punt int

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se jkollu mhux biss għarfien ta 'dawn

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fundamentali tax-xjenza tal-kompjuter, iżda inti se jkollhom

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dan is-sett ħiliet prattiċi ħafna li inti tista 'mbagħad tieħu lura

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dipartiment tiegħek, jekk huwa xjenzi inġinerija,

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applikati matematika, x-xjenzi fiżiċi, naturali

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xjenza, jew simili.

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Tabilħaqq, dak hekk eċċitanti dwar ix-xjenza tal-kompjuter dawn

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jiem hija li huwa biss hekk applikabbli għall

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kull xorta ta 'oqsma.

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U anki jekk illum, aħna ser biss tobrox il-wiċċ ta '

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tradizzjonali ħafna programmar bil-lingwa magħrufa bħala C, aħna ser

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minflok tħares lejn xi ħaġa imsejħa Scratch, xi ħaġa ma

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li din l-istorja imħabba cookie ġiet implimentata minn wieħed mill tiegħek

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predeċessuri fis-snin li għaddew, li tgħid l-istejjer, biex joħolqu logħob,

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biex joħolqu arti interattiv, u li attwalment jibdew biex nagħlaq tagħna

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imħuħ madwar xi wħud mill-constructs fundamentali li

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sottostanti programmazzjoni iżda f'kuntest, kif tkun taf tara, li l-

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ħafna inqas scary, li ħafna inqas arcane, minn se tara

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qabel fit-tul.

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U realizzata, wisq, għal dawk tal inti biss jingħaqdu magħna din

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semestru, l-frażijiet li fuqhom għandna ntemmet lecture l-Erbgħa,

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mhuwiex daqshekk importanti fejn inti tispiċċa relattiva għall tiegħek

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klassi f'din il-klassi, imma fejn int, sa l-aħħar semestru tal-

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fil-ġimgħa 11, jispiċċaw relattiva għall lilek innifsek dritt illum stess.

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>> Allura mingħajr aktar dewmien, dan huwa wkoll min jinnota li

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dawk inqas komdi, dawk x'imkien bejniethom, huma

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ukoll, permezz tad-disinn ta 'dan il-kors, ma f'xi żvantaġġ

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vis-a-vis dawk aktar komdi

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bidu fis-din il-klassi.

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Kif tkun taf tara matul il-ġimgħat li ġejjin, għandna differenti

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binarji għall-isfond lura diverġenti, sezzjonijiet għal dawk

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anqas komdu, aktar komda, dawk x'imkien

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bejniethom.

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Kif tkun taf tara dan il-weekend u ġimgħa d-dieħla, żewġ verżjonijiet tal-

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settijiet aktar problema fil edizzjoni standard u Hacker tnejn hekk

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li intom kollha tista 'tagħżel awto-fit-triq magħhom inti

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huma l-aktar komdu.

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>> Allura llum, aħna adsa fis din il-programmazzjoni

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lingwa imsejħa Scratch.

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Huwa lingwa ta 'programmar grafika, u madankollu jkollha l-

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istess karatteristiċi ta 'wħud mill-lingwi ta' livell ogħla Aħna ser

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tesplora aktar tard fil-semestru, fosthom C u

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JavaScript u PHP.

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Iżda huwa għaddej biex inessu biex jevitaw xi wħud mill-distrazzjonijiet

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kmieni ta 'sintassi, affarijiet simili semicolons, parentesi,

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u dettalji arcane oħra li,-ewwel daqqa t'għajn, huma biss mhux

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fil-livelli kollha intellettwalment interessanti u għandhom tendenza li jiksbu fil-

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il-mod minn xi fehim fundamentali.

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F'termini ta 'issa l-istruttura ta' appoġġ qabel, realizzati dan

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għodda, CS50 Iddiskuti, li se jkunu marbuta fuq il-kors tal-

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websajt aktar tard illum, huwa l-forum ta 'diskussjoni onlajn fl-

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li inti ser tkun kapaċi li jistaqsu mistoqsijiet ta 'xulxin u

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persunal, u huwa wkoll għodda, kif aħna ser tara ġimgħa d-dieħla,

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li aħna ser tuża pjuttost integratedly fil

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uffiċċju siegħa kif ukoll.

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Tabilħaqq, ħinijiet jibda nhar it-Tnejn, u franchement, l-ewwel

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ġimgħa tal-ħinijiet tal-uffiċċju hija essenzjali pjuttost baxx.

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>> Ma naħsibx li inti ser issib Scratch kollu li inaċċessibbli.

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Huwa pjuttost ta 'spjegazzjoni, kif Ser naraw, u iva, liema

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aħna ser tagħmel użu minnha għal-lum huwa li estratt xi wħud mill-

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ideat fundamentali li se, imbagħad, jippersistu matul il-

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bqija tas-semestru.

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Iżda jibda Tnejn, fi 8:00 PM permezz 23:00 se jkun

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uffiċċju siegħa Annenberg aktar minn waqfa moħħ.

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Sezzjonali 2 se tibda illejla, hekk f'xi din

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weekend, mur cs50.net/section, u tkun taf

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jintalbu għadd ta 'mistoqsijiet.

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Fost dawn, kif tiddeskrivi tiegħek

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livell ta 'kumdità bħala ta' llum?

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M'hemm l-ebda hard, regola malajr dwar min huwa li barmil.

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Huwa biss il-tip ta 'ħaġa li inti probabilment taf jekk inti

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huma fost dawk l-anqas komdu jew mod ieħor.

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>> U issa, walkthroughs.

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L-ispeċifikazzjoni sett problema għal din il-ġimgħa, kemm standard

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u edizzjoni Hacker bl-istess mod, huwa online fuq cs50.net minn issa.

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U tkun taf tara li l-ewwel minn dawn edizzjonijiet, il-

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edizzjoni standard kull ġimgħa, hija akkumpanjata minn xi ħaġa li aħna

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sejħa walkthrough kodiċi, sessjoni immexxi minn wieħed mill-

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fellows tagħlim kors li jiggwidawk, jipprovdu

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suġġerimenti dwar, u inti tikseb jistabbilixxi triq partikolari meta niġu

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biex jibdew dawn is-settijiet problema.

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Allura ma 'kull wieħed minn dawn problema settijiet, jekk int qatt jixtiequ

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għalik innifsek fejn nista tibda, inti tibda ma 'dawn

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walkthroughs.

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U fil-fatt, ippermettili jintroduċu Zamyla Chan, dan

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is-sena ta 'tagħlim sħabi li se jkun qed imexxi kull

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waħda minn dawn walkthroughs.

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Zamyla?

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>> [Applause]

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ZAMYLA Chan: Oh, hi kulħadd,.

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Jisimni Zamyla.

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I'ma inġinerija junior jistudjaw fl Winthrop Kamra.

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Imma jien jippruvaw u tajbin fl kif ħafna korsijiet tax-xjenza tal-kompjuter kif I

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tista ', u huwa għalhekk li jien verament eċċitati li jkun qed imexxi din

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walkthroughs is-sena.

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Walkthroughs, għalija, kien parti essenzjali tal-CS50 tiegħi

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esperjenza.

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Matul il-walkthrough, għal kull p-sett, aħna ser jgħaddu

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il-problema stabbiliti flimkien, ħarsa fuq il-problemi, it-tip ta '

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jaqsmuhom up fis gdim maniġġabbli.

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I ser jagħtuk tips, tekniki, biex jinkiseb

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permezz ta 'u jkollna beda.

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Jien nittama li nara inti kollha fil-walkthroughs.

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Jekk inti ma tistax tagħmel dan fil-persuna, imbagħad

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jekk jogħġbok do tixgħel online.

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>> DAVID Malan:. Eċċellenti

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Grazzi, Zamyla.

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Allura jirrealizzaw li walkthroughs huma, fil-fatt, fuq il-ġimgħa

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wara nofsinhar, iżda dan huwa deliberatament permezz tad-disinn b'tali mod li

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anki jekk youd pjuttost ma jattendu klassi nhar ta 'Ġimgħa

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wara nofsinhar, il-videos se jkun f'idejn l-aktar malajr matul

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il-weekend.

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Allura jirrealizzaw li cs50.net se jkunu kollha ta 'l-Zamyla

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walkthroughs.

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U li hemm data tal-lum u l-ħin, 03:00,

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Harberd Hall, 104.

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U xi wħud mill-fellows tagħlim ppreparaw ukoll

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xi rimarki għalik in absentia biex jagħtuk daqsxejn ta '

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perspettiva dwar liema esperjenza tagħhom u l-bidu fis-

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għeluq ta 'CS50 kien simili.

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Mela jekk nistgħu dim-dwal għal ftit mument, I jagħtik

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xi wħud mill-persunal CS50 s.

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>> JACKSON STEINKAMP: I ħa CS50 aħħar sena bħala freshman fil-

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jaqgħu, u huwa assolutament nefaħ my mind.

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I qatt ma ħadet xi klassijiet ta 'programmazzjoni qabel,

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u qatt daħal ma 'kwalunkwe xjenza tal-kompjuter

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esperjenza fil-livelli kollha.

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U biss, Smajt il-buzz dwar il-klassi u

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ddeċieda li jieħu dan.

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>> Julia MITELMAN: Kien verament gost, tassew involviment.

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I għadhom, sal-lum -

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I biss reċentement raw Għandi l-floppy disk li David tana

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fl-ewwel jum tagħna ta 'lecture.

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I kien mdendla fuq ħajt tiegħi.

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Din hija probabbilment ftit nerdy, imma I mdendla fil dwar tiegħi

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ħajt matul il-klassi bħala tifkira ta 'kif jiksaħ kien.

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>> TRAVIS Downs: Huwa hekk imbarazzanti.

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>> JACKSON STEINKAMP: Computer xjenza hija xi ħaġa li għandek

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għandek tipprova anki jekk int ma wieħed għal

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ix-xjenzi tradizzjonali.

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Huwa l-esperjenza tagħha stess, u CS50 se tagħmel żgur li int

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appoġġjati ukoll permezz ta 'dan ma' l-armata vera tagħha ta 'TFS.

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>> ALI NAHM: I ħa bħala freshman, u so I magħmula ħafna

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ta 'ħbieb ġodda.

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I wkoll ltqajna introdotti għal dan konċentrazzjoni kollha u

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iskola kollu ta 'l-inġinerija, u so I jirrakkomanda ħafna dan

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u nilqgħek familja CS50 tagħna.

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>> Yaniv YACOBY: CS50 biss tgħallem kif għandek tuża għodda

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li huma ġeneralment aċċessibbli.

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Inti biss bżonn laptop, għandek bżonn web browser, u inti

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ħtieġa li jitgħallmu jiktbu xi kodiċi, u inti tista 'verament jibni

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affarijiet pulita.

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>> KAREN Xiao: Huwa biss hekk jibred biex ikunu jistgħu jagħmlu xi ħaġa

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u lin-nies jużawh u lin-nies jarawha, u li l-

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dak I really love dwar dan.

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>> TIM MCLAUGHLIN: - sens ta 'komunità, naħseb, f'dan

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aktar minn kull kors ieħor stajt meħuda s'issa kors.

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Int mhux biss tieħu ieħor -

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int ma timla ieħor rekwiżit.

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Int mhux biss ser lectures u tmur taqsima.

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Imma int tagħmel tunnellata ta 'affarijiet li huma kollha dwar

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ipprogrammar u kollha dwar it-teknoloġija, iżda ma

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verament jħossu bħal klassi maġġoranza tal-ħin.

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>> Downs Travis: U fl-ewwel jum, huma mogħtija barra kejk, u

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I kien istantanjament mibjugħa.

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>> JACOB PRITT: kandju Ħieles u pizza.

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>> ZAMYLA Chan: - x'inhu l-livell interess tiegħek, I think

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li CS50, inti ser ikollok gost, u tkun taf tkun intellettwalment

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stimulata.

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>> MARKA GROZEN-SMITH: Huwa dejjem parti fil-klassi, u huwa

194
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parti kull lejl li jaħdmu fuq tiegħek p-sett.

195
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>> JACKSON STEINKAMP: Kull darba li inti finitura sett problema, inti

196
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se jħossu bħal inti stajt lest proġett.

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>> Melissa Niu: Kien sena freshman, u I kien sar shopping.

198
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Kelli erba 'klassijiet tiegħi lesta, u I kien fil Annenberg.

199
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U jien bump fis xi ħabib, u huwa jgħid, ħej, jien shopping

200
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din il-klassi imsejħa CS50, u inti għandek come miegħi.

201
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Spiċċaw tieħdu li jaqgħu, u wara dik il-klassi, I

202
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ħsibt forsi jien ser minuri fil CS.

203
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Imma hawn I am, tliet snin wara, xorta jistudjaw kompjuter

204
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xjenza u fil-fatt jagħmlu dan bħala maġġuri, u I imħabba kull

205
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mument ta 'dan.

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>> ROB Bowden: Għandi l-ebda idea.

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>> ALI NAHM: Ejja naraw.

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>> Melissa Niu: craziness.

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>> SPEAKER 1: inħoss bħal I d jkun ħafna cliché.

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I d biss jgħidu, bħal, biża '.

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>> Yaniv YACOBY: Aċċessibilità.

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>> JACOB PRITT: kandju Ħieles u pizza.

213
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>> TRAVIS Downs: Ma jistgħux nirrifjuta klassi li l-idejn out kejk.

214
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>> TIM MCLAUGHLIN:. Enerġetiċi

215
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>> Vipul Shekhawat: Essenzjali.

216
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>> ROB Bowden: Let me think ta 'risposta.

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I think I ltqajna xi ħaġa.

218
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Oh, god.

219
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Yeah, jien jisimni Rob Bowden, u dan huwa CS50.

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>> [Applause]

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DAVID Malan: Kull dritt, hekk ejja tibda żebgħa stampa

222
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tad-direzzjoni li aħna tista 'tmur, u ejja jintroduċu

223
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dan il-kunċett hawnhekk magħrufa bħala pseudocode.

224
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Allura pseudocode mhix programmazzjoni

225
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lingwa unto innifsu.

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Huwa xejn tekniku per se, imma huwa biss tip ta '

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mod ġenerali ta 'tesprimi lilek innifsek pjuttost b'mod preċiż,

228
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pjuttost algorithmically, pjuttost proċeduralment, iżda mingħajr

229
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ma joqogħdu jinkwetaw dwar dak lingwa li qed jesprimu

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ruħek pulzieri

231
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Huwa xi mudell ta 'l-Ingliż u lingwi ta' programmar ma

232
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li jiġri li jkun familjari, hekk aħna tista 'tibda

233
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bil-miktub dan it-tip ta 'ħaġa kif immorru.

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U fil-fatt, Joseph, jista I tissellef inti up fuq il-palk li jkunu

235
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scribe hawn?

236
00:10:55,490 --> 00:11:00,130
Stajt marret quddiem hawn bil-quddiem u minsija li jpoġġu

237
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fuq xi kalzetti llum, u dan ser ikun fost aktar tagħna

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eżempji redikoli.

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>> Issa, I bżonn inti hawn fuq.

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I ser tagħmel il-parti kalzetti.

241
00:11:05,630 --> 00:11:08,040
Allura hawnhekk għandna pad scratch ftit.

242
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Dan huwa litteralment biss TextEdit fil Mac.

243
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Aħna mhux fil-fatt se jikteb programm Runnable, iżda

244
00:11:12,270 --> 00:11:14,220
aħna qed biss ser tibda Skeċċjar l ibbażata pseudocode

245
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fuq xi wħud mill-avukat inti tipprovdi lili hawn.

246
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Allura hawnhekk huwa pile tiegħi ta 'kalzetti fid-dar.

247
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Għandi l-ebda kalzetti fuq meta I jinxtegħel fil-għodu, u aħna issa

248
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ħtieġa li jikteb programm, algoriżmu ta 'tipi, li magħhom

249
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biex tikseb dawn kalzetti fuq saqajn tiegħi.

250
00:11:27,900 --> 00:11:30,860
U tul it-triq, ejja ara jekk irridu vjaġġ fuq, jew tiltaqa 'ma,

251
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xi wħud mill-ideat li int ser ikollhom jibdew

252
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ħsieb dwar ħafna aktar serjament meta jipprogrammaw

253
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lest programmi tiegħek ma jaġixxix pjuttost kif maħsub.

254
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>> So I joqogħdu bilqegħda hawn.

255
00:11:39,580 --> 00:11:41,180
Stajt ltqajna munzell tiegħi ta 'kalzetti.

256
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X'inhu l-ewwel ħaġa bniedem raġonevoli kieku

257
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do meta l-għan huwa li jitpoġġew fuq par kalzetti?

258
00:11:46,600 --> 00:11:49,190
Xi ħadd jagħti me pass wieħed, u wieħed biss pass.

259
00:11:49,190 --> 00:11:49,796
Yeah?

260
00:11:49,796 --> 00:11:50,690
UDJENZA: Ilwi l isfel.

261
00:11:50,690 --> 00:11:54,290
DAVID Malan: Ilwi l isfel, Okay.

262
00:11:54,290 --> 00:11:55,540
Pass 2.

263
00:11:59,975 --> 00:12:00,645
Pass 2.

264
00:12:00,645 --> 00:12:01,840
UDJENZA: Aqbad suletta tiegħek.

265
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DAVID Malan: Aqbad suletta tiegħek.

266
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Okay, l-ambigwità tant żgħira hawn, u dan huwa wieħed mill-ewwel

267
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xkiel blokki li aħna qed suppost deliberatament

268
00:12:09,380 --> 00:12:10,290
jiltaqgħu hawn.

269
00:12:10,290 --> 00:12:14,110
Huwa ftit ambigwa, hekk pick up suletta tiegħek.

270
00:12:14,110 --> 00:12:17,425
Fine, jien ser tieħu dan wieħed, imma kompjuter, tirrealizza fi ftit

271
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bit, mhux se jkollhom dik it-tip ta 'istint tal-bniedem għal ftit

272
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pick-eqreb wieħed.

273
00:12:21,490 --> 00:12:23,590
Aħna ser ikollhom jibdew, qabel twil, jesprimu

274
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nfusna b'mod aktar preċiż.

275
00:12:24,610 --> 00:12:26,600
>> Kull dritt, hekk pass 2 huwa pick up suletta tiegħek.

276
00:12:26,600 --> 00:12:27,520
Aħna ser teħodha.

277
00:12:27,520 --> 00:12:28,620
Pass 3.

278
00:12:28,620 --> 00:12:29,532
Fil-dahar.

279
00:12:29,532 --> 00:12:30,900
UDJENZA: Sib par tqabbil.

280
00:12:30,900 --> 00:12:32,060
DAVID Malan: Sib par tqabbil.

281
00:12:32,060 --> 00:12:34,740
Okay, għalhekk dan huwa tajjeb.

282
00:12:34,740 --> 00:12:35,650
I kellhom jagħżlu dan suletta.

283
00:12:35,650 --> 00:12:39,200
Allura l-għan huwa li tinstab suletta tqabbil, issa, imma dak

284
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jfisser?

285
00:12:39,990 --> 00:12:42,130
A bniedem raġonevoli li, ferm simili l-Erbgħa meta I biss

286
00:12:42,130 --> 00:12:44,700
kien jaf kif issib Mike Smith fil-ktieb tat-telefon, biss tip ta '

287
00:12:44,700 --> 00:12:45,640
marru ma istint tagħhom.

288
00:12:45,640 --> 00:12:49,220
Iżda hawnhekk, huwa ovvjament dan suletta hawn, iżda tal-kompjuter

289
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mhux se jkun hekk istintiv.

290
00:12:51,350 --> 00:12:53,830
A kompjuter huwa se jkollu ġabra ta 'bits, kif aħna

291
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diskussi nhar l-Erbgħa, u dawk li huma

292
00:12:55,380 --> 00:12:56,710
organizzata b'xi fil-memorja.

