1 00:00:00,000 --> 00:00:02,742 >> [Daqq tal-mużika] 2 00:00:02,742 --> 00:00:05,030 3 00:00:05,030 --> 00:00:09,090 >> ANDI Peng: Dan huwa CS50, u merħba lill ġimgħatejn tas-sezzjoni. 4 00:00:09,090 --> 00:00:11,740 Dan huwa attwalment filwaqt ġimgħa tnejn mill class-- tagħna attwalment, 5 00:00:11,740 --> 00:00:14,550 l-ewwel ġimgħa aħna kellna taqsima. 6 00:00:14,550 --> 00:00:18,897 Turija tal-idejn, kemm tal inti kollha waslet għall-taqsima super aħħar ġimgħa? 7 00:00:18,897 --> 00:00:19,480 OK, dan huwa OK. 8 00:00:19,480 --> 00:00:20,020 Li OK. 9 00:00:20,020 --> 00:00:23,110 Kemm inti qiegħed jarah super taqsima ġimgħa li għaddiet? 10 00:00:23,110 --> 00:00:23,610 KOLLOX SEW. 11 00:00:23,610 --> 00:00:25,702 U inti guys ma multa fuq problema sett wieħed? 12 00:00:25,702 --> 00:00:28,660 Hekk jien ser teħodha li għandna mazz ta 'tfal verament intelliġenti 13 00:00:28,660 --> 00:00:32,310 f'din il-klassi u l-affarijiet se tkun multa. 14 00:00:32,310 --> 00:00:33,180 KOLLOX SEW. 15 00:00:33,180 --> 00:00:33,980 Allura first-- 16 00:00:33,980 --> 00:00:37,900 17 00:00:37,900 --> 00:00:41,090 >> L-ewwel, aħna qed biss ser qosor jmorru fuq l-aġenda għal-lum. 18 00:00:41,090 --> 00:00:42,700 Aħna ser jitkellmu dwar loġistika kors. 19 00:00:42,700 --> 00:00:45,480 A lott ta 'inti probabilment jkollha mistoqsijiet dwar in 20 00:00:45,480 --> 00:00:46,920 kif l-affarijiet jimxu f'dan il-kors. 21 00:00:46,920 --> 00:00:47,897 Aħna ser tweġibhom. 22 00:00:47,897 --> 00:00:49,730 Aħna qed tmur biex fil-qosor jmorru fuq loops fil-każ 23 00:00:49,730 --> 00:00:51,410 kwalunkwe inti guys qbiżt sezzjoni super. 24 00:00:51,410 --> 00:00:53,240 Aħna ser jitkellmu dwar mapping ASCII. 25 00:00:53,240 --> 00:00:56,180 Aħna ser jitkellmu dwar arrays, funzjonijiet, argumenti kmand linja. 26 00:00:56,180 --> 00:01:00,210 U fl-aħħarnett, dak li inti guys probabbilment kollha verament tixtieq li tkun hawn biex jitgħallmu dwar, 27 00:01:00,210 --> 00:01:01,270 huwa pset2 tiegħek. 28 00:01:01,270 --> 00:01:04,209 Aħna ser ikollhom xi tricks sbieħ u pariri għall kif għandek tagħmel dan. 29 00:01:04,209 --> 00:01:07,910 30 00:01:07,910 --> 00:01:08,690 >> KOLLOX SEW. 31 00:01:08,690 --> 00:01:11,450 Ukoll, it-tieni, għandna lottijiet ta 'kandju hawn. 32 00:01:11,450 --> 00:01:13,583 Xi ħadd li jħobb kandju, biss toħroġ hawn. 33 00:01:13,583 --> 00:01:14,430 Grab xi. 34 00:01:14,430 --> 00:01:15,100 I jkollhom mazz. 35 00:01:15,100 --> 00:01:16,390 Għandna tunnellata fl-uffiċċju. 36 00:01:16,390 --> 00:01:18,230 I ma verament irridu li jieklu kandju ġurnata kollha. 37 00:01:18,230 --> 00:01:20,300 You guys għandhom jieklu l-kandju, minħabba I miġjuba hawn għalik guys. 38 00:01:20,300 --> 00:01:20,990 Just jieklu kandju. 