293
00:12:56,710 --> 00:13:00,400
Iżda l-punt huwa li l-kompjuter għandha biss il-kapaċità

294
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li tħares lejn l-affarijiet wieħed fi żmien, u fil-fatt, anki aħna

295
00:13:03,390 --> 00:13:05,980
bnedmin - anki jekk tħoss bħal I glanced isfel u qasma

296
00:13:05,980 --> 00:13:08,900
2 tard Naf fejn il-suletta hija, moħħ tiegħi u l-għajnejn tiegħi

297
00:13:08,900 --> 00:13:12,000
preżumibbilment ma a quick skim ta 'dawk kalzetti, u mbagħad maqfula

298
00:13:12,000 --> 00:13:13,400
fuq il-wieħed fil-kwistjoni.

299
00:13:13,400 --> 00:13:15,780
>> Allura jekk aħna tkun l-aktar intenzjonat issa bħala kompjuter,

300
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kif nista 'nsib dan il-par tqabbil?

301
00:13:17,780 --> 00:13:18,890
Ukoll, irridu jtenni.

302
00:13:18,890 --> 00:13:21,440
Irridu forsi loop matul dan mess ta 'kalzetti fuq il-

303
00:13:21,440 --> 00:13:25,760
art fejn I ngħid xi ħaġa simili GĦAL KULL suletta, pick it

304
00:13:25,760 --> 00:13:30,195
up, U JEKK l-istess forma u daqs bħala l-ieħor, imbagħad

305
00:13:30,195 --> 00:13:32,150
dot, dot, dot, aħna ser tkompli l-istorja.

306
00:13:32,150 --> 00:13:34,430
Allura għal kull suletta, so I pick up dan wieħed.

307
00:13:34,430 --> 00:13:36,520
I check hija din ugwali għal dan wieħed.

308
00:13:36,520 --> 00:13:38,250
Mhuwiex, so I twarrab ġenb.

309
00:13:38,250 --> 00:13:39,220
Imbagħad I jtenni mill-ġdid.

310
00:13:39,220 --> 00:13:40,340
Huwa dan wieħed ugwali?

311
00:13:40,340 --> 00:13:42,010
Le, mhuwiex, so I poġġih aside.

312
00:13:42,010 --> 00:13:42,710
Huwa dan wieħed?

313
00:13:42,710 --> 00:13:43,200
No

314
00:13:43,200 --> 00:13:43,670
Dan wieħed?

315
00:13:43,670 --> 00:13:44,520
Le, u oħrajn.

316
00:13:44,520 --> 00:13:48,730
U mbagħad finalment, wieħed jittama, I se jiltaqgħu ma 'din suletta hawn.

317
00:13:48,730 --> 00:13:51,350
Mela jekk huwa l-istess għamla, daqs, teħodha.

318
00:13:51,350 --> 00:13:53,980
>> U issa, x'għandhom ikunu pass li jmiss tagħna hawn?

319
00:13:53,980 --> 00:13:54,402
Yeah?

320
00:13:54,402 --> 00:13:56,090
UDJENZA: Identifika dritt mix-xellug.

321
00:13:56,090 --> 00:13:58,980
DAVID Malan: Okay, jidentifikaw lemin u xellug, sabiex

322
00:13:58,980 --> 00:14:01,870
fortunatament, dan it-tip ta 'xogħlijiet.

323
00:14:01,870 --> 00:14:04,020
A simetriċi ftit, jew stajt biss jintlibsu lilhom dak il-mod.

324
00:14:04,020 --> 00:14:07,020
Kull dritt, hekk stajt identifikat il-lemin.

325
00:14:07,020 --> 00:14:09,980
U issa, qabel we tipproċedi, let me punt dak Ġużepp

326
00:14:09,980 --> 00:14:12,890
qed tagħmel hawn bħala tip ta 'programmer versed.

327
00:14:12,890 --> 00:14:15,800
Għalhekk għal darb'oħra, hemm ebda mod wieħed kif isir dan, imma lil hinn minn sempliċiment

328
00:14:15,800 --> 00:14:18,480
numerazzjoni il-linji, Joseph diġà bdew jagħmlu dan

329
00:14:18,480 --> 00:14:19,460
tip ta 'indentazzjoni.

330
00:14:19,460 --> 00:14:21,950
Tabilħaqq, dan huwa konvenzjoni komuni ħafna fl-ipprogrammar,

331
00:14:21,950 --> 00:14:26,110
fejn meta inti tagħmel xi ħaġa iterattiv, looping stil, kif

332
00:14:26,110 --> 00:14:28,480
aħna qed timplika bil-frażi Ingliża "GĦAL KULL

333
00:14:28,480 --> 00:14:31,090
suletta, "il-konvenzjoni pseudocode u, kif aħna ser tara,

334
00:14:31,090 --> 00:14:33,410
lingwi normali ta 'programmazzjoni, huwa biss inċiż.

335
00:14:33,410 --> 00:14:36,240
Hit-ispazju bar għal xi ftit drabi, laqat il-ewlenin Tab jew simili,

336
00:14:36,240 --> 00:14:40,660
b'tali mod li nested taħt "GĦAL KULL suletta" hija l-blokki ta '

337
00:14:40,660 --> 00:14:43,430
Jittieħed li għandek bżonn tagħmel bħala riżultat ta 'dak loop.

338
00:14:43,430 --> 00:14:45,940
Allura dak kollu li jwasslu semantikament.

339
00:14:45,940 --> 00:14:48,620
Issa sadanittant, il-"Jekk huwa l-istess forma u daqs," il-

340
00:14:48,620 --> 00:14:51,590
fatt li "Ħudu" hija inċiża wkoll ifisser biss

341
00:14:51,590 --> 00:14:54,370
dan huwa l-unika ħaġa li għandek tagħmel jekk din il-kundizzjoni,

342
00:14:54,370 --> 00:14:59,770
jekk dik il-fergħa, li furketta fit-triq, huwa fil-fatt veru.

343
00:14:59,770 --> 00:15:02,130
>> Allura issa hawn, aħna qed dwar il-pass 4, jidentifikaw lemin u xellug.

344
00:15:02,130 --> 00:15:03,410
Stajt identifikat id-dritt.

345
00:15:03,410 --> 00:15:05,150
Agħti me pass 5.

346
00:15:05,150 --> 00:15:07,880
U teknikament, nistgħu verament sejħa

347
00:15:07,880 --> 00:15:09,510
l GĦAL KULL ħaġa -

348
00:15:09,510 --> 00:15:11,450
inti għandek probabbilment jinnumera l-linji jekk

349
00:15:11,450 --> 00:15:12,190
aħna qed tmur biex tagħmel dan.

350
00:15:12,190 --> 00:15:14,006
JOSEPH: [inaudible]

351
00:15:14,006 --> 00:15:14,610
DAVID Malan: [inaudible]?

352
00:15:14,610 --> 00:15:16,070
Okay, multa, id-dritt, aħna ser tagħmel dan tiegħek mod.

353
00:15:16,070 --> 00:15:19,590
Kull dritt, hekk pass 5, kif nistgħu nagħmlu l-suletta dritt?

354
00:15:19,590 --> 00:15:22,310
Kif nistgħu tipproċedi jmiss, hawn?

355
00:15:22,310 --> 00:15:22,730
Iva?

356
00:15:22,730 --> 00:15:24,300
UDJENZA: Lift up riġel tal-lemin.

357
00:15:24,300 --> 00:15:27,100
DAVID Malan: Lift up riġel tal-lemin, Okay.

358
00:15:27,100 --> 00:15:29,330
Pass 6?

359
00:15:29,330 --> 00:15:30,728
Malajr.

360
00:15:30,728 --> 00:15:31,202
Yeah.

361
00:15:31,202 --> 00:15:33,100
UDJENZA: Sib tarf miftuħ tal-suletta.

362
00:15:33,100 --> 00:15:34,440
DAVID Malan: Okay, issib it-tarf miftuħ tal-suletta.

363
00:15:34,440 --> 00:15:34,840
Allura tajjeb.

364
00:15:34,840 --> 00:15:37,180
Allura hawn, onestament, l-istint komuni ħafna se jkun biss

365
00:15:37,180 --> 00:15:39,880
jitqiegħdu fuq suletta dritt, iżda li wisq huwa pjuttost ambigwu.

366
00:15:39,880 --> 00:15:42,750
Sakemm il-kompjuter jew bniedem jaf eżattament dak li tfisser,

367
00:15:42,750 --> 00:15:45,160
huwa mhuwiex ser ikun li tesegwixxi li, hekk hawn, stajt

368
00:15:45,160 --> 00:15:46,520
sabet li l-ftuħ ta 'l-istokk.

369
00:15:46,520 --> 00:15:48,222
Pass 7?

370
00:15:48,222 --> 00:15:49,700
UDJENZA: Touch għajnen tiegħek.

371
00:15:49,700 --> 00:15:51,070
DAVID Malan: sieq Touch.

372
00:15:51,070 --> 00:15:53,546
Okay, hekk issa we go -

373
00:15:53,546 --> 00:15:56,480
Kull dritt, jien ser jieħdu xi libertajiet hawn.

374
00:15:56,480 --> 00:15:57,110
Grazzi.

375
00:15:57,110 --> 00:15:59,210
Pass 8?

376
00:15:59,210 --> 00:16:00,060
Poġġi fuq suletta.

377
00:16:00,060 --> 00:16:02,060
Okay, hekk issa I, think we qed qrib biżżejjed biex issolvi tad tieħu

378
00:16:02,060 --> 00:16:03,480
dan wieħed fid-dar.

379
00:16:03,480 --> 00:16:05,980
Kull dritt, għalhekk dan imur up.

380
00:16:05,980 --> 00:16:07,950
I ser tieħu xi libertajiet ma 'dak li jfisser, fil-fatt.

381
00:16:07,950 --> 00:16:08,920
Poġġi l-suletta fuq.

382
00:16:08,920 --> 00:16:10,853
Kull dritt, issa pass 9?

383
00:16:10,853 --> 00:16:11,740
UDJENZA: Poġġi sieq isfel.

384
00:16:11,740 --> 00:16:12,510
DAVID Malan: Grazzi.

385
00:16:12,510 --> 00:16:15,610
Pass 9, mressqa marda isfel, u issa, aħna tista 'tirrepeti.

386
00:16:15,610 --> 00:16:19,540
Allura preżumibbilment, nistgħu issa tmur fil-pass 10 u jgħidu jidentifikaw

387
00:16:19,540 --> 00:16:21,960
xellug suletta, iżda li preżumibbilment diġà sar.

388
00:16:21,960 --> 00:16:24,100
>> U hekk imbagħad, nista sort ta irreperti dawn il-passi.

389
00:16:24,100 --> 00:16:25,260
Iżda dan it-tip ta 'iqajjem il-kwistjoni.

390
00:16:25,260 --> 00:16:28,100
Qabel, l-aħħar darba ridna li jirrepetu xi ħaġa, aħna

391
00:16:28,100 --> 00:16:30,730
ma kien iteratively, għal darb'oħra u għal darb'oħra, a GĦALL

392
00:16:30,730 --> 00:16:32,660
KULL loop biex ngħidu hekk.

393
00:16:32,660 --> 00:16:36,420
Ikun jagħmel sens li tuża loop sabiex jimmaniġġjaw kemm

394
00:16:36,420 --> 00:16:38,470
ix-xellug u l-suletta dritt?

395
00:16:38,470 --> 00:16:40,460
Minħabba li jħoss simili dawn l-operazzjonijiet huma pjuttost ħafna

396
00:16:40,460 --> 00:16:43,090
identika ħlief għall-fatt li wieħed jibda hawn u wieħed

397
00:16:43,090 --> 00:16:44,850
tibda hawn?

398
00:16:44,850 --> 00:16:47,400
Do we loop, jew nistgħu biss iżommu passi bil-miktub

399
00:16:47,400 --> 00:16:48,745
10 u 11 u 12?

400
00:16:48,745 --> 00:16:50,540
UDJENZA:. Loop

401
00:16:50,540 --> 00:16:52,240
>> DAVID Malan: Okay, hekk loop.

402
00:16:52,240 --> 00:16:54,730
I attwalment jista 'jkollhom qal biss iżommu għaddejjin.

403
00:16:54,730 --> 00:16:55,720
Allura għaliex huwa dan il-każ?

404
00:16:55,720 --> 00:16:57,940
Ukoll, dan huwa fil-fatt l-ewwel ta 'tagħna mhux ovvju

405
00:16:57,940 --> 00:17:01,210
deċiżjonijiet tad-disinn, u fil-fatt, wieħed mill-metriċi li magħhom

406
00:17:01,210 --> 00:17:03,990
aħna ser jibdew jevalwaw, għalina u għalik, il-

407
00:17:03,990 --> 00:17:06,780
kwalità ta 'programm huwa kemm ukoll mfassla huwa.

408
00:17:06,780 --> 00:17:09,619
Have you jsir l-ammont ta 'xogħol meħtieġ minimu li

409
00:17:09,619 --> 00:17:12,480
x-xogħol isir l-aktar malajr, jew f'termini ta '

410
00:17:12,480 --> 00:17:15,430
ħin tiegħek jew f'termini ta 'running time tal-kompjuter?

411
00:17:15,430 --> 00:17:17,589
Kemm operazzjonijiet ma li tieħu biex tesegwixxi?

412
00:17:17,589 --> 00:17:20,180
Allura forsi, din hija opportunità għal loop minħabba

413
00:17:20,180 --> 00:17:22,829
malli nibda ikkupjar u pasta, bħala Joseph effettiv

414
00:17:22,829 --> 00:17:25,010
kieku jibdew jagħmlu fil-mument, int tip ta 'ħela tiegħek

415
00:17:25,010 --> 00:17:27,140
żmien, u int qed doppjament espressiva.

416
00:17:27,140 --> 00:17:30,260
>> Iżda fl-istess ħin, dawn huma verament biss żewġ speċjali

417
00:17:30,260 --> 00:17:31,890
każijiet, tax-xellug u tal-lemin.

418
00:17:31,890 --> 00:17:34,930
U billi qabel, I jista 'jkollhom 10 jew 20 jew aktar kalzetti

419
00:17:34,930 --> 00:17:37,960
munzell, huwa definittivament jagħmel sens li ma jkollhom 50-linji ta '

420
00:17:37,960 --> 00:17:40,180
Kodiċi qal tivverifika din suletta, allura dak li jmiss,

421
00:17:40,180 --> 00:17:41,300
allura dak li jmiss.

422
00:17:41,300 --> 00:17:43,450
Hawnhekk, huwa ftit inqas ovvji, u jien proposti

423
00:17:43,450 --> 00:17:44,390
li nistgħu jmorru jew mod.

424
00:17:44,390 --> 00:17:46,720
Aħna jista 'jkollhom jew li loop, għalkemm biss loops

425
00:17:46,720 --> 00:17:50,620
darbtejn, jew nistgħu sempliċiment kopja u paste biss ftit

426
00:17:50,620 --> 00:17:53,270
hawn biex x-xogħol isir.

427
00:17:53,270 --> 00:17:55,210
Iżda dan il-programm huwa Buggy, biex ngħidu hekk.

428
00:17:55,210 --> 00:17:59,120
Jista 'jkollha xi żbalji, żbalji, jew każijiet kantuniera, hekk li

429
00:17:59,120 --> 00:18:00,860
jitkellmu, li aħna ma verament tantiċipa.

430
00:18:00,860 --> 00:18:03,400
Xejn li marret ħażin dan iż-żmien, imma dak setgħet marret ħażin

431
00:18:03,400 --> 00:18:06,100
filwaqt li jesegwixxi dan il-programm?

432
00:18:06,100 --> 00:18:07,040
UDJENZA: Inti ma għandekx xi kalzetti.

433
00:18:07,040 --> 00:18:08,980
>> DAVID Malan: Allura jista 'jkun hemm l-ebda kalzetti hemmhekk tkun xi tkun.

434
00:18:08,980 --> 00:18:10,380
Mela ejja jikkunsidraw il-każ kantuniera.

435
00:18:10,380 --> 00:18:14,670
Mela jekk nistgħu iscroll lura sa pass wieħed, hekk pass wieħed kien

436
00:18:14,670 --> 00:18:16,540
liwja isfel, biex din kontrolli out.

437
00:18:16,540 --> 00:18:21,250
Pass 2, pick up suletta tiegħek, iżda mbagħad issib suletta tqabbil,

438
00:18:21,250 --> 00:18:22,420
jidentifikaw id-dritt.

439
00:18:22,420 --> 00:18:25,050
Aħna tip ta magħmula mazz sħiħ ta 'suppożizzjonijiet, u dan huwa,

440
00:18:25,050 --> 00:18:27,720
franchement, għaliex il-programm kultant crash.

441
00:18:27,720 --> 00:18:30,240
Jekk inti, il-programmer, għamlu ċerti suppożizzjonijiet, bħal

442
00:18:30,240 --> 00:18:33,000
żgur hemm għaddej li jkun kalzetti jew żgur hemm għaddej

443
00:18:33,000 --> 00:18:35,310
li jkun memorja jitħalla fil-kompjuter, żgur hemm għaddej

444
00:18:35,310 --> 00:18:37,420
li jkun hemm spazju disk jitħalla fuq il-hard drive -

445
00:18:37,420 --> 00:18:39,040
Ukoll, jekk inti tagħmel dawn is-suppożizzjonijiet, u li mhux,

446
00:18:39,040 --> 00:18:41,880
fil-fatt, ir-realtà, li jaf xi kultant dak tal-kompjuter

447
00:18:41,880 --> 00:18:42,520
se jagħmlu?

448
00:18:42,520 --> 00:18:44,450
U xi kultant, meta ikollok l-ballun bajja għażil jew l-

449
00:18:44,450 --> 00:18:47,750
Windows iffriżat jew simili, li preċiżament minħabba xi

450
00:18:47,750 --> 00:18:50,980
programmer ma tantiċipa dawk il-każijiet kantuniera hekk imsejħa.

451
00:18:50,980 --> 00:18:53,050
X'aktar setgħet marret ħażin f'dan il-programm?

452
00:18:53,050 --> 00:18:53,330
Yeah?

453
00:18:53,330 --> 00:18:55,950
>> UDJENZA: Inti ma għandekx riġel tal-lemin u riġel tax-xellug.

454
00:18:55,950 --> 00:18:58,920
DAVID Malan: Okay, jista 'ma jkollhomx kemm riġel tal-lemin u

455
00:18:58,920 --> 00:19:01,940
riġel tax-xellug, u għalhekk dan il-programm tista 'ma tkunx universalment

456
00:19:01,940 --> 00:19:02,590
applikabbli.

457
00:19:02,590 --> 00:19:03,658
Oħrajn?

458
00:19:03,658 --> 00:19:05,650
UDJENZA: Inti jista 'jkollok telgħet suletta orfni.

459
00:19:05,650 --> 00:19:07,970
DAVID Malan: I jista 'jkollhom telgħet suletta orfni, so a

460
00:19:07,970 --> 00:19:11,250
mhux tqabbil suletta li biss għandha l-ebda aħwa għaliex stajt

461
00:19:11,250 --> 00:19:13,650
mitlufa, huwa mqatta, huwa fil-ħasil xorta, jew simili.

462
00:19:13,650 --> 00:19:15,550
Allura li, ukoll, ma verament ġie ttrattat.

463
00:19:15,550 --> 00:19:15,790
Yeah?

464
00:19:15,790 --> 00:19:17,510
UDJENZA: Inti tista 'diġà għandhom kalzetti fuq.

465
00:19:17,510 --> 00:19:19,050
DAVID Malan: I jista 'diġà jkollhom kalzetti fuq.

466
00:19:19,050 --> 00:19:20,080
I ma attwalment check.

467
00:19:20,080 --> 00:19:23,350
JEKK inti ma għandekx kalzetti fuq, imbagħad tipproċedi biex tagħmel

468
00:19:23,350 --> 00:19:24,330
Linja wieħed u tnejn.

469
00:19:24,330 --> 00:19:24,980
U li jista 'jiġri.

470
00:19:24,980 --> 00:19:26,880
Inti torqod bil kalzetti tiegħek fuq u simili, sabiex

471
00:19:26,880 --> 00:19:28,860
li, wisq, każ kantuniera raġonevoli ħafna.

472
00:19:28,860 --> 00:19:29,630
U forsi wieħed ieħor?

473
00:19:29,630 --> 00:19:31,310
UDJENZA: Il-suletta huwa ġewwa barra.

474
00:19:31,310 --> 00:19:34,000
DAVID Malan: Allura l-suletta huwa ġewwa barra, hekk għamilna l-ebda żball

475
00:19:34,000 --> 00:19:35,330
verifika, fil-qosor.

476
00:19:35,330 --> 00:19:38,550
Aħna ma jiċċekkja jekk l-istat tad-dinja huwa kif aħna nistennew.

477
00:19:38,550 --> 00:19:41,310
Aħna ma jiċċekkjaw jekk aħna verament sabu dak li aħna qed tfittex.

478
00:19:41,310 --> 00:19:43,310
>> U anke jekk din hija tip ta 'eżempju redikoli

479
00:19:43,310 --> 00:19:46,110
jinvolvu kalzetti, fl-aħħar tal-ġurnata, dan huwa eżattament il-

480
00:19:46,110 --> 00:19:48,740
tip ta 'mentalità inti jeħtieġ li jkollhom waqt miktub programmi,

481
00:19:48,740 --> 00:19:51,740
anki fil Scratch kif ukoll fl-C, JavaScript, fil-PHP,

482
00:19:51,740 --> 00:19:53,920
għaliex inkella, programmi tiegħek se juru l-

483
00:19:53,920 --> 00:19:56,980
ekwivalenti ta 'dak ball bajja għażil jew biss jagħtu

484
00:19:56,980 --> 00:19:58,210
riżultati eżatti.

485
00:19:58,210 --> 00:20:00,250
Grazzi tant hawn għall scribe Joseph tagħna.

486
00:20:00,250 --> 00:20:05,060
[Applause]

487
00:20:05,060 --> 00:20:06,850
>> DAVID Malan: Kull dritt, iva, liema huwa, fil-

488
00:20:06,850 --> 00:20:08,230
fatt, programm tal-kompjuter?

489
00:20:08,230 --> 00:20:09,670
Ukoll, ejja tieħu t'għajn malajr fil-

490
00:20:09,670 --> 00:20:11,100
rappreżentant wieħed hawn.

491
00:20:11,100 --> 00:20:15,260
Allura dan huwa programm miktub b'lingwa imsejjaħ C. Ċ hija

492
00:20:15,260 --> 00:20:17,830
lingwi pjuttost qodma dawn il-ġranet, iżda ħafna aktar ġodda huma mibnija

493
00:20:17,830 --> 00:20:18,460
fuq quċċata ta 'dan.

494
00:20:18,460 --> 00:20:21,180
Tabilħaqq, PHP, waħda mil-lingwi tal-web iċċentrati Aħna ser

495
00:20:21,180 --> 00:20:24,050
jużaw lejn tmiem tul ta 'min, fih innifsu jkun dak li sejjaħ għal

496
00:20:24,050 --> 00:20:27,550
interpretu, programm li bil-miktub fis-C, iżda aktar fuq dik

497
00:20:27,550 --> 00:20:28,690
fil-ġimgħat f'ħafna minn issa.

498
00:20:28,690 --> 00:20:30,840
Iżda dan il-programm, u dan huwa dak li tfisser li jiktbu

499
00:20:30,840 --> 00:20:32,880
programm, għalkemm wieħed sempliċi ħafna.

500
00:20:32,880 --> 00:20:35,540
Għandna xi sintassi pjuttost mistur hawn, imma int tista '

501
00:20:35,540 --> 00:20:38,340
probabbilment raden, anki jekk inti stajt qatt programmati qabel, liema

502
00:20:38,340 --> 00:20:39,750
dan il-programm ma.

503
00:20:39,750 --> 00:20:43,640
Tabilħaqq, I do not know dak printf hu, iżda jistampa ċertament

504
00:20:43,640 --> 00:20:45,700
conjures l-idea ta 'l-istampar xi ħaġa barra.

505
00:20:45,700 --> 00:20:48,590
U hekk iva, dan il-programm huwa finalment se jistampa

506
00:20:48,590 --> 00:20:50,250
il-kliem "Hello, Dinja."

507
00:20:50,250 --> 00:20:53,390
>> Issa, jekk għandek Mac jew PC jew kompjuter Linux, odds

508
00:20:53,390 --> 00:20:55,550
huma, għall-inqas jekk inti jitniżżel xi liberament

509
00:20:55,550 --> 00:20:58,000
software disponibbli, inti tista ġew miktub programmi fuq

510
00:20:58,000 --> 00:21:00,310
laptop tiegħek għal żmien pjuttost twil issa.

511
00:21:00,310 --> 00:21:03,040
Fuq Mac OS, per eżempju, hemm dan il-programm imsejjaħ

512
00:21:03,040 --> 00:21:05,340
Terminal li jiġi ma 'Mac, li normalment fl tiegħek

513
00:21:05,340 --> 00:21:07,550
Utilitajiet folder, u dan ġeneralment tiftaħ iswed u

514
00:21:07,550 --> 00:21:09,820
abjad jew tieqa abjad u iswed li fih inti għandek

515
00:21:09,820 --> 00:21:11,410
pront fejn inti tista tip jikkmanda.

516
00:21:11,410 --> 00:21:13,060
Allura dan huwa attwalment reminixxenti tal-kompjuters liema

517
00:21:13,060 --> 00:21:15,100
użati biex tkun qabel grafika user

518
00:21:15,100 --> 00:21:16,710
interfaces, GUIs, wasslilna.

519
00:21:16,710 --> 00:21:19,200
Issa, fil-Windows, inti għandek mekkaniżmu simili fil-forma

520
00:21:19,200 --> 00:21:20,130
tal-pront kmand.

521
00:21:20,130 --> 00:21:23,430
>> Imma dak li jien ser tagħmel hawnhekk hija tiftaħ, ejja ngħidu,

522
00:21:23,430 --> 00:21:26,580
TextEdit darb'oħra, hekk l-istess programm konna jużaw għall

523
00:21:26,580 --> 00:21:28,870
pseudocode mument ilu, u jien ser jimxi 'l quddiem u

524
00:21:28,870 --> 00:21:30,080
jiktbu program tiegħi ewwel.

525
00:21:30,080 --> 00:21:34,030
Inkludi stdio.h, tkun xi tkun li tfisser, int prinċipali

526
00:21:34,030 --> 00:21:36,880
null, tkun xi tkun li tfisser, u mbagħad fin-nofs hawn,

527
00:21:36,880 --> 00:21:40,560
printf ("bonjour, dinja."). U mbagħad mill-qrib kwotazzjoni,

528
00:21:40,560 --> 00:21:42,340
qrib paren, virgola.

529
00:21:42,340 --> 00:21:44,460
Issa jien ser jimxi 'l quddiem u biss hit Kmand-S. Jien ser

530
00:21:44,460 --> 00:21:47,650
biex jimxi 'l quddiem u ħlief dan bħala hello.c, sabiex il-konvenzjoni

531
00:21:47,650 --> 00:21:50,530
id-dinja ta 'programmar C huwa l-isem tal-fajl c dot.

532
00:21:50,530 --> 00:21:52,880
Jien ser biss jitqiegħed fil-direttorju dar John Harvard,

533
00:21:52,880 --> 00:21:56,370
hawn, ikklikkja Save, u issa jien se jmorru fuq għal dan

534
00:21:56,370 --> 00:21:59,110
tieqa terminal, li għal darb'oħra huwa dan pront iswed u abjad

535
00:21:59,110 --> 00:22:00,860
fejn I tista 'tesegwixxi jikkmanda.

536
00:22:00,860 --> 00:22:04,550
>> I tista 'taħdem programmi billi jittajpja l-isem tagħhom, mhux billi

537
00:22:04,550 --> 00:22:06,710
double-tikklikkja ikoni fis-sens tas-soltu.

538
00:22:06,710 --> 00:22:10,590
Imma l-ħaġa hija dwar C hija li lingwa bħal C 1

539
00:22:10,590 --> 00:22:13,150
taqa f'din il-forma, xi ħaġa imsejħa kodiċi sors.

540
00:22:13,150 --> 00:22:15,400
Xi ħaġa li jistenna ftit simili Ingliż imma hi

541
00:22:15,400 --> 00:22:17,980
definittivament inqas bħal Ingliż minn pseudocode Ġużepp

542
00:22:17,980 --> 00:22:18,930
mument ilu.

543
00:22:18,930 --> 00:22:20,560
Huwa ftit aktar arcane.

544
00:22:20,560 --> 00:22:22,830
Jidher li jsegwu xi mudelli jew regoli.

545
00:22:22,830 --> 00:22:25,300
Il-fatt li għandi ċineg kaboċċi, semicolons, kwotazzjonijiet,

546
00:22:25,300 --> 00:22:28,240
braces angolu, jħoss bħal kompjuter ħarāet bil din

547
00:22:28,240 --> 00:22:29,250
tip ta 'lingwa.

548
00:22:29,250 --> 00:22:32,010
Imma jekk immur, issa, għal dan tieqa terminal, I tista 'taħdem

549
00:22:32,010 --> 00:22:35,250
kmand li għaddej biex jikkonverti dak il-kodiċi ta 'sors

550
00:22:35,250 --> 00:22:36,610
xi ħaġa imsejħa kodiċi ta 'oġġett.

551
00:22:36,610 --> 00:22:39,690
Li għaddej biex jikkonvertu l-Ingliż bħall-sintassi li żerijiet

552
00:22:39,690 --> 00:22:41,760
u dawk, l-istess xorta ta żero u dawk aħna

553
00:22:41,760 --> 00:22:42,820
tkellem dwar l-Erbgħa.

554
00:22:42,820 --> 00:22:44,810
Issa, jien ser tmexxi kmand imsejjaħ clang.

555
00:22:44,810 --> 00:22:47,750
Aktar dwar dan fil-ġimgħat li ġejjin, iżda huwa programm bi

556
00:22:47,750 --> 00:22:52,330
li nista jikkonvertu hello.c fis-mazz sħiħ

557
00:22:52,330 --> 00:22:53,640
ta 'żero u dawk.

558
00:22:53,640 --> 00:22:54,950
>> Issa, stajt run dan il-kmand.

559
00:22:54,950 --> 00:22:57,940
Stajt run clang, u mbagħad I qal jimxu lilek innifsek fuq dan il-fajl

560
00:22:57,940 --> 00:23:00,630
imsejħa hello.c, li I ħolqot mument ilu, u

561
00:23:00,630 --> 00:23:02,090
xejn jidher li jiġri.

562
00:23:02,090 --> 00:23:05,550
Iżda fil-fatt, jekk I poked madwar id-direttorju dar tiegħi, jiena nara

563
00:23:05,550 --> 00:23:09,620
li dan il-programm a.out stupidly jismu issa teżisti.

564
00:23:09,620 --> 00:23:12,250
Dan huwa biss l-isem default għal programm meta tikteb fil

565
00:23:12,250 --> 00:23:15,140
C. Nistgħu jiskarta dan eventwalment, iżda a.out huwa l-

566
00:23:15,140 --> 00:23:18,340
isem tal-programm I biss konvertita żero u dawk.

567
00:23:18,340 --> 00:23:21,490
U issa li l-żerijiet huwa s u dawk, Mac tiegħi, f'dan il-każ, jew

568
00:23:21,490 --> 00:23:24,670
PC Windows tiegħek, tista 'tifhem dawk bits, dawk

569
00:23:24,670 --> 00:23:25,410
żero u dawk.

570
00:23:25,410 --> 00:23:29,130
U hekk meta I hit Ikteb, I ara "hello, dinja!"

571
00:23:29,130 --> 00:23:31,270
>> Imma hija Buggy daqsxejn.

572
00:23:31,270 --> 00:23:34,110
I ma pjuttost jgħidu "bonjour dinja,: arja: -! Jharvard." Bl-ajru huwa

573
00:23:34,110 --> 00:23:35,020
l-isem tal-kompjuter tiegħi.

574
00:23:35,020 --> 00:23:37,730
Jharvard l-isem tal-kont, iva, liema ma I b'mod ċar

575
00:23:37,730 --> 00:23:41,070
jħalli barra mill-programm?

576
00:23:41,070 --> 00:23:42,480
Xi tip ta 'waqfa linja.

577
00:23:42,480 --> 00:23:45,150
I ma hit l-ekwivalenti ta Ikteb jew il-ġarr ritorn,

578
00:23:45,150 --> 00:23:47,760
u dan huwa, għal darb'oħra, xhieda tal-fatt li l-kompjuters tista '

579
00:23:47,760 --> 00:23:49,800
biss tagħmel dak li jgħidulhom li jagħmlu.

580
00:23:49,800 --> 00:23:52,400
U l-fatt li jien ma tgħid il-kompjuter jimxu l-

581
00:23:52,400 --> 00:23:53,860
cursor għal-linja li jmiss -

582
00:23:53,860 --> 00:23:55,200
ukoll, huwa ċertament mhux se biss tagħmel dan

583
00:23:55,200 --> 00:23:56,750
presumptuously għalija.

584
00:23:56,750 --> 00:24:00,860
Mela jekk immur lura għall-programm tiegħi, u jien ngħid \ n -

585
00:24:00,860 --> 00:24:03,180
Allura \ N, kif aħna ser malajr tara, huwa l-mod ta '

586
00:24:03,180 --> 00:24:06,910
jirrappreżentaw affarijiet stramb bħal karattri linja ġodda, affarijiet

587
00:24:06,910 --> 00:24:08,840
li kieku tkun ir-riżultat ta '

588
00:24:08,840 --> 00:24:09,940
laqtu l-Enter.

589
00:24:09,940 --> 00:24:11,730
Iżda għal issa, biss jafu li laqtu l-Enter se

590
00:24:11,730 --> 00:24:14,170
biss tagħmel kodiċi tagħna ħarsa fard, sabiex id-dinja iddeċieda, inti taf

591
00:24:14,170 --> 00:24:16,580
dak, li żżomm affarijiet prettier, li dan jinżamm fuq linja waħda, ejja

592
00:24:16,580 --> 00:24:19,070
biss jgħidu \ N jirrappreżenta linja ġdida.

593
00:24:19,070 --> 00:24:22,260
Let me resave-fajl tiegħi, mur lura għall-tieqa terminal, u

594
00:24:22,260 --> 00:24:25,290
-ripetizzjoni a.out, Ikteb.

595
00:24:25,290 --> 00:24:28,374
Still Buggy, iżda għaliex?

596
00:24:28,374 --> 00:24:29,750
>> UDJENZA: [inaudible]

597
00:24:29,750 --> 00:24:31,540
DAVID Malan: Yeah, so I bżonn li recompile dan.

598
00:24:31,540 --> 00:24:34,610
Allura biex jikkompila programm sempliċiment ifisser jaqilbu mis-sors

599
00:24:34,610 --> 00:24:37,660
kodiċi għall-kodiċi oġġett, source code għall żero u dawk.

600
00:24:37,660 --> 00:24:40,830
Issa, is-sempliċi fatt li I hit Ħlief dan TextEdit m'għandha l-ebda

601
00:24:40,830 --> 00:24:43,450
effett fuq dawk żero u dawk minħabba I ewwel jeħtieġ li

602
00:24:43,450 --> 00:24:48,260
tell clang ħej, stajt mibdula dawk il-linji ta 'kodiċi, il-

603
00:24:48,260 --> 00:24:49,040
kodiċi tas-sors.

604
00:24:49,040 --> 00:24:51,010
Ikollok bżonn li jirriġeneraw a.out.

605
00:24:51,010 --> 00:24:52,990
Xejn jidher li ġara, iżda fil-kompjuter,

606
00:24:52,990 --> 00:24:55,820
fi linja tal-kmand, biex ngħidu hekk, jiġri xejn meta,

607
00:24:55,820 --> 00:24:57,510
li normalment ifisser kollox huwa tajjeb.

608
00:24:57,510 --> 00:24:59,040
Meta xi ħaġa ma jiġri, dan ifisser

609
00:24:59,040 --> 00:25:00,420
inti messed up, ġeneralment.

610
00:25:00,420 --> 00:25:04,020
>> Mela ejja issa mur a.out, u tabilħaqq issa, għandi "hello,

611
00:25:04,020 --> 00:25:04,440
dinja. "

612
00:25:04,440 --> 00:25:05,990
U issa, xi ngħidu dwar dawn żero u dawk?

613
00:25:05,990 --> 00:25:07,520
Fejn, fil-fatt, huma dawk?

614
00:25:07,520 --> 00:25:10,710
Well, I ma tistax verament biss tip ta 'poke madwar ħafna

615
00:25:10,710 --> 00:25:11,210
b'mod effettiv.

616
00:25:11,210 --> 00:25:12,650
Let me jiftħu TextEdit.

617
00:25:12,650 --> 00:25:14,060
Hawn a.out.

618
00:25:14,060 --> 00:25:17,390
Let me imorru quddiem u tiftaħ dan, u dan huwa dak li apparentement tiegħi

619
00:25:17,390 --> 00:25:19,080
Programm Dehra.

620
00:25:19,080 --> 00:25:21,570
Allura stajt miftuħa, mhux hello.c, iżda a.out.

621
00:25:21,570 --> 00:25:23,960
Iżda dan huwa attwalment mhux dak program tiegħi hija verament.

622
00:25:23,960 --> 00:25:26,450
Ovvjament, dan huwa xi tip ta 'karattri alfabetiċi.

623
00:25:26,450 --> 00:25:28,670
Nara l-ebda żero u dawk, iżda dan huwa

624
00:25:28,670 --> 00:25:30,780
minħabba a.out huwa programm.

625
00:25:30,780 --> 00:25:33,540
Żero u dawk - imma TextEdit, kif tissuġġerixxi l-isem, huwa

626
00:25:33,540 --> 00:25:37,130
bħad notepad fuq Windows, huwa biss editur test, dan huwa

627
00:25:37,130 --> 00:25:39,730
konfużjoni kollha ta 'dawk żerijiet u dawk li

628
00:25:39,730 --> 00:25:41,870
għalkemm dawn kienu, liema?

629
00:25:41,870 --> 00:25:43,380
Karattri ASCII.

630
00:25:43,380 --> 00:25:45,020
>> Allura lura nhar l-Erbgħa, aħna biss ħarāet bil din

631
00:25:45,020 --> 00:25:48,740
immappjar arbitrarja ta 'numri, jew bits, għall-ittri ta' l-

632
00:25:48,740 --> 00:25:51,690
alfabett u simboli punteġġjatura u simili.

633
00:25:51,690 --> 00:25:54,920
Allura TextEdit, li huwa editur test għamlet interpretazzjoni żbaljata

634
00:25:54,920 --> 00:25:57,270
dawk il-mudelli ta 'żero u dawk li huma mistennija li jkunu

635
00:25:57,270 --> 00:25:59,990
istampar kliem, bħal "hello, dinja." Huwa jesponuhom

636
00:25:59,990 --> 00:26:02,150
kif ASCII, u hu għalhekk li jistenna messy ftit.

637
00:26:02,150 --> 00:26:04,910
Issa, hemm xi ħjiel ta 'korrettezza fil hawn.