39 00:01:20,990 --> 00:01:24,080 Se jkun hemm kull sezzjoni kandju. 40 00:01:24,080 --> 00:01:25,330 >> Allura l-ewwel, li jien? 41 00:01:25,330 --> 00:01:27,080 Jisimni Andi Peng. 42 00:01:27,080 --> 00:01:30,270 I am il-kap TA tat CS50 hawn fuq Yale. 43 00:01:30,270 --> 00:01:32,540 U flimkien ma ' dan, I se be-- wkoll 44 00:01:32,540 --> 00:01:35,600 jekk xi ħadd ikun like-- running tiegħek buddy, l-ispalla tiegħek cry fuq. 45 00:01:35,600 --> 00:01:39,140 Jekk il-lejl ta 'qabel minħabba pset tiegħek, ikollok l-ebda idea x'inhu għaddej, 46 00:01:39,140 --> 00:01:40,080 hit me up. 47 00:01:40,080 --> 00:01:42,770 Aħna ser commiserate flimkien, eċċetera. 48 00:01:42,770 --> 00:01:46,100 Just jafu li jien hawn bħala riżorsi għalik bħala l-linja ta 'quddiem 49 00:01:46,100 --> 00:01:51,830 fil tgħinek guys figura kif sabiex isolvu problemi fil CS50 u lil hinn. 50 00:01:51,830 --> 00:01:54,590 >> Email tiegħi huwa andi.peng@yale.edu. 51 00:01:54,590 --> 00:01:58,390 I ser ukoll jibgħat individwu email bin-numru tat-telefon tiegħi fiha 52 00:01:58,390 --> 00:02:01,860 hekk li mhux kulħadd fuq il- internet jista 'jara numru tat-telefon tiegħi. 53 00:02:01,860 --> 00:02:03,640 Ħossok liberu li isejħuli fi kwalunkwe ħin. 54 00:02:03,640 --> 00:02:07,510 Serjament, telefon tiegħi huwa normalment mehmuża mal-naħa tiegħi. 55 00:02:07,510 --> 00:02:10,240 I jistgħu ma jirrispondux fi ftit minuti. 56 00:02:10,240 --> 00:02:11,984 I ma jista 'jwieġeb fi żmien ftit sigħat. 57 00:02:11,984 --> 00:02:14,400 Imma nista 'garanzija li inti, jekk inti e-mail lili, jekk inti isejħuli, 58 00:02:14,400 --> 00:02:17,404 test me, I ser tirrispondi fi żmien 24 siegħa. 59 00:02:17,404 --> 00:02:19,820 Oftentimes, I ser jirrispondu qabel li, minħabba nifhem 60 00:02:19,820 --> 00:02:23,900 li kulħadd ltqajna xi problemi, u inti tixtieq tweġibiet tiegħek 61 00:02:23,900 --> 00:02:26,110 li tiġi mwieġba malajr ħafna. 62 00:02:26,110 --> 00:02:28,945 >> Madankollu, jekk inti sejħa me 30 minuta qabel 63 00:02:28,945 --> 00:02:31,570 li l-biċċa li tkun il-Ħamis dovut night-- jkunu simili, Andi, għinni, 64 00:02:31,570 --> 00:02:35,380 I ma started-- I jista 'jagħti inti li ispalla cry fuq. 65 00:02:35,380 --> 00:02:41,520 Iżda jista 'jkun żmien biex jaħsbu dwar kif ma tagħmel dan ħin li jmiss. 66 00:02:41,520 --> 00:02:44,040 KOLLOX SEW. 67 00:02:44,040 --> 00:02:44,944 Oops. 68 00:02:44,944 --> 00:02:45,850 Kif nista tmur lura? 69 00:02:45,850 --> 00:02:48,140 Hemm immorru. 70 00:02:48,140 --> 00:02:52,310 >> Allura f'dan il-kors, aħna għandna tunnellata ta 'appoġġ għal kulħadd. 71 00:02:52,310 --> 00:02:54,640 Minbarra għal ftit sezzjonijiet hawn, li inti 72 00:02:54,640 --> 00:02:57,000 kull ġimgħa tikseb biex jonfqu 90 minuti isbaħ miegħi, 73 00:02:57,000 --> 00:02:58,330 irridu wkoll ħinijiet tal-uffiċċju. 