638
00:26:04,910 --> 00:26:08,090
Avviż jekk I jenfasizzaw, hemm ħjiel ta 'fatt "hello,

639
00:26:08,090 --> 00:26:10,810
dinja, "sabiex x'imkien f'dak il-programm huwa

640
00:26:10,810 --> 00:26:12,120
is-sentenza I kiteb.

641
00:26:12,120 --> 00:26:14,610
Imma ejja imorru quddiem u issa ara ma 'programm differenti.

642
00:26:14,610 --> 00:26:17,420
Din mhix waħda aħna ser tuża din ta 'spiss, iżda wkoll ma

643
00:26:17,420 --> 00:26:19,970
Mac u se jkun ġewwa ta 'l-appliance CS50.

644
00:26:19,970 --> 00:26:23,940
Let me imorru quddiem u tiftaħ ma 'programm imsejjaħ XXD.

645
00:26:23,940 --> 00:26:26,530
>> Lura fil-ġurnata, bosta programmi kienu ssemmew b'mod ġust cryptically,

646
00:26:26,530 --> 00:26:28,200
u għalhekk it-tendenza tkompli.

647
00:26:28,200 --> 00:26:31,160
Iżda-b ifisser bżiq dan il-programm kif binarja.

648
00:26:31,160 --> 00:26:32,330
Ma run.

649
00:26:32,330 --> 00:26:35,770
Uri lili bħala żero u dawk, u dan huwa l-Ċ

650
00:26:35,770 --> 00:26:37,190
program aħna biss kiteb.

651
00:26:37,190 --> 00:26:39,920
Issa, I, bħala bniedem hawn, jien onestament ma jkollu ebda idea dak li

652
00:26:39,920 --> 00:26:42,230
dawn it-tendenzi differenti ta 'żero u dawk jirrappreżentaw.

653
00:26:42,230 --> 00:26:45,320
Lura fil-ġurnata, I, bl punch cards tiegħi jew bħalhom, kieku

654
00:26:45,320 --> 00:26:48,080
attwalment ikollhom ħarsa sa liema dawn it-tendenzi differenti ta '

655
00:26:48,080 --> 00:26:51,560
01111000, attwalment jirrappreżentaw.

656
00:26:51,560 --> 00:26:54,390
Jew agħar, nixtieq bżonn tagħmel l-ippanċjar jew il-ħolqien

657
00:26:54,390 --> 00:26:56,130
ta 'dawn it-tendenzi ta' żero u dawk.

658
00:26:56,130 --> 00:27:00,410
Iżda għal issa, jieħdu fuq il-fidi li CPU, Intel ġewwa, sabiex

659
00:27:00,410 --> 00:27:03,440
biex ngħidu hekk, ġewwa ta 'kollha ta' kompjuters tagħna f'dawn il-jiem, jaf

660
00:27:03,440 --> 00:27:05,100
kif jinterpretaw dawn żero u dawk.

661
00:27:05,100 --> 00:27:07,010
U xi żero u dawk jfissirx istampar.

662
00:27:07,010 --> 00:27:09,040
Xi żero u dawk jfissirx play ħoss.

663
00:27:09,040 --> 00:27:13,630
Xi zeroes u dawk jfissirx jieħdu jintuza mill-utent mill-keyboard.

664
00:27:13,630 --> 00:27:15,960
Hemm kull xorta ta 'mudelli differenti, iżda aħna Thankfully,

665
00:27:15,960 --> 00:27:19,680
bħala bnedmin, biss ġeneralment bżonn ninkwetaw dwar l-ipprogrammar mill-

666
00:27:19,680 --> 00:27:21,270
dan pjuttost ogħla livell.

667
00:27:21,270 --> 00:27:24,320
U fil-klassijiet CS oħra jistgħu ma wieħed jidħol aktar fil-fond l isfel u jfittxu

668
00:27:24,320 --> 00:27:26,820
lejn affarijiet bħall-dawk żero u dawk, jew għadhom

669
00:27:26,820 --> 00:27:28,000
affarijiet oħra għadhom.

670
00:27:28,000 --> 00:27:29,210
>> Allura issa ejja jikkonvertu dan.

671
00:27:29,210 --> 00:27:32,550
Ejja jimxu malajr ħafna bogħod minn C u jimxu lejn xi ħaġa

672
00:27:32,550 --> 00:27:36,390
ftit aktar comforting, ftit aktar eċċitanti, f'dak

673
00:27:36,390 --> 00:27:39,340
nistgħu tikseb lura animazzjonijiet tagħna u ħsejjes u simili li

674
00:27:39,340 --> 00:27:40,940
b'mod ċar ikunu ħarbu magħna f'dan il-

675
00:27:40,940 --> 00:27:42,480
pjuttost primitive interface.

676
00:27:42,480 --> 00:27:46,430
Allura dan il-programm istess Ċ jistgħu jkunu rappreżentati issa f'dan

677
00:27:46,430 --> 00:27:50,060
lingwa ta 'programmar imsejjaħ Scratch kif ġej.

678
00:27:50,060 --> 00:27:54,230
Dan huwa l-ekwivalenti ta 'dan il-programm dinja bonjour miktub

679
00:27:54,230 --> 00:27:57,370
dan puzzle biċċa l-istil tal-lingwa imsejħa Scratch.

680
00:27:57,370 --> 00:28:00,600
So let me go l quddiem u tiftaħ dan il-programm ħafna.

681
00:28:00,600 --> 00:28:01,850
Huwa sejjaħ għal darb'oħra Scratch.

682
00:28:01,850 --> 00:28:03,880
Huwa liberament disponibbli, u din hija l-istess ħaġa aħna

683
00:28:03,880 --> 00:28:05,120
bdiet illum fuq.

684
00:28:05,120 --> 00:28:07,790
>> Allura dan hawnhekk huwa Scratch, u huwa maqsum ftit

685
00:28:07,790 --> 00:28:09,700
biċċiet differenti.

686
00:28:09,700 --> 00:28:12,690
Dwar id-dritt nett, aħna għandna l-istadju hekk imsejħa, u

687
00:28:12,690 --> 00:28:13,670
fil-fatt, li meta l-cookies

688
00:28:13,670 --> 00:28:15,440
mwettqa biss daqsxejn ilu.

689
00:28:15,440 --> 00:28:19,660
U fuq l-istadju huma affarijiet msejħa sprites, karattri, jew

690
00:28:19,660 --> 00:28:21,030
oġġetti, jew entitajiet.

691
00:28:21,030 --> 00:28:23,320
Hija ma verament jimpurtax kif inti taħseb minnhom, imma huma

692
00:28:23,320 --> 00:28:26,740
huma programmabbli, ħwejjeġ mobbli, u f'dan il-każ, dan

693
00:28:26,740 --> 00:28:30,730
programm li student kiteb tagħna għandha koppja ta 'gingerbread

694
00:28:30,730 --> 00:28:32,990
cookies, koppja ta 'cookies ċirkolari, mazz sħiħ ta'

695
00:28:32,990 --> 00:28:35,430
qlub, mazz sħiħ ta 'nuċċalijiet.

696
00:28:38,170 --> 00:28:42,420
Minħabba dan, hu jew hi kapaċi programm kull wieħed minn dawn

697
00:28:42,420 --> 00:28:44,720
karattri individwali separatament.

698
00:28:44,720 --> 00:28:46,480
>> Issa, dak ma jfisser għall-programm dawn il-karattri?

699
00:28:46,480 --> 00:28:49,440
Well, let me imorru quddiem u kklikkja fuq dan cookie naħa tax-xellug

700
00:28:49,440 --> 00:28:51,830
u iscroll fuq ix-xellug ta 'fuq hawn.

701
00:28:51,830 --> 00:28:53,670
Fl-xellug ta 'fuq tal-iskrin tiegħi issa hija l-

702
00:28:53,670 --> 00:28:55,280
hekk imsejħa skripts qasam.

703
00:28:55,280 --> 00:28:58,790
Dan huwa tip ta 'lavanja vojt, inizjalment, fuq liema nista

704
00:28:58,790 --> 00:29:01,540
drag u qatra biċċiet puzzle li, franchement, jagħmlu

705
00:29:01,540 --> 00:29:03,020
eżattament dak li jgħidu.

706
00:29:03,020 --> 00:29:05,820
Fuq nett ta 'dan il-munzell ta' biċċiet puzzle hija l-kelma

707
00:29:05,820 --> 00:29:09,340
Meta Bandiera Ħadra għafast, u jekk inti ma Avviż qabel,

708
00:29:09,340 --> 00:29:12,300
il-mod bdejt li l-kanzunetta cookie kienet tikklikkja, litteralment,

709
00:29:12,300 --> 00:29:13,320
aħdar bandiera.

710
00:29:13,320 --> 00:29:16,590
Allura li l-biċċa puzzle fil quċċata xellug hemm jfisser meta l-

711
00:29:16,590 --> 00:29:19,780
klikks tal-bniedem l-bandiera aħdar, ipproċediet biex tagħmel

712
00:29:19,780 --> 00:29:21,110
l-affarijiet li ġejjin.

713
00:29:21,110 --> 00:29:23,330
>> Issa, dak ma huma cookie tipproċedi biex tagħmel?

714
00:29:23,330 --> 00:29:25,810
I ma verament jafu kif jinterpretaw dan s'issa, iżda l-

715
00:29:25,810 --> 00:29:29,220
cookie apparentement stabbiliti groove tagħha għal żero, allura stennew

716
00:29:29,220 --> 00:29:31,740
tliet sekondi, imbagħad mibdula grupp tagħha għal waħda, allura

717
00:29:31,740 --> 00:29:33,590
stenniet tieni, allura mibdula tagħha

718
00:29:33,590 --> 00:29:35,100
lura groove għal wieħed.

719
00:29:35,100 --> 00:29:37,373
U allura dan fil-fatt qisu daqsxejn ta 'bug, m'għandux

720
00:29:37,373 --> 00:29:39,440
jkollhom jibdlu groove tagħha ġdid u għal darb'oħra sakemm huwa

721
00:29:39,440 --> 00:29:43,380
qed jinbidlu x'imkien ieħor, iżda din is-serje ta 'passi huwa dak

722
00:29:43,380 --> 00:29:46,800
tiddetta l-aġir ta 'dan cookie partikolari.

723
00:29:46,800 --> 00:29:49,180
Mela ejja fil-fatt scroll lura u mhux tħares lejn xi ħaġa

724
00:29:49,180 --> 00:29:50,430
pjuttost tant kumplessa s'issa.

725
00:29:50,430 --> 00:29:52,260
Let me imorru quddiem u mur File, New,

726
00:29:52,260 --> 00:29:53,560
u jiksbu lavanja nadif.

727
00:29:53,560 --> 00:29:56,590
>> Allura issa, I tabilħaqq żona iskrittura vojta, stadju vojta,

728
00:29:56,590 --> 00:29:59,380
bl Scratch tagħna Sprite default, u fuq ix-xellug ta 'fuq

729
00:29:59,380 --> 00:30:01,670
fuq l-iskrin tiegħi għandi l-pallet ta 'kull tal taghhom

730
00:30:01,670 --> 00:30:03,400
biċċiet disponibbli puzzle.

731
00:30:03,400 --> 00:30:06,300
U aħna mhux se jmorru permezz kważi li ħafna minn dawn l-affarijiet

732
00:30:06,300 --> 00:30:09,470
illum għaliex, għal darb'oħra, ħafna minnhom huma ta 'spjegazzjoni, iżda aħna se

733
00:30:09,470 --> 00:30:12,370
jippruvaw jikkategorizzaw lilhom u tfakkar l-similaritajiet

734
00:30:12,370 --> 00:30:15,380
ma 'dawn il-lingwi futuri li aħna se adsa.

735
00:30:15,380 --> 00:30:19,180
U fl quċċata xellug hawnhekk huwa l-ewwel Meta Bandiera Ħadra għafast,

736
00:30:19,180 --> 00:30:22,170
so let me drag dan hawn fuq, zoom out a bit.

737
00:30:22,170 --> 00:30:25,780
U jekk I ikklikkja l-bandiera aħdar, xejn verament jiġri minħabba

738
00:30:25,780 --> 00:30:29,360
I ma mehmuża ebda loġika, kwalunkwe stqarrija biex ngħidu hekk, biex

739
00:30:29,360 --> 00:30:31,040
dik il-bandiera aħdar, so let me go sal-

740
00:30:31,040 --> 00:30:32,500
Kategoriji minn hawn.

741
00:30:32,500 --> 00:30:34,840
Jien bħalissa fil-kategorija ta 'Kontroll.

742
00:30:34,840 --> 00:30:37,630
Jien minflok se jinżlu għall-kategorija Jistenna, u

743
00:30:37,630 --> 00:30:39,970
hemm mazz sħiħ ta 'affarijiet hawn li tgħid Say,

744
00:30:39,970 --> 00:30:43,110
Aħseb, Bidla Costume Kulur Iswiċċ,.

745
00:30:43,110 --> 00:30:44,860
>> Allura inti tista 'tagħmel affarijiet iblah mal-kostumi u

746
00:30:44,860 --> 00:30:45,870
ħsejjes u simili.

747
00:30:45,870 --> 00:30:49,970
Let me imorru quddiem u biss jgħidu Say, u issa avviż kif I drag

748
00:30:49,970 --> 00:30:52,940
u qatra din il-biċċa puzzle, li għaddej biex jridu lukkett

749
00:30:52,940 --> 00:30:55,010
fil-forma korrispondenti.

750
00:30:55,010 --> 00:30:58,020
Allura meta I aqbad u itlaq ġurdien tiegħi, huma lock

751
00:30:58,020 --> 00:31:01,770
flimkien, u issa jekk immur hawn fuq u kklikkja l-bandiera aħdar,

752
00:31:01,770 --> 00:31:05,910
il-qattus ma fil-fatt jgħidu bonjour għaliex dan huwa dak li hu ġewwa

753
00:31:05,910 --> 00:31:06,980
ta 'din il-kaxxa bajda.

754
00:31:06,980 --> 00:31:08,900
Aħna ser malajr tara li din il-kaxxa bajda huwa dak li jissejjaħ

755
00:31:08,900 --> 00:31:10,250
argument, jew parametru.

756
00:31:10,250 --> 00:31:12,560
Huwa mod ta 'jinbidlu l-imġieba ta', f'dan il-każ,

757
00:31:12,560 --> 00:31:15,070
puzzle biċċa, imma jekk irrid ngħid eżattament dak li għidt

758
00:31:15,070 --> 00:31:18,610
qabel, jgħidu bonjour, dinja, I issa tista 'tmur lura fuq hawn,

759
00:31:18,610 --> 00:31:21,990
ikklikkja play, u "hello, dinja" huwa dak qal.

760
00:31:21,990 --> 00:31:24,340
>> Allura aħna litteralment programmazzjoni issa.

761
00:31:24,340 --> 00:31:27,540
Huwa mhux kollha li konvinċenti ta 'programm, iżda mill-inqas

762
00:31:27,540 --> 00:31:30,140
huwa ftit xi ħaġa aktar konvinċenti minn dik jistenna, bi

763
00:31:30,140 --> 00:31:31,300
Ewwel daqqa t'għajn, bħal dan.

764
00:31:31,300 --> 00:31:34,190
U nistgħu malajr ħafna jiksbu l-aktar espressiva

765
00:31:34,190 --> 00:31:36,600
għaliex fil Scratch, bħal fil-lingwi l-oħra, hemm kollha

766
00:31:36,600 --> 00:31:40,010
xorta ta 'dikjarazzjonijiet, mhux biss Say jew stampar xi ħaġa, iżda

767
00:31:40,010 --> 00:31:42,650
inti tista 'tagħmel affarijiet simili ta' stennija, kif aħna biss raw ma '

768
00:31:42,650 --> 00:31:44,240
il-cookie, xi numru ta 'sekonda.

769
00:31:44,240 --> 00:31:46,440
Inti tista 'tilgħab ħsejjes fl-ambjent ta' Scratch biss

770
00:31:46,440 --> 00:31:49,050
bħal inti tista 'fil-ħoss tal-kompjuter normali play programm.

771
00:31:49,050 --> 00:31:52,440
Tista 'tiċċekkja liema huma msejħa espressjonijiet Boolean.

772
00:31:52,440 --> 00:31:55,630
Allura issa, ejja nibdew biex iżżid toolkit tagħna xi terminoloġija

773
00:31:55,630 --> 00:31:58,840
li attwalment tirrigwarda l-eżempju li Joseph u jien ma

774
00:31:58,840 --> 00:32:00,080
hawn mal-kalzetti.

775
00:32:00,080 --> 00:32:03,040
Allura dikjarazzjonijiet huma biss dikjarazzjonijiet ta 'fatt.

776
00:32:03,040 --> 00:32:04,160
Agħmel dan.

777
00:32:04,160 --> 00:32:07,370
A direttiva għall-Sprite, jew me-bniedem, li jagħmel xi ħaġa.

778
00:32:07,370 --> 00:32:10,420
A espressjoni Boolean hija xi ħaġa li għandha valur, ta '

779
00:32:10,420 --> 00:32:14,580
hekk imsejħa verità valur, li jew żero jew wieħed, falza jew

780
00:32:14,580 --> 00:32:17,890
vera, off jew fuq, l-ebda jew iva.

781
00:32:17,890 --> 00:32:19,730
Ma verament kwistjoni kif inti taħseb ta 'dan, imma hija

782
00:32:19,730 --> 00:32:20,700
istat binarja.

783
00:32:20,700 --> 00:32:22,610
Kif Nate diskuss fil-video l-Erbgħa, 2

784
00:32:22,610 --> 00:32:23,570
affarijiet differenti.

785
00:32:23,570 --> 00:32:25,740
>> Għalhekk fl Scratch, espressjonijiet Boolean jiġri li tħares

786
00:32:25,740 --> 00:32:28,910
bħal dawn l-oġġetti blu hawn, u f'dan il-każ, il-kwistjoni

787
00:32:28,910 --> 00:32:30,960
marka jimplika li int tistaqsi mistoqsija.

788
00:32:30,960 --> 00:32:34,250
Huwa l-qattus, jew il-Sprite, li jmissu l-mouse pointer?

789
00:32:34,250 --> 00:32:36,580
Allura dan huwa biss eżempju wieħed ta 'blokka scratch li għaddej

790
00:32:36,580 --> 00:32:39,950
biex inessu biex jiċċekkjaw iva jew le, huwa l-ġurdien jmissu l-

791
00:32:39,950 --> 00:32:40,790
Sprite fuq l-iskrin?

792
00:32:40,790 --> 00:32:42,840
U dan jista 'jkun utli jekk inti fil-fatt tixtieq li tagħmel affarijiet

793
00:32:42,840 --> 00:32:43,820
bil-maws.

794
00:32:43,820 --> 00:32:46,470
Minbarra l-espressjonijiet Boolean, aħna għandna l-affarijiet

795
00:32:46,470 --> 00:32:49,110
bħall huwa l-maws 'l isfel, sabiex inti tista' tiskopri dak it-tip ta '

796
00:32:49,110 --> 00:32:50,200
kwistjoni kif ukoll.

797
00:32:50,200 --> 00:32:52,590
Nistgħu nagħmlu l-matematika jekk inti fil-fatt tixtieq, u hemm

798
00:32:52,590 --> 00:32:55,170
użi attwalment aktar konvinċenti għal dan milli sempliċiment pur ta '

799
00:32:55,170 --> 00:32:56,400
aritmetika, kif Ser naraw.

800
00:32:56,400 --> 00:32:59,690
Randomness Psewdo u jagħmlu program tiegħek jidhru li jaħsbu

801
00:32:59,690 --> 00:33:03,490
jew jġib ruħu differenti bbażata fuq xi valuri apparentement każwali,

802
00:33:03,490 --> 00:33:06,610
u allura għandna affarijiet simili espressjonijiet Boolean simili U.

803
00:33:06,610 --> 00:33:08,830
Mela jekk inti fil-fatt tixtieq li jiċċekkjaw żewġ valuri, Ser naraw fil

804
00:33:08,830 --> 00:33:11,110
Scratch li nistgħu attwalment test jekk dan huwa

805
00:33:11,110 --> 00:33:13,190
vera u dan huwa veru.

806
00:33:13,190 --> 00:33:15,300
Per eżempju, fil-każ ta 'kalzetti tiegħi, I jistgħu stajt fil-

807
00:33:15,300 --> 00:33:19,045
ħafna aħħar staqsa l-mistoqsija jekk suletta tax-xellug huwa fuq u tal-lemin suletta

808
00:33:19,045 --> 00:33:20,610
huwa fuq, nieqaf.

809
00:33:20,610 --> 00:33:22,710
Inti kollha magħmula għall-ġurnata, sabiex ikun

810
00:33:22,710 --> 00:33:24,300
opportunità għal dan.

811
00:33:24,300 --> 00:33:27,740
>> Mela ejja imorru quddiem u jippruvaw biċċa xi wħud minn dawn flimkien

812
00:33:27,740 --> 00:33:31,570
u jmorru fi ftit eżempji iktar

813
00:33:31,570 --> 00:33:32,610
konvinċenti minn dan wieħed.

814
00:33:32,610 --> 00:33:35,770
So let me aqbad hawn u jiftħu xi wħud mill-eżempji

815
00:33:35,770 --> 00:33:38,350
li dejjem se jkun fuq il-websajt tal-kors kif ukoll, u

816
00:33:38,350 --> 00:33:39,870
jiftħu hello2.

817
00:33:39,870 --> 00:33:42,910
Għalhekk fl hello2 hawn, għandna programm li qed jagħmel ftit

818
00:33:42,910 --> 00:33:46,290
affarijiet, imma hija ma nagħmilx hekk b'mod effettiv kif nistgħu.

819
00:33:46,290 --> 00:33:48,900
Allura hawnhekk jgħid "hello, dinja" għat-tieni waħda u mbagħad tistenna

820
00:33:48,900 --> 00:33:49,450
għat-tieni.

821
00:33:49,450 --> 00:33:51,720
U mbagħad ma darb'oħra, u mbagħad ma darb'oħra.

822
00:33:51,720 --> 00:33:55,530
Mela jekk jien ikklikkja l-bandiera aħdar, Scratch jgħid "Hello, dinja.

823
00:33:55,530 --> 00:33:57,160
Hello. Dinja,

824
00:33:57,160 --> 00:34:00,080
Hello, dinja. "U dan huwa ovvjament kandidat issa għal

825
00:34:00,080 --> 00:34:00,860
titjib.

826
00:34:00,860 --> 00:34:03,070
>> X'hemm-titjib marġinali, wieħed jittama, nistgħu

827
00:34:03,070 --> 00:34:07,610
issa tagħmel jekk Scratch jappoġġja l-kunċett?

828
00:34:07,610 --> 00:34:08,310
Xi tip ta 'linja.

829
00:34:08,310 --> 00:34:10,960
Xi tip ta 'ripetizzjoni, issa, ikun sbieħ, so let me

830
00:34:10,960 --> 00:34:11,920
fil-fatt jipprovaw dan.

831
00:34:11,920 --> 00:34:13,870
Let me fil-fatt imorru u jimxu dan.

832
00:34:13,870 --> 00:34:16,449
Allura avviż jista 'jinqata blokki faċilment daqs inti tista' żżid l-

833
00:34:16,449 --> 00:34:17,420
jehmiżhom.

834
00:34:17,420 --> 00:34:20,730
Let me go taħt Kontroll, iscroll stabbiliti hawn, u fil-fatt,

835
00:34:20,730 --> 00:34:24,000
hemm din il-biċċa puzzle hawn, Irrepeti u Forever u

836
00:34:24,000 --> 00:34:24,870
Forever Jekk.

837
00:34:24,870 --> 00:34:28,500
Allura hemm numru ta 'modi li jesprimu constructs looping

838
00:34:28,500 --> 00:34:29,340
fil Scratch.

839
00:34:29,340 --> 00:34:31,730
Il-wieħed I probabilment tixtieq hawnhekk mhix Forever minħabba I biss

840
00:34:31,730 --> 00:34:34,639
tridx dan iseħħ tliet darbiet, iżda probabbilment Irrepeti.

841
00:34:34,639 --> 00:34:38,449
So let me jkaxkru Irrepeti hawn fuq, drag u qatra, u

842
00:34:38,449 --> 00:34:42,530
issa minflok qal "bonjour, dinja" tliet darbiet separati,

843
00:34:42,530 --> 00:34:44,230
let me drag din il-biċċa puzzle fil hawn.

844
00:34:44,230 --> 00:34:46,610
U anki jekk ma jidhirx li jitwaħħal, il-programm huwa intelliġenti

845
00:34:46,610 --> 00:34:48,920
biżżejjed biex tirrealizza dan se jikbru biex timla, dan huwa l-

846
00:34:48,920 --> 00:34:51,270
forom dik il-kwistjoni, u mhux id-daqs assolut.

847
00:34:51,270 --> 00:34:54,030
Let me jibdlu l-ripetizzjoni għal tlieta, u issa let me go

848
00:34:54,030 --> 00:34:56,560
quddiem u drag Stenna Wieħed Tieni fil hemm ukoll.

849
00:34:56,560 --> 00:34:59,220
Huwa ser snap fil ukoll, u hekk issa jien ser jkaxkru

850
00:34:59,220 --> 00:35:01,370
dawn guys minn hawn u ftit tarmihom minħabba I

851
00:35:01,370 --> 00:35:02,710
ma jeħtiġuhom aktar.

852
00:35:02,710 --> 00:35:05,920
Let me zoom out u kklikkja l-bandiera aħdar issa, u aħna għandna

853
00:35:05,920 --> 00:35:09,600
l-istess programm, iżda, kif I mbassra qabel, aħjar

854
00:35:09,600 --> 00:35:12,200
mfassla għaliex inti tista 'jimmaġina kif bad dan il-programm

855
00:35:12,200 --> 00:35:14,410
se tikseb, ċertament estetikament, jekk kellek biex

856
00:35:14,410 --> 00:35:16,640
tibda l-ikkupjar u pasta, ikkupjar u pasta, jew

857
00:35:16,640 --> 00:35:20,020
jittrattienu u twaqqa l-affarijiet darn istess ġdid u għal darb'oħra.

858
00:35:20,020 --> 00:35:22,260
>> Issa, sempliċiment tgħid għalf fuq l-iskrin, l-istampar għall-

859
00:35:22,260 --> 00:35:25,350
iskrin, verament kollha mhux li eċċitanti, so ejja tiftaħ

860
00:35:25,350 --> 00:35:26,580
varjanza 3 hawn.

861
00:35:26,580 --> 00:35:29,810
U issa, kif tkun taf tara, dan ser malajr jiksbu annoying -

862
00:35:29,810 --> 00:35:30,850
[Meow]

863
00:35:30,850 --> 00:35:31,940
DAVID Malan: - imma hija wkoll tip ta 'ħelu.

864
00:35:31,940 --> 00:35:35,244
[Meow]

865
00:35:35,244 --> 00:35:37,460
DAVID Malan: Okay, hekk aħjar, u nistgħu ċertament jużaw dik

866
00:35:37,460 --> 00:35:41,060
transizzjoni istess Tkissir fi bċejjeċ dan up fis looping

867
00:35:41,060 --> 00:35:43,520
istruttura, imma ejja jagħmluha aktar interessanti xorta.

868
00:35:43,520 --> 00:35:47,480
>> Let me imorru quddiem u tiftaħ varjanza 4 hawn, fejn I

869
00:35:47,480 --> 00:35:50,020
jieħdu l-affarijiet pass ulterjuri.

870
00:35:50,020 --> 00:35:54,450
Allura skond dan, għalkemm dan huwa iblah fl-ewwel

871
00:35:54,450 --> 00:35:58,530
t'għajn, dak li huwa dan il-programm se jagħmlu?

872
00:35:58,530 --> 00:35:59,790
Huwa ser meow darba.

873
00:35:59,790 --> 00:36:00,160
Għaliex?

874
00:36:00,160 --> 00:36:03,340
Ukoll, wieħed huwa, safejn naf, dejjem inqas minn tnejn.

875
00:36:03,340 --> 00:36:04,890
M'hemm l-ebda kunċett ta 'randomness hawn.

876
00:36:04,890 --> 00:36:07,240
Stajt litteralment hard-kodifikati wieħed u tnejn, imma din hija

877
00:36:07,240 --> 00:36:10,370
Eżempju issa li attwalment jużaw espressjoni Boolean.

878
00:36:10,370 --> 00:36:13,650
Ħafna bħal kif Joseph għamlet fil pseudocode tiegħu, l-indentazzjoni IF

879
00:36:13,650 --> 00:36:17,170
issib kalzetti tqabbil imbagħad tagħmel dan li ġej, hawnhekk għandna

880
00:36:17,170 --> 00:36:19,750
espressjoni IF waħda hija anqas minn 2 Imbagħad -

881
00:36:19,750 --> 00:36:21,820
u fil-fatt aħna anke jkollhom xi ftit ta 'indentazzjoni,

882
00:36:21,820 --> 00:36:24,480
fejn il-vjola huwa kemmxejn indentati lejn il-lemin -

883
00:36:24,480 --> 00:36:26,600
Imbagħad int ser jilagħbu l-meow ħoss.

884
00:36:26,600 --> 00:36:30,060
Issa, f'dan il-każ, li wieħed huwa dejjem anqas minn tnejn, għalhekk dan

885
00:36:30,060 --> 00:36:31,970
huwa tip ta 'skart ta' kundizzjoni.

886
00:36:31,970 --> 00:36:34,890
Iżda aħna ser tkun tista, kif aħna ser tara, li plug affarijiet oħra fis

887
00:36:34,890 --> 00:36:37,420
dawn placeholders fejn wieħed u tnejn issa huma.

888
00:36:37,420 --> 00:36:41,340
Mela ejja issa javvanzaw għal eżempju 5 ta 'dawn bosta

889
00:36:41,340 --> 00:36:45,850
hellos u ħarsa lejn dak li dan il-programm għaddej biex tagħmel.

890
00:36:45,850 --> 00:36:48,710
>> Allura issa, f'sentenza Ingliż, kif ma dan

891
00:36:48,710 --> 00:36:51,460
Programm jaġixxu?

892
00:36:51,460 --> 00:36:52,950
UDJENZA: Meows nofs il-ħin.

893
00:36:52,950 --> 00:36:55,380
DAVID Malan: nofs Meow tal-ħin, għalhekk dan huwa mod ta '

894
00:36:55,380 --> 00:36:56,700
jwasslu idea sempliċi ħafna.

895
00:36:56,700 --> 00:36:59,400
Anki jekk aħna jiġri li tkun qed tuża xi inugwaljanzi hawn

896
00:36:59,400 --> 00:37:01,860
f'xi numri, dan huwa verament ftit programmatical

897
00:37:01,860 --> 00:37:09,490
mod, mod preċiż, ta 'tgħid jekk il-munita jitla irjus, mur

898
00:37:09,490 --> 00:37:10,270
quddiem u meow.

899
00:37:10,270 --> 00:37:13,540
Jew bil-maqlub, jekk il-munita jitla 'dnub, ma meow.

900
00:37:13,540 --> 00:37:15,110
U f'dan il-każ, kif nistgħu jesprimu dak?

901
00:37:15,110 --> 00:37:17,950
Aħna ser pick numru każwali minn 1 sa 10, u jekk dik

902
00:37:17,950 --> 00:37:21,110
in-numru huwa inqas minn 6, imorru quddiem u meow.

903
00:37:21,110 --> 00:37:22,260
U kif ma din tikseb fil hawn?

904
00:37:22,260 --> 00:37:24,620
Ukoll għal darb'oħra, l-avviż biss il-jittrattienu u twaqqa u

905
00:37:24,620 --> 00:37:26,190
affarijiet lukketti fil-post.

906
00:37:26,190 --> 00:37:28,020
>> Allura issa ejja ara jekk dan randomness xogħlijiet.

907
00:37:28,020 --> 00:37:29,845
Let me imorru quddiem u kklikkja l-bandiera aħdar.

908
00:37:29,845 --> 00:37:31,120
[Meow]

909
00:37:31,120 --> 00:37:32,000
DAVID Malan: Okay.

910
00:37:32,000 --> 00:37:33,430
[Meow]

911
00:37:33,430 --> 00:37:35,260
DAVID Malan: Okay.

912
00:37:35,260 --> 00:37:38,510
Okay, tajba, hekk aħna ltqajna kapijiet, irjus, dnub effettiv.

913
00:37:38,510 --> 00:37:39,295
Dnub.

914
00:37:39,295 --> 00:37:39,590
[Meow]

915
00:37:39,590 --> 00:37:41,829
DAVID Malan: Kapijiet.

916
00:37:41,829 --> 00:37:43,220
[Meow]

917
00:37:43,220 --> 00:37:44,040
DAVID Malan:. Eċċellenti

918
00:37:44,040 --> 00:37:46,220
Huwa dejjem skomdi meta biss statistikament ikollok bad

919
00:37:46,220 --> 00:37:48,510
run, u huwa l-irjus, u l-programm fil-fatt ma

920
00:37:48,510 --> 00:37:49,230
xogħol bħala youd tama.

921
00:37:49,230 --> 00:37:51,210
Iżda dan iż-żmien, hija maħduma, u aħna jidhru li jkollhom, jekk aħna ma

922
00:37:51,210 --> 00:37:53,830
dan in-numru ta infinit ta 'drabi, odds 50%.

923
00:37:53,830 --> 00:37:56,950
Issa mill-ġdid, mhux kollha li interessanti, biss tagħmel qtates

924
00:37:56,950 --> 00:37:59,840
meow, so ejja ara jekk aħna ma tista 'quddiem din id-daqsxejn aktar

925
00:37:59,840 --> 00:38:01,820
hawn fil-verżjoni 6.

926
00:38:01,820 --> 00:38:05,620
Allura issa, aħna għandna verżjoni verament annoying -

927
00:38:05,620 --> 00:38:08,215
[MEOWS kull ftit sekondi]

928
00:38:08,215 --> 00:38:10,640
DAVID Malan: - u dan huwa dak magħruf, ġenerali, bħala

929
00:38:10,640 --> 00:38:11,670
infinita loop.

930
00:38:11,670 --> 00:38:14,190
>> Loop infinita Allura f'dan il-każ iħoss ħżiena.

931
00:38:14,190 --> 00:38:16,970
Huwa definittivament se tibda ħoss ħażina, u għadhom infinita

932
00:38:16,970 --> 00:38:18,740
loops mhumiex dejjem ħżiena.

933
00:38:18,740 --> 00:38:20,910
Tista 'taħseb ta kuntest programmi tal-kompjuter fejn youd

934
00:38:20,910 --> 00:38:22,910
fil-fatt tixtieq li loop infinita?

935
00:38:22,910 --> 00:38:23,691
Yeah?

936
00:38:23,691 --> 00:38:26,520
UDJENZA: Meta inti tixtieq li jiċċekkjaw kundizzjoni.

937
00:38:26,520 --> 00:38:28,240
DAVID Malan: Okay, meta inti tixtieq li żżomm kontroll kundizzjoni?

938
00:38:28,240 --> 00:38:29,190
Bħal dak?

939
00:38:29,190 --> 00:38:30,440
UDJENZA: [inaudible]

940
00:38:36,060 --> 00:38:38,170
DAVID Malan: Okay, tajba, hekk jekk kellek xi programm, xi

941
00:38:38,170 --> 00:38:40,440
tip ta 'ħaġa awtomazzjoni dar, fejn inti tixtieq li kontinwament

942
00:38:40,440 --> 00:38:41,980
monitor huwa xi ħaġa tal-każ.

943
00:38:41,980 --> 00:38:42,850
Huma l-dwal fuq?

944
00:38:42,850 --> 00:38:45,020
Huma l-dwal fuq għaliex forsi għandek timer, u

945
00:38:45,020 --> 00:38:47,360
inti tixtieq li tmur off, jista 'jkollok bżonn tagħmel xi ħaġa

946
00:38:47,360 --> 00:38:48,290
ġdid u għal darb'oħra.

947
00:38:48,290 --> 00:38:50,540
U fil-fatt, taħdit ta 'tajmers, kwalunkwe inti li

948
00:38:50,540 --> 00:38:53,100
arloġġi fuq il-kompjuter tiegħek jew arloġġi diġitali, li l-

949
00:38:53,100 --> 00:38:54,210
infinita loop.

950
00:38:54,210 --> 00:38:56,980
Hija tkompli taġġorna l-ħin għaliex dan huwa kontinwament

951
00:38:56,980 --> 00:38:59,750
verifika u l-iċċekkjar u l-kontroll għandu l-ħin inbidel,

952
00:38:59,750 --> 00:39:01,000
u jekk iva, oh, god tiegħi.

953
00:39:03,670 --> 00:39:04,740
L-arloġġ s finalment mibdula.

954
00:39:04,740 --> 00:39:07,020
Jeħtieġ juri li valur lilek.

955
00:39:07,020 --> 00:39:10,880
Allura billi ħafna mill-linji infinita ta 'żmien huma żball,

956
00:39:10,880 --> 00:39:13,950
jew għall-inqas għal deċiżjoni disinn fqir, xi kultant dawn ma

957
00:39:13,950 --> 00:39:14,785
jkollhom valur tagħhom.

958
00:39:14,785 --> 00:39:18,170
>> Ukoll, ejja avvanz ulterjuri hawn biex hello7.

959
00:39:18,170 --> 00:39:20,410
Allura issa l-programm se tikseb ftit aktar interattiv.

960
00:39:20,410 --> 00:39:23,120
Let me zoom fil hawn, u għal darb'oħra, dan huwa dak sbieħ

961
00:39:23,120 --> 00:39:23,640
dwar Scratch.

962
00:39:23,640 --> 00:39:26,760
U aħna ser tagħmel użu minnha biex tkun ċara, Scratch, biss illum u fil-

963
00:39:26,760 --> 00:39:27,780
problema ġimgħa d-dieħla stabbiliti.

964
00:39:27,780 --> 00:39:31,920
Iżda nhar it-Tnejn, aħna adsa fis C. F'dan il-programm hawn, dan huwa minnu,

965
00:39:31,920 --> 00:39:33,190
dejjem, dan li ġej.

966
00:39:33,190 --> 00:39:35,890
JEKK tmiss il-mouse pointer - issa, li hija l-

967
00:39:35,890 --> 00:39:36,420
kuntest hawn?

968
00:39:36,420 --> 00:39:39,670
Ukoll, u avviż li min s magħżul stabbiliti hawn fuq qiegħ

969
00:39:39,670 --> 00:39:43,060
dritt huwa l-qattus, Sprite waħda, sabiex dawn skripts, dan

970
00:39:43,060 --> 00:39:45,720
programm, japplika għalih speċifikament.

971
00:39:45,720 --> 00:39:48,950
Mela jekk li l-qattus huwa jmissu l-mouse pointer, allura huwa għaddej

972
00:39:48,950 --> 00:39:51,350
jilagħbu din il-isfel u stenna żewġ sekondi, u

973
00:39:51,350 --> 00:39:53,030
imbagħad irrepeti nauseum ad.

974
00:39:53,030 --> 00:39:55,360
>> Mela ejja imorru quddiem u hit play.

975
00:39:55,360 --> 00:39:57,580
Xejn jiġri, imma jekk irrid domestiċi tal-

976
00:39:57,580 --> 00:39:59,310
qattus issa, nista 'sempliċiment.