74 00:02:58,330 --> 00:03:01,021 Kemm inti guys diġà kien li ħinijiet tal-uffiċċju għall-għajnuna? 75 00:03:01,021 --> 00:03:01,520 Great. 76 00:03:01,520 --> 00:03:05,700 Li verament tajba biex tara, għaliex aħna staff ta 'aktar minn 45 TAs u CAs 77 00:03:05,700 --> 00:03:11,780 mħarrġa għal dan il-kors li qegħdin hawn għall tgħinek guys ma psets tiegħek. 78 00:03:11,780 --> 00:03:14,580 >> Tnejn li qed isiru fil-TEAL klassi fi 17 Hill House hawn 79 00:03:14,580 --> 00:03:15,350 fil-Yale. 80 00:03:15,350 --> 00:03:17,349 Tlieta u l-Ħamis, dawn qed saret commons. 81 00:03:17,349 --> 00:03:20,010 8:00-11:00 pretty ħafna kull ġimgħa. 82 00:03:20,010 --> 00:03:21,620 Jidħlu fi, toħroġ. 83 00:03:21,620 --> 00:03:24,030 Kwalunkwe problema, l-ebda problem-- kemm toħroġ fi, 84 00:03:24,030 --> 00:03:26,650 u mbagħad aħna ser jgħinuk out ma 'dak. 85 00:03:26,650 --> 00:03:31,640 >> It-tieni nett, minbarra l-ħinijiet uffiċċju u sezzjonijiet, irridu wkoll shorts. 86 00:03:31,640 --> 00:03:35,930 Has ħadd qatt rat koppja tal- xorts jew walkthroughs fil-videos 87 00:03:35,930 --> 00:03:36,750 fuq il-websajt? 88 00:03:36,750 --> 00:03:37,250 KOLLOX SEW. 89 00:03:37,250 --> 00:03:39,510 Allura jkunu tassew, tassew utli. 90 00:03:39,510 --> 00:03:42,470 Produzzjoni tagħna Harvard sabiħ tim hemmhekk fuq dik l-iskola 91 00:03:42,470 --> 00:03:47,910 up tramuntana, huma iffilmjati u prodotti dawn il-videos walkthrough inkredibbli. 92 00:03:47,910 --> 00:03:52,290 >> Huma ser tieħdok pass pass permezz kif għanddu isolvi problema. 93 00:03:52,290 --> 00:03:56,340 Oftentimes, jekk int konfuż dwar kunċett sempliċi, kunċett singular, 94 00:03:56,340 --> 00:03:59,780 tagħti ħarsa, għaliex aħna probabilment jkollhom qasir fuqha x'imkien fuq il-websajt tagħna. 95 00:03:59,780 --> 00:04:03,800 U huwa normalment kbira tar-riżorsi biex tfittex meta int l-ewwel 96 00:04:03,800 --> 00:04:06,510 mitlufa fuq kif iqandlu problema. 97 00:04:06,510 --> 00:04:09,750 >> It-tielet, irridu wkoll study50 u reference50. 98 00:04:09,750 --> 00:04:15,650 Allura istudju 50 fuq il- websajt hija biss rabta. 99 00:04:15,650 --> 00:04:21,500 Huwa, I think, study.cs50.net jew xi ħaġa bħal dik. 100 00:04:21,500 --> 00:04:22,860 Just google dan. 101 00:04:22,860 --> 00:04:24,229 Għandna lottijiet ta 'slides ppreparati. 102 00:04:24,229 --> 00:04:26,770 Għandna lottijiet ta 'shorts u affarijiet walkthroughs-- kollha kkompilati 103 00:04:26,770 --> 00:04:31,070 sabiħ ħafna u pulita għalik guys kollha li tfittex permezz, tara l-ebda kunċetti 104 00:04:31,070 --> 00:04:32,860 li int konfuż dwar. 105 00:04:32,860 --> 00:04:35,920 Probabbilment d jkun kopert hemmhekk fil study50. 106 00:04:35,920 --> 00:04:37,640 >> Reference50-- simili. 