977
00:39:59,310 --> 00:40:01,130
[Meow]

978
00:40:01,130 --> 00:40:02,244
DAVID Malan: Adorable.

979
00:40:02,244 --> 00:40:05,956
[Meow]

980
00:40:05,956 --> 00:40:08,750
DAVID Malan: Okay, inqas annoying, iżda wkoll gets matt,

981
00:40:08,750 --> 00:40:11,480
hekk ejja jimxu fuq u ara jekk ma nkunux nistgħu tinjetta

982
00:40:11,480 --> 00:40:12,460
loġika ftit aktar.

983
00:40:12,460 --> 00:40:14,300
Dan kien eżempju 7.

984
00:40:14,300 --> 00:40:16,090
>> Hawn fl-eżempju 8, aħna qed tmur biex

985
00:40:16,090 --> 00:40:18,670
jintroduċi kundizzjoni IKTAR.

986
00:40:18,670 --> 00:40:21,440
Allura ħafna bħal furketta litterali fit-triq, fejn inti tista 'tmur

987
00:40:21,440 --> 00:40:24,260
xellug jew inti tista 'tmur dritt, kundizzjoni ta' programmazzjoni

988
00:40:24,260 --> 00:40:28,120
lingwa bħal Scratch, jew kif aħna ser tara C, jistgħu jippermettu li inti

989
00:40:28,120 --> 00:40:32,230
jmorru f'direzzjoni waħda jew oħra permezz ta 'IF IKTAR jinbena.

990
00:40:32,230 --> 00:40:35,160
Allura pjuttost litteralment, JEKK jmissu mouse pointer, dan

991
00:40:35,160 --> 00:40:38,680
se tilgħab xi ħoss, IKTAR li għaddej biex jilagħbu din il ieħor

992
00:40:38,680 --> 00:40:39,800
, ħoss meow.

993
00:40:39,800 --> 00:40:42,510
Issa, jekk inti tista 'tiddeduċi mill-isem ta' dawn il-ħsejjes, inti tista '

994
00:40:42,510 --> 00:40:45,310
probabbilment raden dak dan il-programm kien ifisser li jevokaw

995
00:40:45,310 --> 00:40:46,250
l-idea ta '.

996
00:40:46,250 --> 00:40:48,742
Dan qattus huwa meowing heureusement.

997
00:40:48,742 --> 00:40:49,230
[Meow]

998
00:40:49,230 --> 00:40:51,410
DAVID Malan: B'xorti tajba, iżda ma

999
00:40:51,410 --> 00:40:52,926
pjuttost simili li tintmess.

1000
00:40:52,926 --> 00:40:54,550
[Roars]

1001
00:40:54,550 --> 00:40:57,500
DAVID Malan: Allura issa għandna qattus li se Yell fi inti.

1002
00:40:57,500 --> 00:41:00,570
>> Kull dritt, ukoll, eżempju wieħed aħħar ma 'qtates hawn, u

1003
00:41:00,570 --> 00:41:02,920
ejja verżjoni miftuħa 9 ta 'dan hawn.

1004
00:41:02,920 --> 00:41:06,190
Allura issa, aħna għandna l-ħoss jmiss l-aktar tedjanti li stajt

1005
00:41:06,190 --> 00:41:11,630
isibu, hekk aħna walrus jew iljun baħar hawn li għaddej biex

1006
00:41:11,630 --> 00:41:13,222
tagħmel dan li ġej.

1007
00:41:13,222 --> 00:41:20,870
[QOXRA SIĠILL]

1008
00:41:20,870 --> 00:41:23,310
DAVID Malan: Okay, għalhekk dan se jmorru fuq sakemm inti figura kif

1009
00:41:23,310 --> 00:41:24,640
dan il-programm tax-xogħlijiet.

1010
00:41:24,640 --> 00:41:28,560
Allura dan iż-żmien, dan l-annimal għandha żewġ skripts, u x'hemm

1011
00:41:28,560 --> 00:41:31,050
interessanti hawnhekk huwa li dawn skripts huma ser tesegwixxi

1012
00:41:31,050 --> 00:41:32,260
b'mod parallel.

1013
00:41:32,260 --> 00:41:35,340
Allura għaliex it-tnejn jibdew ma 'waħda bandiera aħdar għafast,

1014
00:41:35,340 --> 00:41:38,080
huwa simili tmur bħal dan, u ż-żewġ programmi jibdew ġestjoni tiegħu

1015
00:41:38,080 --> 00:41:41,370
ladarba anki jekk dawn qed looping għal dejjem.

1016
00:41:41,370 --> 00:41:44,420
Għalhekk fl-iskrittura fuq, għandi xi loġika.

1017
00:41:44,420 --> 00:41:49,275
Xi karatteristiċi ma li tipprovdi up hemm?

1018
00:41:49,275 --> 00:41:50,740
[QOXRA SIĠILL]

1019
00:41:50,740 --> 00:41:51,670
UDJENZA: [inaudible]

1020
00:41:51,670 --> 00:41:53,295
DAVID Malan: Jekk huwa dak?

1021
00:41:53,295 --> 00:41:53,760
[QOXRA SIĠILL]

1022
00:41:53,760 --> 00:41:55,852
UDJENZA: Jekk siekta għal żero, li għaddej biex tibqa 'taqdi l-

1023
00:41:55,852 --> 00:41:58,410
ħoss. [QOXRA SIĠILL]

1024
00:41:58,410 --> 00:41:58,940
DAVID Malan: Okay, tajba.

1025
00:41:58,940 --> 00:42:01,960
Allura IF siekta, tkun xi tkun din hija, dan il-ħaġa oranġjo huwa żero,

1026
00:42:01,960 --> 00:42:05,370
Imbagħad jilagħbu l-ħoss iljun baħar u think "Oh,

1027
00:42:05,370 --> 00:42:06,770
hi, "għal żewġ sekondi.

1028
00:42:06,770 --> 00:42:09,380
Issa, jien ma nafx x'inhu siekta, imma żero iqajjem il-

1029
00:42:09,380 --> 00:42:11,230
idea ta falza jew off.

1030
00:42:11,230 --> 00:42:14,490
Mela jekk huwa siekta falza, hekk jekk le siekta,

1031
00:42:14,490 --> 00:42:15,660
tibqa 'taqdi l-ħoss.

1032
00:42:15,660 --> 00:42:17,350
Kull dritt, ukoll, kif nistgħu jiskonnettjaw din il-ħaġa?

1033
00:42:17,350 --> 00:42:19,310
>> Well, ejja nħarsu lejn l-iskrittura 2 stabbiliti hemmhekk.

1034
00:42:19,310 --> 00:42:22,130
L-iskript 2 jgħid stabbiliti siekta għal żero.

1035
00:42:22,130 --> 00:42:25,180
Avviż huwa wkoll oranġjo, iva, liema Scratch ma hu huwa kuluri

1036
00:42:25,180 --> 00:42:27,400
blokki fil-dell istess jekk tip huwa

1037
00:42:27,400 --> 00:42:28,850
ta loġikament marbuta.

1038
00:42:28,850 --> 00:42:32,850
Hekk biss bħala top up siekta kien oranġjo, u għalhekk hija siekta stabbiliti hawn

1039
00:42:32,850 --> 00:42:34,060
imsemmi fil-blokk oranġjo.

1040
00:42:34,060 --> 00:42:36,170
Iżda dan huwa assenjazzjonijiet varjabbli, hekk bħal fil

1041
00:42:36,170 --> 00:42:39,170
alġebra, inti għandek xuy u z, fil-programmazzjoni għandek

1042
00:42:39,170 --> 00:42:41,440
varjabbli, iżda dawn qed ġeneralment -

1043
00:42:41,440 --> 00:42:42,580
nieqaf ejja għal mument u figura kif

1044
00:42:42,580 --> 00:42:44,280
li twaqqaf dan Barking.

1045
00:42:44,280 --> 00:42:45,480
Kif nista 'nagħmlu dan?

1046
00:42:45,480 --> 00:42:46,480
[QOXRA SIĠILL]

1047
00:42:46,480 --> 00:42:47,920
DAVID Malan: Okay.

1048
00:42:47,920 --> 00:42:49,490
Hija waqfet. Okay.

1049
00:42:49,490 --> 00:42:52,230
>> Hekk biss kif fl-alġebra ikollok varjabbli x, y, uz, iżda fl-

1050
00:42:52,230 --> 00:42:55,260
programmazzjoni, wara varjabbli bħall x, y, uz hija ġeneralment

1051
00:42:55,260 --> 00:42:57,330
frowned fuq għaliex qed mhuwiex f'kull espressiva.

1052
00:42:57,330 --> 00:43:00,070
Huma jkollhom l-ebda tifsira semantika tkun xi tkun, hekk f'ħafna

1053
00:43:00,070 --> 00:43:02,110
ipprogrammar ta 'lingwi, fatturi varjabbli jista' jkollhom sħiħa

1054
00:43:02,110 --> 00:43:05,270
ismijiet sħaħ jew kliem jew frażijiet, bħal siekta, jiġifieri

1055
00:43:05,270 --> 00:43:06,030
dak li jagħmlu.

1056
00:43:06,030 --> 00:43:09,380
Allura din l-iskrittura tieni wkoll kien smigħ għal dejjem, u qal

1057
00:43:09,380 --> 00:43:12,100
jekk iċ-ċavetta, l-Ispazju ewlenin keyboard, huwa

1058
00:43:12,100 --> 00:43:13,370
ippressat, kwistjoni mark.

1059
00:43:13,370 --> 00:43:16,300
Allura hemm kundizzjoni ma 'espressjoni Boolean li l-

1060
00:43:16,300 --> 00:43:19,010
jmorru biex titwieġeb xi mistoqsija jew bil-verità jew falza,

1061
00:43:19,010 --> 00:43:22,880
imbagħad għandi ġewwa ta 'dan IF-ċavetta ispazju hija ppressata U

1062
00:43:22,880 --> 00:43:28,020
IF huwa siekta żero, sett siekta għal wieħed, IKTAR stabbiliti siekta għal żero.

1063
00:43:28,020 --> 00:43:30,510
Allura dan furketta oħra fit-triq, u avviż kif stajt

1064
00:43:30,510 --> 00:43:33,500
nested-tnejn IF kundizzjonijiet, huwa mod ta 'kkontrollar huwa l-

1065
00:43:33,500 --> 00:43:36,610
Bar Ispazju ippressat għaliex jekk iva, jien la jridu jmorru din

1066
00:43:36,610 --> 00:43:38,000
mod jew b'dak il-mod.

1067
00:43:38,000 --> 00:43:40,210
U kif nista aqleb il-valur tal-siekta?

1068
00:43:40,210 --> 00:43:41,410
I għandhom jiċċekkjaw huwa żero?

1069
00:43:41,410 --> 00:43:45,890
Jekk iva, jagħmilha waħda, inkella jagħmel żero sa għalhekk toggle

1070
00:43:45,890 --> 00:43:47,670
żewġ stati tagħha.

1071
00:43:47,670 --> 00:43:50,030
>> Kull dritt, hekk aħna mbagħad xi wħud minn dawn fundamentali

1072
00:43:50,030 --> 00:43:50,540
constructs.

1073
00:43:50,540 --> 00:43:52,810
Aħna espressjonijiet Boolean, u tirrealizza, wisq, dawn huma

1074
00:43:52,810 --> 00:43:54,050
mhux kollha li familjari.

1075
00:43:54,050 --> 00:43:56,730
Fil-fatt, hawn screenshot malajr ta 'kors Harvard CS50

1076
00:43:56,730 --> 00:43:59,740
għodda shopping, u kwalunkwe websajt hemmhekk li tkun checkboxes

1077
00:43:59,740 --> 00:44:02,420
u downs qatra jkollhom verament, dan il-ħin, kienu jużaw

1078
00:44:02,420 --> 00:44:03,430
Espressjonijiet Boolean.

1079
00:44:03,430 --> 00:44:05,760
F'dan il-każ hawnhekk, jekk tikklikkja l-Checkbox li jmiss

1080
00:44:05,760 --> 00:44:08,620
ikbar minn jew ugwali għal 4.5, jew dak li jmiss istess kors

1081
00:44:08,620 --> 00:44:11,200
fakultà, int tispeċifika espressjoni Boolean.

1082
00:44:11,200 --> 00:44:14,780
Urini korsijiet li għalihom dik l-espressjoni hija vera.

1083
00:44:14,780 --> 00:44:17,080
Jew il-lemin, ma tmurx kontra korsijiet jien

1084
00:44:17,080 --> 00:44:20,440
teħid, jekk dan hija kontrollata, allura iva, inti tixtieq li tivverifika

1085
00:44:20,440 --> 00:44:22,890
din il-kundizzjoni, inkella inti tixtieq li jinjoraha.

1086
00:44:22,890 --> 00:44:25,170
Espressjonijiet Allura Boolean huma tip ta 'kollha madwar, iżda meta

1087
00:44:25,170 --> 00:44:28,080
aħna tpoġġihom fil-kondizzjonijiet, jekk IF kundizzjonijiet, IF

1088
00:44:28,080 --> 00:44:30,480
Elses, jew nistgħu saħansitra aktar fil-fond jissimulaw

1089
00:44:30,480 --> 00:44:32,830
livelli, JEKK IKTAR JEKK IKTAR -

1090
00:44:32,830 --> 00:44:34,430
b'tali mod li tip ta 'stat tenarji.

1091
00:44:34,430 --> 00:44:36,920
Inti tista 'tmur b'dan il-mod jew dan il-mod jew il-mod.

1092
00:44:36,920 --> 00:44:39,680
Nistgħu żżomm affarijiet nesting li jmorru f'direzzjonijiet differenti.

1093
00:44:39,680 --> 00:44:41,800
>> Allura Scratch għandha dawn loops, bħal Forever.

1094
00:44:41,800 --> 00:44:44,750
Huwa għandu dawn il-karatteristiċi simili Irrepeti 10, xi

1095
00:44:44,750 --> 00:44:46,260
numru finit ta 'drabi.

1096
00:44:46,260 --> 00:44:49,040
Għandna l-abbiltà issa jiġu stabbiliti varjabbli, hekk f'dan il-każ

1097
00:44:49,040 --> 00:44:51,810
Stajt iddikjarat, per eżempju, kalzetti imsejħa varjabbli.

1098
00:44:51,810 --> 00:44:54,340
Stajt initialized għal 0, u li l-énième direzzjoni

1099
00:44:54,340 --> 00:44:56,940
nistgħu ħadu l hawn ma 'Joseph, fejn forsi I

1100
00:44:56,940 --> 00:45:00,150
biss iżommu rekord ta 'kemm kalzetti nkun fuq u jtemm

1101
00:45:00,150 --> 00:45:03,490
il-programm meta l-valur dak il-varjabbli hija 2.

1102
00:45:03,490 --> 00:45:05,660
Dan ikun mod ieħor ta 'tip ta' jiġġeneralizzaw din

1103
00:45:05,660 --> 00:45:08,820
problema u tagħmel xi ħaġa għal darb'oħra u għal darb'oħra.

1104
00:45:08,820 --> 00:45:12,080
Ukoll, ejja imorru quddiem u issa jintroduċu xi affarijiet ġodda koppja.

1105
00:45:12,080 --> 00:45:14,100
Allura dawk tal inti ma 'esperjenza programing minn qabel se

1106
00:45:14,100 --> 00:45:17,120
jafu li ħafna ta 'lingwi jkollhom arrays, jew il-vetturi jew

1107
00:45:17,120 --> 00:45:19,970
listi, u tabilħaqq, ikollu Scratch xi ħaġa bħal din, wisq.

1108
00:45:19,970 --> 00:45:22,510
Mela ejja ara jekk aħna ma tistax tieħu l-affarijiet għall-livell li jmiss hawn.

1109
00:45:22,510 --> 00:45:24,920
Jekk Għandi l-abbiltà, issa, ma 'dawn il-biċċiet puzzle li

1110
00:45:24,920 --> 00:45:29,080
żid xi ħaġa, bħal kelma jew numru, għal varjabbli, nista '

1111
00:45:29,080 --> 00:45:30,550
jibdew jakkumulaw affarijiet.

1112
00:45:30,550 --> 00:45:33,630
U dan huwa attwalment pretty apropos għal affarijiet bħal logħob,

1113
00:45:33,630 --> 00:45:35,810
irwol-logħob fejn int-tip ta 'mixi madwar

1114
00:45:35,810 --> 00:45:38,600
xi dinja fantasy ġbir affarijiet, picking affarijiet up,

1115
00:45:38,600 --> 00:45:39,900
jaqilgħu punti, jew simili.

1116
00:45:39,900 --> 00:45:42,310
Inti tista 'tixtieq li żżomm rekord ta' xi tip ta 'inventarju, u

1117
00:45:42,310 --> 00:45:45,180
tabilħaqq, dan huwa dak waħda ta 'ex-studenti tagħna hawn għamlet il

1118
00:45:45,180 --> 00:45:47,750
xi ħaġa imsejħa Fruitcraft RPG.

1119
00:45:47,750 --> 00:45:51,820
>> So let me go l quddiem u tiftaħ dan il-ħaġa hawn, u

1120
00:45:51,820 --> 00:45:56,260
Fruitcraft, aħna għandna din id-dinja up fil-quċċata.

1121
00:45:56,260 --> 00:45:58,820
So let me go l quddiem u kklikkja l-bandiera aħdar.

1122
00:45:58,820 --> 00:46:01,040
Avviż fuq quċċata xellug huwa xi tip ta 'inventarju.

1123
00:46:01,040 --> 00:46:04,110
Li implimentati Scratch kif dak li aħna ser sejħa firxa jew

1124
00:46:04,110 --> 00:46:06,890
lista, u issa għandna dan animazzjoni ftit.

1125
00:46:06,890 --> 00:46:10,440
Hekk biss kif bdejna aktar kmieni ma 'din l-istorja imħabba cookie,

1126
00:46:10,440 --> 00:46:13,320
u allura aħna avvanzati għall-qtates u iljuni tal-baħar, issa jista 'jkollna

1127
00:46:13,320 --> 00:46:15,100
affarijiet li huma saħansitra aktar interattiv.

1128
00:46:15,100 --> 00:46:18,250
U dan Guy blu ftit, I tista 'tibda biex jiċċaqalqu tiegħu

1129
00:46:18,250 --> 00:46:19,500
dar ftit hawn.

1130
00:46:19,500 --> 00:46:22,570
Allura jidher qisu hu ltqajna ħruġ stabbiliti hawn, hekk jien jużaw

1131
00:46:22,570 --> 00:46:25,260
l-ċwievet vleġeġ, up, down, xellug dritt.

1132
00:46:25,260 --> 00:46:28,370
U issa jien barra, so let dak li stajt ltqajna hawn.

1133
00:46:28,370 --> 00:46:30,920
Id-Dehra ta 'oranġjo, u tabilħaqq, malli I tmissx il-

1134
00:46:30,920 --> 00:46:33,110
oranġjo, jiġrilha plopped fis-inventarju tiegħi.

1135
00:46:33,110 --> 00:46:35,640
Jekk immur minn hawn il-ċirasa, issa għandi xi ħaġa

1136
00:46:35,640 --> 00:46:36,760
inkella fl-inventarju tiegħi.

1137
00:46:36,760 --> 00:46:39,100
U din hija kollha sbieħ u ħelu, iżda jaħsbu dwar kif, issa, dan

1138
00:46:39,100 --> 00:46:39,840
hija implimentata.

1139
00:46:39,840 --> 00:46:42,490
Well, aħna għandna din l-idea ta 'lista, u li apparentement a

1140
00:46:42,490 --> 00:46:45,470
biċċa puzzle li inti biss jgħidu dak li trid jżidu miegħu, żid

1141
00:46:45,470 --> 00:46:46,950
oranġjo, żid ċirasa.