107 00:04:37,640 --> 00:04:41,510 Għandna ħafna ta 'noti differenti faċilment disponibbli għar-rimi tiegħek. 108 00:04:41,510 --> 00:04:44,450 U fl-aħħarnett, aħna għandna x'hemm imsejħa CS50 Iddiskuti, 109 00:04:44,450 --> 00:04:48,082 forum li fih, jekk il-lejl ta 'qabel li qed isir problemi tiegħek, jgħidu, 110 00:04:48,082 --> 00:04:49,880 Għandek xi mistoqsija. 111 00:04:49,880 --> 00:04:52,340 Log in to CS50 Iddiskuti. 112 00:04:52,340 --> 00:04:53,190 Post mistoqsija tiegħek. 113 00:04:53,190 --> 00:04:55,820 U allura wieħed mill-hundreds-- forsi, thousands-- ta 'sħabhom 114 00:04:55,820 --> 00:04:57,960 tieħu online din il-klassi se log in. 115 00:04:57,960 --> 00:05:01,182 U forsi xi ħadd jistgħu jiksbu tweġiba tiegħek qabel jista AT. 116 00:05:01,182 --> 00:05:03,390 Huwa essenzjalment biss forum online li aħna kollha jistgħu 117 00:05:03,390 --> 00:05:04,556 jużaw biex jiddiskutu problemi tagħna. 118 00:05:04,556 --> 00:05:06,483 Li jibred. 119 00:05:06,483 --> 00:05:10,660 120 00:05:10,660 --> 00:05:11,550 >> KOLLOX SEW. 121 00:05:11,550 --> 00:05:13,220 Allura problema settijiet. 122 00:05:13,220 --> 00:05:17,840 Aħna dwar id-dritt fil- oħxon ta 'problema sett tnejn. 123 00:05:17,840 --> 00:05:20,570 Ħafna minna għandna diġà tħabtu permezz problema sett wieħed. 124 00:05:20,570 --> 00:05:24,460 Aħna diġà jafu li forsi stennija għall-aħħar lejl biex jagħmlu pset tiegħek 125 00:05:24,460 --> 00:05:28,170 mhuwiex il-ħaġa smartest li tagħmel fil CS50. 126 00:05:28,170 --> 00:05:32,380 >> Għajnuniet u pariri essenzjalment għall suċċess jinqraw l-spec kollu. 127 00:05:32,380 --> 00:05:36,270 Kemm inti diġà aqra l-spec għall pset 2? 128 00:05:36,270 --> 00:05:36,770 KOLLOX SEW. 129 00:05:36,770 --> 00:05:39,840 Li l-ammont solidu. 130 00:05:39,840 --> 00:05:43,210 Naf li inti guys probabilment rikonoxxuti minn issa l-specs huma verament twila. 131 00:05:43,210 --> 00:05:45,700 Huma qed verament, verament twila. 132 00:05:45,700 --> 00:05:49,630 >> Huwa tassew diffiċli biex jinqara kull linja ta 'dak b'attenzjoni kelma b'kelma. 133 00:05:49,630 --> 00:05:52,780 Inti tixtieq li sempliċiment skim fejn hija jgħidlek biex tagħmel xi ħaġa. 134 00:05:52,780 --> 00:05:54,459 I jistgħu jiggarantixxu inti, ma tagħmel dan. 135 00:05:54,459 --> 00:05:56,750 Jekk inti tagħmel dan, int probabilment ser jitlef x'imkien 136 00:05:56,750 --> 00:05:58,458 fejn hija jgħidlek kif tibda problema 137 00:05:58,458 --> 00:06:01,140 jew hija jgħidlek x'għandek isem problema tiegħek jew hija jgħidlek, 138 00:06:01,140 --> 00:06:03,720 dan huwa probabbilment l-aħjar mod biex jibdew jagħmlu problema tiegħek. 139 00:06:03,720 --> 00:06:05,050 U allura inti ser tintilef. 