1142
00:46:46,950 --> 00:46:48,540
Issa, dak li huwa dan Guy blu ftit tagħmel?

1143
00:46:48,540 --> 00:46:49,810
Ukoll, hu tal Sprite.

1144
00:46:49,810 --> 00:46:52,190
U preżumibbilment, il-larinġ u l-ċirasa -

1145
00:46:52,190 --> 00:46:54,140
huma stess kienu sprites separati.

1146
00:46:54,140 --> 00:46:56,980
U l-użu kundizzjonijiet espressjonijiet Boolean, il-

1147
00:46:56,980 --> 00:47:00,530
Student kien probabbilment jistgħu jesprimu IF Guy blu hija

1148
00:47:00,530 --> 00:47:04,590
ċirasa jmissu Imbagħad żid il-ċirasa kelma li tiegħu

1149
00:47:04,590 --> 00:47:07,890
inventarju, u allura wkoll jaħbu l-Sprite ċirasa.

1150
00:47:07,890 --> 00:47:10,600
Allura taħt il-barnuża, hemm probabbilment għadu ċirasa

1151
00:47:10,600 --> 00:47:11,350
Sprite hemmhekk.

1152
00:47:11,350 --> 00:47:14,160
Imxejna biss told din issir b'mod effettiv inviżibbli.

1153
00:47:14,160 --> 00:47:16,340
>> Issa, jekk I iżommu mixi minn hawn, nistgħu wkoll nagħmlu dan

1154
00:47:16,340 --> 00:47:19,150
Ħaġa prossimali, fejn I tista 'tmur u aqra l-sinjal.

1155
00:47:19,150 --> 00:47:23,170
Mela jekk Guy blu jmissu sinjal, li jista 'jkollna din il-blokka Say

1156
00:47:23,170 --> 00:47:26,455
bħad-qattus tkellem lilna fi kliem, bonjour, qabel, "Ghandek

1157
00:47:26,455 --> 00:47:26,880
xi frott?

1158
00:47:26,880 --> 00:47:29,290
Ġib sal-post tal-frott. "Kull dritt, hekk issa, apparentement,

1159
00:47:29,290 --> 00:47:30,550
Għandi direzzjonijiet tiegħi.

1160
00:47:30,550 --> 00:47:33,050
I tista 'tmur fuq hawn fil-post tal-frott, linja up myself

1161
00:47:33,050 --> 00:47:33,740
bil-bieba.

1162
00:47:33,740 --> 00:47:35,390
Issa, jien fil hawn.

1163
00:47:35,390 --> 00:47:38,120
I tista 'tmur sa l-bniedem fuq il-counter.

1164
00:47:38,120 --> 00:47:40,330
Huwa jiskopri li jien qrib tiegħu, u għalhekk ma għandhom ikunu

1165
00:47:40,330 --> 00:47:46,780
pjuttost identiku jmissu, u I rebħu l-logħba.

1166
00:47:46,780 --> 00:47:49,890
Allura hemm aħna għandna Fruitcraft RPG.

1167
00:47:49,890 --> 00:47:52,200
>> Allura nistgħu nagħmlu l-affarijiet aktar avvanzati minn dan.

1168
00:47:52,200 --> 00:47:53,200
Aħna tista 'żżid ħsejjes.

1169
00:47:53,200 --> 00:47:54,610
Aħna tista 'żżid randomness psewdo.

1170
00:47:54,610 --> 00:47:56,260
Aħna tista 'żżid il-kumplessità.

1171
00:47:56,260 --> 00:47:58,490
Let me imorru quddiem hawnhekk, u minflok tagħmel dan myself,

1172
00:47:58,490 --> 00:48:01,240
let me nuruk wieħed mill-sottomissjonijiet aktar sofistikati

1173
00:48:01,240 --> 00:48:06,640
sirna aħħar sena minn xi ħadd ċerti jismu Blake.

1174
00:48:06,640 --> 00:48:08,910
Jista aħna għandna waħda voluntier li huwa komdu li jidhru fuq

1175
00:48:08,910 --> 00:48:12,600
kamera u huwa f'idejn għal playing a game?

1176
00:48:12,600 --> 00:48:13,450
Kif dwar id-dritt hemmhekk?

1177
00:48:13,450 --> 00:48:15,380
Come fuq up.

1178
00:48:15,380 --> 00:48:19,680
Kull dritt, sabiex il-logħba li inti għadek unknowingly

1179
00:48:19,680 --> 00:48:20,780
offriet li jilagħbu -

1180
00:48:20,780 --> 00:48:25,910
[Applause]

1181
00:48:25,910 --> 00:48:28,610
DAVID Malan: - hija xi ħaġa mill-imgħoddi imsejħa

1182
00:48:28,610 --> 00:48:30,100
"Frogger." X'inhu l-isem tiegħek?

1183
00:48:30,100 --> 00:48:30,730
Renda: Renda.

1184
00:48:30,730 --> 00:48:31,050
DAVID Malan: Redna?

1185
00:48:31,050 --> 00:48:32,530
Renda: Huwa simili Brenda ma 'b.

1186
00:48:32,530 --> 00:48:33,190
DAVID Malan: Okay, Renda.

1187
00:48:33,190 --> 00:48:33,590
David.

1188
00:48:33,590 --> 00:48:34,580
Nizza biex jissodisfaw inti.

1189
00:48:34,580 --> 00:48:38,690
>> Allura hawn "Frogger," u jekk nistgħu jgħollu l-volum eżatt

1190
00:48:38,690 --> 00:48:39,780
ftit, inti dan ftit

1191
00:48:39,780 --> 00:48:41,010
Żrinġ aħdar fuq il-qiegħ.

1192
00:48:41,010 --> 00:48:43,940
Tista 'tuża xellug, lemin, u' l isfel, u mira tiegħek huwa li

1193
00:48:43,940 --> 00:48:46,510
jaqsmu l-triq, jaqsmu l-xmara, u tmissx il-pads lily

1194
00:48:46,510 --> 00:48:47,760
fil-quċċata.

1195
00:48:52,090 --> 00:48:53,440
Aw.

1196
00:48:53,440 --> 00:48:54,630
Wieħed aktar t -

1197
00:48:54,630 --> 00:48:56,400
jerġa 'jagħmel, id-dritt?

1198
00:48:56,400 --> 00:48:58,890
Let stop hit s.

1199
00:48:58,890 --> 00:49:00,140
Ħadd ma raw dan.

1200
00:49:10,470 --> 00:49:12,930
[Applause]

1201
00:49:17,023 --> 00:49:17,850
[Applause]

1202
00:49:17,850 --> 00:49:19,341
DAVID Malan: Yeah.

1203
00:49:19,341 --> 00:49:20,832
Tajjeb ħafna x'isir.

1204
00:49:20,832 --> 00:49:22,082
Eċċellenti, grazie.

1205
00:49:27,300 --> 00:49:29,430
>> Allura li kien hemm Frogger. Issa li taf dak li inti stajt

1206
00:49:29,430 --> 00:49:32,170
gotten infuskom fil, voluntier wieħed aktar għal differenti

1207
00:49:32,170 --> 00:49:34,910
logħba sottomessa mill student ieħor.

1208
00:49:34,910 --> 00:49:35,560
Inti tixtieq li ġejjin fuq up?

1209
00:49:35,560 --> 00:49:36,576
X'hemm isem tiegħek?

1210
00:49:36,576 --> 00:49:37,000
RICHARD: Richard.

1211
00:49:37,000 --> 00:49:37,420
DAVID Malan: Richard.

1212
00:49:37,420 --> 00:49:39,732
Kull dritt, Richard, come fuq up.

1213
00:49:39,732 --> 00:49:42,187
[Applause]

1214
00:49:45,140 --> 00:49:47,030
DAVID Malan: Inti għandek xi ħaġa li ser ħoss

1215
00:49:47,030 --> 00:49:54,180
familjari malajr, hekk hawn huma l-istruzzjonijiet tiegħek.

1216
00:49:54,180 --> 00:49:56,580
Allura fil-mument, xi biċċiet puzzle ser iscroll

1217
00:49:56,580 --> 00:49:58,150
mill-iskrin li tfittex jew xellug

1218
00:49:58,150 --> 00:49:59,450
jew dritt jew 'l isfel.

1219
00:49:59,450 --> 00:50:01,230
Int ser ikollok hit-ċwievet vleġġa b'tali mod

1220
00:50:01,230 --> 00:50:04,540
li jikkorrispondi għal dawk il-biċċiet puzzle lining up ma

1221
00:50:04,540 --> 00:50:05,720
il-placeholders fuq quċċata.

1222
00:50:05,720 --> 00:50:07,500
Allura meta tara vleġġa xellug, u li l-linji mat-xellug

1223
00:50:07,500 --> 00:50:09,260
vleġġa, laqat il-vleġġa xellug.

1224
00:50:09,260 --> 00:50:10,866
Inti tista 'tibda.

1225
00:50:10,866 --> 00:50:13,674
[MUSIC - "AKTAR B'SAĦĦTU" Kayne WEST]

1226
00:51:21,222 --> 00:51:23,470
DAVID Malan: Kull dritt, rawnd kbir ta 'applause għall Richard.

1227
00:51:23,470 --> 00:51:26,082
[Applause]

1228
00:51:32,426 --> 00:51:33,720
DAVID Malan: ħafna isir ukoll.

1229
00:51:33,720 --> 00:51:34,110
Grazzi.

1230
00:51:34,110 --> 00:51:37,104
[Applause]

1231
00:51:41,600 --> 00:51:44,330
>> DAVID Malan: gost Allura u, apparentement, tip ta '

1232
00:51:44,330 --> 00:51:46,590
intimidanti kif jista 'jkun li jimplimenta xi ħaġa bħala

1233
00:51:46,590 --> 00:51:49,550
apparentement sofistikata hekk kif dan, tirrealizza li l-istudent

1234
00:51:49,550 --> 00:51:51,450
ma stipulati u biss jikteb dan kollu f'daqqa.

1235
00:51:51,450 --> 00:51:54,200
Pjuttost, inti tista 'tkisser problema kif apparentement kumpless

1236
00:51:54,200 --> 00:51:56,840
kif din f'biċċiet ħafna iżgħar, u dan, ukoll, hija

1237
00:51:56,840 --> 00:51:57,560
ser tkun tema.

1238
00:51:57,560 --> 00:52:00,490
L-agħar ħaġa li tista 'tagħmel fil-kitba ta' programm fil-maġġoranza f'kull

1239
00:52:00,490 --> 00:52:03,480
lingwa huwa li joqogħdu bilqegħda, jiksbu verament eċċitati, ikteb l-

1240
00:52:03,480 --> 00:52:07,200
ħaġa kkritikat kollha, u mbagħad ftit tama li taħdem mill-

1241
00:52:07,200 --> 00:52:08,510
ħin int lest bil-miktub.

1242
00:52:08,510 --> 00:52:10,920
Pjuttost, il-proċess ta 'programmazzjoni għandhom ġeneralment

1243
00:52:10,920 --> 00:52:13,440
jkun ħafna deliberat, ħafna iterattiv, fejn inti biss

1244
00:52:13,440 --> 00:52:16,955
jistabbilixxu passi żgħar ħafna għall infuskom, gidma daqs biċċiet

1245
00:52:16,955 --> 00:52:20,070
tridu li gidma off, u sabiex ikollok dawn sanità

1246
00:52:20,070 --> 00:52:21,740
kontrolli, miri ftit inti tista 'tilħaq.

1247
00:52:21,740 --> 00:52:24,170
U allura inti tibni fuq quċċata ta 'dawk li jinħolqu aktar

1248
00:52:24,170 --> 00:52:25,400
affarijiet sofistikati għadhom.

1249
00:52:25,400 --> 00:52:26,820
>> Għalhekk per eżempju, kif nistgħu tmur dwar

1250
00:52:26,820 --> 00:52:28,380
implimentazzjoni logħba bħal din?

1251
00:52:28,380 --> 00:52:30,160
Ukoll, franchement, I ċertament tibda bi ftit

1252
00:52:30,160 --> 00:52:32,260
appoġġ wieħed ewlieni fi żmien.

1253
00:52:32,260 --> 00:52:34,840
Ejja biss timplimenta l-appoġġ għall-vleġġa xellug.

1254
00:52:34,840 --> 00:52:37,610
Allura l-istudent kellhom b'xi mod joħolqu fil Photoshop, jew

1255
00:52:37,610 --> 00:52:40,340
Scratch ruħha bl-użu editur grafika ftit, l-

1256
00:52:40,340 --> 00:52:42,680
arrow ewlenin li qisu l-wieħed fil-quċċata xellug hemm, biss

1257
00:52:42,680 --> 00:52:43,910
il-griż placeholder.

1258
00:52:43,910 --> 00:52:46,610
Imbagħad l-istudent kellu ċifra barra dak x, y jikkoordinaw biex

1259
00:52:46,610 --> 00:52:48,380
poġġih fejn li tqiegħed lilha fit-tieqa.

1260
00:52:48,380 --> 00:52:50,730
0, 0 hija sa hawn, hekk ikollok biex insemmu l-għadd ta '

1261
00:52:50,730 --> 00:52:53,690
pixels, jew tikek, biex jikkumpensaw dan vleġġa minn

1262
00:52:53,690 --> 00:52:54,800
il-quċċata 'l-iskrin.

1263
00:52:54,800 --> 00:52:57,040
U mbagħad darba li fil-post, il-programm tiegħek ma attwalment

1264
00:52:57,040 --> 00:53:00,380
tagħmel xejn s'issa, sabiex inti mbagħad bżonn Sprite 2, għall-

1265
00:53:00,380 --> 00:53:04,470
eżempju vleġġa ħadra li wkoll tipponta xellug, u inti

1266
00:53:04,470 --> 00:53:06,710
imbagħad għandek bżonn biex tibda bil-miktub xi skripts għal dan.

1267
00:53:06,710 --> 00:53:09,310
>> U tinnota, forsi, li dawn l-affarijiet bdiet ġejjin fil

1268
00:53:09,310 --> 00:53:11,470
veloċitajiet differenti, u l-kuluri kienu differenti

1269
00:53:11,470 --> 00:53:13,750
postijiet, u li għaliex l-istudent użat daqsxejn ta '

1270
00:53:13,750 --> 00:53:14,990
psewdo randomness.

1271
00:53:14,990 --> 00:53:17,440
U billi randomness psewdo, I jfissirx biss pick numru

1272
00:53:17,440 --> 00:53:20,230
bejn xi ħaġa u xi ħaġa għaliex inti tista '

1273
00:53:20,230 --> 00:53:22,890
jibdew affarijiet mappa, simili jekk in-numru huwa bejn wieħed u

1274
00:53:22,890 --> 00:53:24,940
5, ukoll, ejja jagħmlu l-ħaġa aħdar.

1275
00:53:24,940 --> 00:53:28,290
Jekk huwa bejn 6 u 10, ejja jagħmlu l-biċċa puzzle

1276
00:53:28,290 --> 00:53:29,730
aħmar minflok.

1277
00:53:29,730 --> 00:53:31,840
Sakemm ikollok mod ta jiġġeneraw xi tip ta '

1278
00:53:31,840 --> 00:53:34,730
randomness, inti tista 'mbagħad tagħmel deċiżjonijiet ibbażati fuq dik

1279
00:53:34,730 --> 00:53:35,260
randomness.

1280
00:53:35,260 --> 00:53:37,490
U jien iżommu psewdo qal każwali għaliex hemm

1281
00:53:37,490 --> 00:53:38,390
sigrieti maħmuġin ftit.

1282
00:53:38,390 --> 00:53:41,130
Kompjuters ma jistgħux joħorġu bil numri bl-addoċċ.

1283
00:53:41,130 --> 00:53:42,800
Huma jistgħu biss jagħmlu dak li qed told minħabba

1284
00:53:42,800 --> 00:53:44,110
dawn qed magħmula mill-bniedem apparati.

1285
00:53:44,110 --> 00:53:45,880
Huma ma jistgħux sempliċiment raden numru simili aħna bnedmin

1286
00:53:45,880 --> 00:53:46,960
jħossu bħal nistgħu.

1287
00:53:46,960 --> 00:53:50,970
A kompjuter għandu jagħmel xi ħaġa matematiċi li jevokaw l-

1288
00:53:50,970 --> 00:53:53,970
illużjoni ta 'numru matematiċi, xi kultant bl-użu

1289
00:53:53,970 --> 00:53:57,420
jum kurrenti ta 'żmien bħala kontribut għall jidhru dak

1290
00:53:57,420 --> 00:53:59,570
Numru ta 'ritorn, iżda aktar fuq dak ieħor ħin.

1291
00:53:59,570 --> 00:54:02,060
Għal issa, biss jafu li nistgħu jiġġeneraw randomness psewdo.

1292
00:54:02,060 --> 00:54:04,610
>> Allura ladarba għandi l-abbiltà għall-vleġġa xellug biex jibdew

1293
00:54:04,610 --> 00:54:07,990
li jidhru fi żminijiet differenti u b'veloċitajiet differenti, allura

1294
00:54:07,990 --> 00:54:10,230
I tista 'tmur lura u żid xi wħud minn dawn IF kundizzjonijiet.

1295
00:54:10,230 --> 00:54:14,950
JEKK din Sprite qed imiss l-ieħor, u l-vleġġa xellug

1296
00:54:14,950 --> 00:54:16,330
ċavetta ġie ppressat -

1297
00:54:16,330 --> 00:54:17,900
hekk tliet kondizzjonijiet f'dak il-każ.

1298
00:54:17,900 --> 00:54:20,750
I jista 'juża dik U blokk forsi, f'dak il-każ -

1299
00:54:20,750 --> 00:54:23,210
Imbagħad Irrid immur quddiem u inkrement-punteġġ.

1300
00:54:23,210 --> 00:54:25,130
U fil-quċċata, aħna għandna punteġġ, aħna għandna biża ',

1301
00:54:25,130 --> 00:54:26,510
Kessaħ, Good, u Boo.

1302
00:54:26,510 --> 00:54:29,810
Allura hemm apparentament ħames varjabbli li dan l-istudent

1303
00:54:29,810 --> 00:54:32,220
użati biex iżommu kont ta 'dawn metriċi varji.

1304
00:54:32,220 --> 00:54:34,180
Hekk fil-qosor, ir-riżultat aħħari huwa aqwa.

1305
00:54:34,180 --> 00:54:37,320
Huwa gost, huwa gost jilagħbu, huwa l-involviment, iżda dan mhuwiex

1306
00:54:37,320 --> 00:54:38,380
fejn l-istudent beda.

1307
00:54:38,380 --> 00:54:42,210
Hu jew hi bdiet fi sett ħafna iżgħar ta 'passi.

1308
00:54:42,210 --> 00:54:44,470
>> Allura dak li huma xi blokki tal-bini oħra li nistgħu

1309
00:54:44,470 --> 00:54:45,760
nisġa fis-dawn il-programmi?

1310
00:54:45,760 --> 00:54:48,750
Ukoll, hemm dan il-kunċett ieħor fil-lingwi l-aktar,

1311
00:54:48,750 --> 00:54:50,730
Scratch fosthom, magħruf bħala ħjut.

1312
00:54:50,730 --> 00:54:54,660
Allura kompjuter jistgħu attwalment ma verament tagħmel affarijiet multipli fi

1313
00:54:54,660 --> 00:54:56,730
żmien, għall-inqas mhux normalment.