140 00:06:05,050 --> 00:06:08,219 >> Meta inti tipprova taqra tiegħek spec fin-nofs permezz, 141 00:06:08,219 --> 00:06:10,510 ħafna mill-importanti information-- f'dak int mhux 142 00:06:10,510 --> 00:06:12,260 ser tkun tista 'verament aċċess. 143 00:06:12,260 --> 00:06:13,219 Allura taqra l-spec kollu. 144 00:06:13,219 --> 00:06:15,468 Ipprova biex taqra l-spec kollu qabel ma jaslu għal taqsima, 145 00:06:15,468 --> 00:06:17,360 għaliex imbagħad, meta aħna jitkellmu dwar il-pset, 146 00:06:17,360 --> 00:06:21,070 aħna kollha jista 'jkollhom idea tal x'inhu għaddej. 147 00:06:21,070 --> 00:06:25,169 >> It-tieni nett, dan huwa kunċett li jien ser simili li referenza 148 00:06:25,169 --> 00:06:26,710 ħafna matul il-semestru kors. 149 00:06:26,710 --> 00:06:30,070 Iżda essenzjalment, jiltaqa magħna fin-nofs, right? 150 00:06:30,070 --> 00:06:33,970 Me, kif TA tiegħek u Jason bħala kors maniġer u Scaz bħala professur tiegħek 151 00:06:33,970 --> 00:06:37,120 u David bħala professur tiegħek u kollha ta ' l TAs sabiħ oħra f'dan kors, 152 00:06:37,120 --> 00:06:39,830 assistenti f'dan course-- aħna se nagħmlu l-almu tagħna 153 00:06:39,830 --> 00:06:42,965 biex jiżguraw li inti huma stabbiliti sa tirnexxi f'dan il-kors. 154 00:06:42,965 --> 00:06:43,840 Aħna se torganizza sezzjoni. 155 00:06:43,840 --> 00:06:44,870 Aħna se torganizza ħinijiet tal-uffiċċju. 156 00:06:44,870 --> 00:06:47,087 Aħna se twieġeb il-mobile tiegħek jappella, twieġeb e-mails tiegħek, 157 00:06:47,087 --> 00:06:49,670 tagħmel dak kollu li nistgħu biex tagħmel żgur mistoqsijiet tiegħek jitwieġbu. 158 00:06:49,670 --> 00:06:51,460 >> Madankollu, tgħinna out wisq. 159 00:06:51,460 --> 00:06:52,450 Jiltaqa magħna nofs. 160 00:06:52,450 --> 00:06:56,040 Jekk inti tidħol għall ħinijiet tal-uffiċċju li ma marret it-taqsima, mhux 161 00:06:56,040 --> 00:07:02,060 wara li rat il-lectures, li m'għandha ebda idea x'inhu għaddej, tkun simili, għinni. 162 00:07:02,060 --> 00:07:04,350 Jien se tkun simili, ukoll, jien sorry. 163 00:07:04,350 --> 00:07:06,410 Jista 'jkun żmien li jsellef li ispalla cry fuq, 164 00:07:06,410 --> 00:07:08,959 għaliex jien ċert dak I tista 'tagħmel biex jgħinuk 165 00:07:08,959 --> 00:07:12,000 jekk inti ma tippruvax li inqas għajnuna yourself ftit fil-bidu. 166 00:07:12,000 --> 00:07:12,910 Jiltaqa magħna nofs. 167 00:07:12,910 --> 00:07:15,020 You know, jekk jogħġbok come lest biex jitwieġbu u jiksbu 168 00:07:15,020 --> 00:07:16,353 lest li jidħlu fil-materjal. 169 00:07:16,353 --> 00:07:19,342 Hija tagħmel affarijiet daqshekk aktar faċli għal kulħadd involut. 170 00:07:19,342 --> 00:07:22,970 Yeah, dan huwa pretty ħafna dan. 171 00:07:22,970 --> 00:07:23,720 >> Gradazzjoni. 172 00:07:23,720 --> 00:07:29,250 Allura fuq il-sillabu, huwa pjuttost fil-fond dwar kif aħna grad. 173 00:07:29,250 --> 00:07:32,440 Iżda essenzjalment, it-tqassim f'dan huwa 50% ta 'grad tiegħek 174 00:07:32,440 --> 00:07:34,530 se jkunu l-psets, li huwa sabiħ, għaliex dan huwa 175 00:07:34,530 --> 00:07:37,400 fejn int infiq l-kbira maġġoranza tal-kors ħin tiegħek fuq. 176 00:07:37,400 --> 00:07:39,854 Kwiżżijiet 40%, u tiegħek proġett finali se tkun ta '10%. 177 00:07:39,854 --> 00:07:42,520 Se jkun hemm żewġ kwizzijiet madwar Matul l-semestru. 178 00:07:42,520 --> 00:07:47,050 Naħseb li l-ħinijiet u d-dati huma wkoll elenkati fuq l-sillabu. 179 00:07:47,050 --> 00:07:49,210 >> Il-mod li aħna se jiġu gradazzjoni psets tiegħek 180 00:07:49,210 --> 00:07:53,930 hija li għandna essenzjalment erba valuri li aħna jassenjaw għal kull grad. 181 00:07:53,930 --> 00:07:57,250 Għandna valur ta 'ambitu, korrettezza, disinn, u stil. 182 00:07:57,250 --> 00:08:01,530 Allura kif tara, dan huwa tip ta 'tagħna formula għall-kalkolu psets. 183 00:08:01,530 --> 00:08:03,640 Tliet aħna nagħtu l-aktar piż li korrettezza, 184 00:08:03,640 --> 00:08:06,140 minħabba ovvjament coach tiegħek għandhom jiġu ittestjar għall-każijiet 185 00:08:06,140 --> 00:08:08,480 li irridu li jagħmel test għall. 186 00:08:08,480 --> 00:08:11,000 >> Inti guys kollha għandhom check50 għad-dispożizzjoni tiegħek. 187 00:08:11,000 --> 00:08:13,730 Huwa funzjoni utli ħafna li inti guys kollha jistgħu 188 00:08:13,730 --> 00:08:17,560 upload kodiċi tiegħek għal servers tagħna, fejn aħna ser jiċċekkja dan għalik. 189 00:08:17,560 --> 00:08:20,800 U inti stajt tidher dawk uċuħ frowny, smiley tiffaċċja. 190 00:08:20,800 --> 00:08:22,119 Huma qed verament, verament utli. 191 00:08:22,119 --> 00:08:23,910 Jekk jogħġbok ma jkun il- student li tixtieq tipprova 192 00:08:23,910 --> 00:08:26,230 li hardcode fil kollha tweġibiet għalihom. 193 00:08:26,230 --> 00:08:30,050 Stajt definitely raw pset fejn xi ħadd raw il-valuri kollha ta 'check50 194 00:08:30,050 --> 00:08:33,429 u huma biss hard kodifikati in-- jekk dan in-numru, jistampa dan in-numru. 195 00:08:33,429 --> 00:08:35,080 Jekk dan in-numru, jistampa dak in-numru. 196 00:08:35,080 --> 00:08:36,090 M'għandekx tagħmel dan. 197 00:08:36,090 --> 00:08:39,360 >> Anki jekk teknikament check50 hija korretta, 198 00:08:39,360 --> 00:08:41,809 tiegħek mod li ssolvi l- problema mhix korretta. 199 00:08:41,809 --> 00:08:45,770 Hekk biss użu check50 kemxejn. 200 00:08:45,770 --> 00:08:48,497 Iżda wkoll tagħmel ċert li inti jifhmu kif huwa funzjonament, 201 00:08:48,497 --> 00:08:50,580 il-programm qed jaħdem minbarra check50, 202 00:08:50,580 --> 00:08:53,120 għaliex ma nistgħux test kull każ possibbli ta 'check50. 203 00:08:53,120 --> 00:08:55,440 Aħna ser tkun ittestjar xi wħud minnhom. 