1314
00:54:56,730 --> 00:54:59,930
Pjuttost, kompjuter ġeneralment għandu biss wieħed CPU, u anke

1315
00:54:59,930 --> 00:55:02,230
għalkemm kompjuters huma super fast u jistgħu, għalhekk,

1316
00:55:02,230 --> 00:55:04,740
joħolqu l-illużjoni ta 'affarijiet multipli fuq darba -

1317
00:55:04,740 --> 00:55:06,180
iċċekkjar mail tiegħek, jkollna instant

1318
00:55:06,180 --> 00:55:07,770
, messaġġ istampar dokument -

1319
00:55:07,770 --> 00:55:11,530
verament, kompjuter huwa biss jaqbeż minn istampar biex IMing

1320
00:55:11,530 --> 00:55:15,160
biex email, id-dahar u lura u quddiem u lura tant mgħaġġel li aħna

1321
00:55:15,160 --> 00:55:18,170
bnedmin witted bil-mod biss ma jirrealizzaw li huwa attwalment

1322
00:55:18,170 --> 00:55:21,240
tħaddim ta 'dawk il-programmi ftit kull darba.

1323
00:55:21,240 --> 00:55:23,960
Issa, din id-daqsxejn ta 'bajda jinsabu f'dawn il-jiem għaliex, illum,

1324
00:55:23,960 --> 00:55:26,740
kompjuters ħafna tagħna huma liema huma msejħa multi-core, sabiex inti

1325
00:55:26,740 --> 00:55:29,760
jkollhom waħda CPU iżda cores multipli, li huwa tip ta 'prodotti simili

1326
00:55:29,760 --> 00:55:31,760
jkollhom CPUs multipli.

1327
00:55:31,760 --> 00:55:35,020
>> U għalhekk kultant, kompjuters tista 'verament tagħmel affarijiet multipli

1328
00:55:35,020 --> 00:55:38,500
fi żmien, iżda ġeneralment fi ħdan programm, programmi

1329
00:55:38,500 --> 00:55:40,200
jiddependu fuq dawn l-affarijiet imsejħa ħjut.

1330
00:55:40,200 --> 00:55:43,160
Allura ħajt huwa tip simili ta 'programm minjatura li jistgħu

1331
00:55:43,160 --> 00:55:46,540
jeżistu flimkien mal-programm ieħor ta 'daqs żgħir u tista' taħdem

1332
00:55:46,540 --> 00:55:51,250
b'mod parallel, jew għall-inqas tista 'taħdem taħt l-illużjoni li

1333
00:55:51,250 --> 00:55:52,990
dawn qed taħdem fl-istess ħin.

1334
00:55:52,990 --> 00:55:55,060
Allura Scratch jappoġġja dawn l-affarijiet imsejħa ħjut.

1335
00:55:55,060 --> 00:55:57,580
Inti jista 'jkollhom scripts multipli fuq darba esekuzzjoni, eżatt kif aħna

1336
00:55:57,580 --> 00:56:00,220
kien mal-iljun baħar, u dan jippermetti li fil-fatt

1337
00:56:00,220 --> 00:56:03,620
allura jkollhom interazzjonijiet fost dawn il-sprites.

1338
00:56:03,620 --> 00:56:09,910
Let me imorru quddiem hawn u iġbed up, ejja ngħidu, ħjut, u

1339
00:56:09,910 --> 00:56:11,870
jilagħbu din kif ġej.

1340
00:56:11,870 --> 00:56:13,950
Għandna żewġ sprites, li kull wieħed minnhom aħna ser tara

1341
00:56:13,950 --> 00:56:15,720
għandha wieħed biss iskrittura.

1342
00:56:15,720 --> 00:56:18,000
U tinduna jidher li hemm xi intelliġenza fil-

1343
00:56:18,000 --> 00:56:21,335
qattus f'dan il-wieħed għaliex huwa jkollna aktar mill-qrib -

1344
00:56:21,335 --> 00:56:21,730
[Roars]

1345
00:56:21,730 --> 00:56:24,540
DAVID Malan: - u eqreb lejn l-għasafar ftit.

1346
00:56:24,540 --> 00:56:26,570
>> Allura kif huwa l-operat għasfur?

1347
00:56:26,570 --> 00:56:28,200
Ukoll, ejja tagħti ħarsa lejn l-għasafar l-ewwel.

1348
00:56:28,200 --> 00:56:31,220
L-iskript għasafar qal meta l-bandiera aħdar huwa għafast, mur x

1349
00:56:31,220 --> 00:56:34,020
ugwali negattiv 115 u y ugwali 150.

1350
00:56:34,020 --> 00:56:37,010
So I biss dehret post każwali fejn jien ridt l-

1351
00:56:37,010 --> 00:56:39,580
għasafar li tibda, u I biss plopped lilu hemmhekk mill-kontumaċja.

1352
00:56:39,580 --> 00:56:42,800
Imbagħad Forever IF ma jmissux qattus, għalhekk din hija differenti

1353
00:56:42,800 --> 00:56:45,080
tip ta 'kostruzzjoni looping, iżda istess idea, jagħmlu dan mill-ġdid u

1354
00:56:45,080 --> 00:56:45,780
ġdid u għal darb'oħra.

1355
00:56:45,780 --> 00:56:49,410
Sakemm int ma jmissux il-qattus, jimxu tliet passi, u

1356
00:56:49,410 --> 00:56:51,680
jekk int fuq it-tarf, bounce, fejn huwa tip ta '

1357
00:56:51,680 --> 00:56:53,320
riflessjoni fis-sens tal-biljard.

1358
00:56:53,320 --> 00:56:56,140
Allura li kif l-għasfur miexja madwar tip ta '

1359
00:56:56,140 --> 00:56:58,890
apparentement addoċċ, imma huwa biss għaliex dan huwa bouncing off

1360
00:56:58,890 --> 00:57:00,170
il-ħitan f'dan il-każ.

1361
00:57:00,170 --> 00:57:03,170
>> Issa l-qattus, sadanittant, hija tip ta 'qerq.

1362
00:57:03,170 --> 00:57:05,520
Il-qattus, meta l-bandiera aħdar huwa għafast, iva, jibda fl-

1363
00:57:05,520 --> 00:57:07,390
xi post, post każwali -

1364
00:57:07,390 --> 00:57:09,590
inqas parzjalment bħala kull l-pick

1365
00:57:09,590 --> 00:57:11,430
blokk aħdar każwali hemm -

1366
00:57:11,430 --> 00:57:14,660
u mbagħad Forever IF li jmissu l-għasafar, jilagħbu l-ħoss iljun,

1367
00:57:14,660 --> 00:57:15,790
u imbagħad jieqaf iskrittura.

1368
00:57:15,790 --> 00:57:18,560
Allura meta I said jtemm, jew joħroġ qabel, hemm puzzle

1369
00:57:18,560 --> 00:57:20,600
biċċa fil Scratch li se biss joqtlu l-programm f'dak

1370
00:57:20,600 --> 00:57:22,900
punt għaliex dan huwa tip ta 'loġikament isir.

1371
00:57:22,900 --> 00:57:25,030
Iżda xorta, hawn, l-avviż x'inhu jiġri.

1372
00:57:25,030 --> 00:57:28,470
Punt lejn l-għasafar u jimxu pass wieħed.

1373
00:57:28,470 --> 00:57:31,390
Allura dan il-punt lejn l-għasafar huwa tip ta 'vantaġġ l-qattus

1374
00:57:31,390 --> 00:57:34,640
għandha f'dik huwa homing fil dwar l-għasafar jiċċaqalqu, u nistgħu

1375
00:57:34,640 --> 00:57:37,370
Issa jagħmlu dan il-programm l-aktar interessanti.

1376
00:57:37,370 --> 00:57:41,520
Minflok li jiċċaqalqu pass wieħed fi żmien għal kull ċiklu CPU, kull

1377
00:57:41,520 --> 00:57:44,280
istrajk pedaġġ tal-qanpiena, biex ngħidu hekk, let me imorru quddiem u

1378
00:57:44,280 --> 00:57:47,350
jiċċaqalqu, ejja ngħidu, ħames passi fi żmien bħala l-qattus.

1379
00:57:47,350 --> 00:57:51,120
Ikklikkja run, u issa huwa verament jsib lilu malajr.

1380
00:57:51,120 --> 00:57:55,620
Jekk aħna tirdoppja din wara 10 passi, li tip ta 'tmur

1381
00:57:55,620 --> 00:57:56,370
dritt għalih.

1382
00:57:56,370 --> 00:57:57,750
Issa, nistgħu nagħtu l-għasafar,

1383
00:57:57,750 --> 00:57:59,540
forsi, daqsxejn ta 'vantaġġ.

1384
00:57:59,540 --> 00:58:02,370
Ejja mur l-għasafar u jgħidu minflok ta 'ċaqliq tliet passi,

1385
00:58:02,370 --> 00:58:07,140
ejja jimxu lilu 30 passi.

1386
00:58:07,140 --> 00:58:08,700
Imma hu għadu ltqajna maqbuda fl-aħħar.

1387
00:58:08,700 --> 00:58:10,430
>> Allura hawnhekk, għandna żewġ ħjut.

1388
00:58:10,430 --> 00:58:13,230
Huwa ħabs fil Scratch ma 'żewġ skripts u żewġ

1389
00:58:13,230 --> 00:58:16,150
sprites, iżda l-idea f'lingwi oħra hija li inti tista '

1390
00:58:16,150 --> 00:58:19,220
jiktbu, essenzjalment, programmi wisq bħal dan u għandhom

1391
00:58:19,220 --> 00:58:22,950
lilhom jimxu verament, jew imaginarily, b'mod parallel.

1392
00:58:22,950 --> 00:58:25,280
>> Issa, hemm ukoll dan il-kunċett fil-programmazzjoni magħrufa bħala

1393
00:58:25,280 --> 00:58:28,010
avvenimenti, u din hija xi ħaġa li aħna mhux se tara fis-C, il-

1394
00:58:28,010 --> 00:58:30,500
lingwa magħrufa bħala C. Aħna se tara li lejn tmiem is-semestru ta

1395
00:58:30,500 --> 00:58:33,240
fl-ipprogrammar tal-web, meta aħna nintroduċu JavaScript u l-

1396
00:58:33,240 --> 00:58:36,970
kunċett ta 'paġni tal-web tal-bini li huma dinamiċi u jinteraġixxu

1397
00:58:36,970 --> 00:58:37,710
ma 'utenti.

1398
00:58:37,710 --> 00:58:40,430
Allura f'dan il-każ, aħna għandna eżempju sempliċi ħafna ta '2

1399
00:58:40,430 --> 00:58:43,860
sprites, tifel u tifla, li kull wieħed minnhom ikollu rispettivi tagħhom

1400
00:58:43,860 --> 00:58:48,040
ħjut, iżda b'xi dawn iż-żewġ huma inter-komunikazzjoni permezz

1401
00:58:48,040 --> 00:58:49,490
ta 'xi ħaġa imsejħa avvenimenti.

1402
00:58:49,490 --> 00:58:52,750
So let me aqbad hawn u zoom fuq iskrittura tal-boy,

1403
00:58:52,750 --> 00:58:54,050
li tidher bħal dan.

1404
00:58:54,050 --> 00:58:57,510
Meta bandiera aħdar għafast, dejjem jagħmel dan li ġej.

1405
00:58:57,510 --> 00:59:01,510
Jekk l-Ispazju ewlenin, jew l-Avukatura Ispazju, hija ppressata, ngħidu

1406
00:59:01,510 --> 00:59:03,900
Marco għal żewġ sekondi, li l-purament estetiċi fuq il-

1407
00:59:03,900 --> 00:59:06,860
iskrin, buzzieqa diskors ftit, iżda mbagħad mxandra.

1408
00:59:06,860 --> 00:59:09,240
>> Allura xandira ieħor huwa biċċa Scratch li l-

1409
00:59:09,240 --> 00:59:12,050
rappreżentant ta 'klassi ta' funzjonalità fil-programmazzjoni

1410
00:59:12,050 --> 00:59:15,080
li tippermetti programmi differenti, ħjut differenti,

1411
00:59:15,080 --> 00:59:17,120
biex inter-komunikazzjoni, biex b'xi mod jibagħtu

1412
00:59:17,120 --> 00:59:18,520
messaġġi, wieħed għall-ieħor.

1413
00:59:18,520 --> 00:59:21,930
Tgħaddi biċċa karta fil-klassi huwa tip ta 'l-teknoloġija baxxa

1414
00:59:21,930 --> 00:59:22,700
ekwivalenti.

1415
00:59:22,700 --> 00:59:24,300
Allura xandira avveniment.

1416
00:59:24,300 --> 00:59:26,210
I tista 'tibgħat dan il-messaġġ, u l-avveniment kelma

1417
00:59:26,210 --> 00:59:27,270
huwa kompletament arbitrarju.

1418
00:59:27,270 --> 00:59:30,000
Scratch kultant għandha dawn downs qatra, so I biss ħarāet

1419
00:59:30,000 --> 00:59:33,230
ma 'kelma każwali bħal avveniment għaliex issa, dak li l-boy ma

1420
00:59:33,230 --> 00:59:36,600
meta I agħfas il-muftieħ huwa li xandiriet dan l-avveniment.

1421
00:59:36,600 --> 00:59:39,270
U jekk I ħarsa issa fil iskrittura l-tifla, b'kitba tagħha huwa

1422
00:59:39,270 --> 00:59:42,690
super sempliċi għaliex kollha hi teħtieġ li tagħmel huwa li ma jaġixxux meta

1423
00:59:42,690 --> 00:59:44,100
l-bandiera aħdar huwa għafast.

1424
00:59:44,100 --> 00:59:47,910
Hija mfassla biex azzjoni meta hija tirċievi, kwotazzjoni unquote,

1425
00:59:47,910 --> 00:59:51,210
"Avveniment", u f'dak il-punt, hi tal smigħ għalhekk

1426
00:59:51,210 --> 00:59:52,960
l-avveniment hekk imsejħa għal darb'oħra u għal darb'oħra.

1427
00:59:52,960 --> 00:59:55,790
Hekk kif hija tirċievi il-każ, hi għaddej biex shout

1428
00:59:55,790 --> 00:59:57,680
Polo għal żewġ sekondi.

1429
00:59:57,680 --> 01:00:01,090
>> U għalhekk inti tista 'forsi jiġi dedott minn dan eżattament dak li l-

1430
01:00:01,090 --> 01:00:03,190
riżultat li jmiss se tkun.

1431
01:00:03,190 --> 01:00:04,910
Let me ikklikkja l-bandiera aħdar.

1432
01:00:04,910 --> 01:00:06,610
Xejn jiġri minħabba I bżonn tagħmel dak?

1433
01:00:06,610 --> 01:00:07,310
UDJENZA: Bar Ispazju.

1434
01:00:07,310 --> 01:00:08,630
DAVID Malan: Bar Ispazju.

1435
01:00:08,630 --> 01:00:11,990
Boy jgħid Marco, girl jgħid Polo.

1436
01:00:11,990 --> 01:00:13,670
Iżda li mhux iebes kodifikati per se.

1437
01:00:13,670 --> 01:00:16,740
Li inter-komunikazzjoni bejn skripts, hekk issa għandna

1438
01:00:16,740 --> 01:00:19,240
għandhom il-ħila li jagħmlu programmi aktar kumplessi fejn

1439
01:00:19,240 --> 01:00:22,830
dawn iż-żewġ huma b'xi mod inter-komunikazzjoni.

1440
01:00:22,830 --> 01:00:25,260
>> Allura f'liema direzzjonijiet nistgħu jieħdu din?

1441
01:00:25,260 --> 01:00:28,260
Ukoll, fl-sett problema 0, verament, l-għan huwa li

1442
01:00:28,260 --> 01:00:29,830
jieħdu pjaċir bil Scratch.

1443
01:00:29,830 --> 01:00:32,440
Għall-edizzjoni Hacker, inti ser minflok tieħdu gost ma 'aktar

1444
01:00:32,440 --> 01:00:35,850
verżjoni sofistikati ta Scratch imsejħa BYOB, Ibni

1445
01:00:35,850 --> 01:00:38,040
Blokki Your Own, iżda l-idea hija l-istess.

1446
01:00:38,040 --> 01:00:38,780
Int ser tkun kapaċi -

1447
01:00:38,780 --> 01:00:39,710
Iva, li kien intenzjonat.

1448
01:00:39,710 --> 01:00:42,450
Daħal minn Berkeley.

1449
01:00:42,450 --> 01:00:45,200
BYOB hija l-verżjoni edizzjoni Hacker ta 'dan, iżda t-tnejn

1450
01:00:45,200 --> 01:00:48,180
demografija, edizzjoni standard u edizzjoni Hacker simili, il-

1451
01:00:48,180 --> 01:00:50,940
mira fil-idejn għall-ġimgħa li ġejjin huwa verament ftit li adsa fil

1452
01:00:50,940 --> 01:00:53,050
fond, nikseb idejk maħmuġa bil-programmazzjoni, u jagħmlu

1453
01:00:53,050 --> 01:00:55,240
xi ħaġa interessanti, jagħmlu xi ħaġa interattivi, jagħmlu

1454
01:00:55,240 --> 01:00:58,020
xi ħaġa artistiċi, jagħmluhom gost xi ħaġa li fil-fatt

1455
01:00:58,020 --> 01:01:01,020
juri, b'mod li sa tmiem il-ġimgħa, inti ser ikollok proġett,

1456
01:01:01,020 --> 01:01:03,770
mhux biss għall-ewwel CS50 tiegħek pset, iżda inti ser ikollok

1457
01:01:03,770 --> 01:01:05,620
ftit xi ħaġa li inti tista 'turi off fil Annenberg biex

1458
01:01:05,620 --> 01:01:08,830
ħbieb jew saħansitra tal-familja mill uploading għall-websajt MIT.

1459
01:01:08,830 --> 01:01:11,760
U hekk kif għidt nhar l-Erbgħa, nistennew 90% tal-klassi,

1460
01:01:11,760 --> 01:01:13,970
ġeneralment, biex jagħmlu l-edizzjonijiet standard.

1461
01:01:13,970 --> 01:01:16,660
Tirrealizza li hemm ukoll dan is-suq għal dawk minnkom li

1462
01:01:16,660 --> 01:01:18,990
kieku ssib ruħek daqsxejn bored mal-punti bażiċi

1463
01:01:18,990 --> 01:01:21,650
u verament irridu li adsa u inġenji ta 'viżjoni inti diġà

1464
01:01:21,650 --> 01:01:25,380
jkollhom bi sfond qabel f'dan aktar faċli

1465
01:01:25,380 --> 01:01:26,240
ambjent.

1466
01:01:26,240 --> 01:01:29,030
>> So let me pull up eżempju wieħed ieħor li wieħed mill-ex tagħna

1467
01:01:29,030 --> 01:01:33,830
studenti hawnhekk ma u għid ftit xi ħaġa permezz kanzunetta.

1468
01:01:33,830 --> 01:01:37,430
Dan bl-istess mod, kif dan jilgħab, jaħsbu dwar kif inti tmur dwar

1469
01:01:37,430 --> 01:01:40,520
implimentazzjoni ta 'dan il-programm bl-użu preċiżament dawn istess

1470
01:01:40,520 --> 01:01:44,180
building blocks, xi ftit ta 'randomness psewdo, u ta'

1471
01:01:44,180 --> 01:01:46,010
daqsxejn ta 'kanzunetta familjari.

1472
01:01:46,010 --> 01:01:47,910
Jekk nistgħu jgħollu l-volum biss ftit?

1473
01:01:47,910 --> 01:01:49,160
[MUSIC - "IT'S AĦRIĠ IRĠIEL" IL BNIET TEMP]

1474
01:03:02,261 --> 01:03:03,930
>> DAVID Malan: Li lilha għall CS50.

1475
01:03:03,930 --> 01:03:05,860
Aħna se tara int nhar it-Tnejn.

1476
01:03:05,860 --> 01:03:21,152
[Applause]