204 00:08:55,440 --> 00:09:00,390 >> Disinn huwa essenzjalment kif mfassla tajjeb huwa kodiċi tiegħek? 205 00:09:00,390 --> 00:09:04,150 Jekk inti multipli kopja pasta linji ta 'kodiċi ħafna, ħafna drabi. 206 00:09:04,150 --> 00:09:06,960 Forsi inti ma għandekx pjuttost l-aħjar disinn fil-kodiċi tiegħek. 207 00:09:06,960 --> 00:09:09,470 Forsi wasal iż-żmien li jżidu li loop. 208 00:09:09,470 --> 00:09:12,090 Essenzjalment, hawnhekk huwa biss kollha dwar tipprova tagħmel kodiċi tiegħek, 209 00:09:12,090 --> 00:09:17,010 tipprova tikteb kodiċi tiegħek mod effiċjenti kemm jista 'jkun sabiex dak il-programm tiegħek runs 210 00:09:17,010 --> 00:09:19,630 malajr kemm jista 'jkun. 211 00:09:19,630 --> 00:09:20,996 >> Fl-aħħar nett, għandna stil. 212 00:09:20,996 --> 00:09:24,360 Allura istil huwa tip ta ' arbitrarja, terminu suġġettiv. 213 00:09:24,360 --> 00:09:27,470 I know we uffiċjalment għandna stil 50 gwida għall CS50, 214 00:09:27,470 --> 00:09:30,050 fejn hija jgħidlek, oh, inti għandu jkollhom spazju hawn. 215 00:09:30,050 --> 00:09:32,220 Għandek tip ta 'format kodiċi tiegħek b'dan il-mod. 216 00:09:32,220 --> 00:09:34,070 Għandek isem affarijiet b'dan il-mod. 217 00:09:34,070 --> 00:09:38,180 >> I ma verament kura, per se, kif inti tagħżel stil kodiċi tiegħek, 218 00:09:38,180 --> 00:09:39,840 biss sakemm inti toqgħod konsistenti. 219 00:09:39,840 --> 00:09:43,732 Per eżempju, jekk inti tixtieq li tħalli spazju wara erba tiegħek 220 00:09:43,732 --> 00:09:45,690 qabel erba loop tiegħek, biss tagħmel dan kull darba. 221 00:09:45,690 --> 00:09:46,523 M'għandekx tip ta 'tagħmel dan. 222 00:09:46,523 --> 00:09:47,730 M'għandekx tagħmel dan żminijiet oħra. 223 00:09:47,730 --> 00:09:51,046 Jekk inti tixtieq li żżomm kaboċċi ispazju braces b'ċertu mod, 224 00:09:51,046 --> 00:09:52,170 biss dejjem tagħmel dan il-mod. 225 00:09:52,170 --> 00:09:54,628 M'għandekx tip ta 'tagħmel dan x'imkien hawn u x'imkien ma jkunx hemm. 226 00:09:54,628 --> 00:09:57,010 Meta aħna qed gradazzjoni, huwa verament diffiċli 227 00:09:57,010 --> 00:09:59,420 jekk Għandi l-ebda idea kif int ifformattjar kodiċi tiegħek, 228 00:09:59,420 --> 00:10:02,064 affarijiet huma wacky u barra mill-post. 229 00:10:02,064 --> 00:10:04,980 Jekk inti biss iżommu konsistenti, huwa ħafna aktar faċli għalija bħala l-akbar 230 00:10:04,980 --> 00:10:06,310 li jkun kapaċi li jaqra kodiċi tiegħek. 231 00:10:06,310 --> 00:10:09,393 Huwa ħafna aktar faċli għalik bħala student li tkun kapaċi li tħares permezz kodiċi tiegħek 232 00:10:09,393 --> 00:10:11,720 u tara x'hemm ħażin ma dan mmejla għaliex hemm kwistjonijiet. 233 00:10:11,720 --> 00:10:15,740 Style hija waħda mill-affarijiet eħfef inti guys tista 'tagħmel biex tikseb punteġġi sħiħ. 234 00:10:15,740 --> 00:10:18,770 Essenzjalment, jekk inti biss kura, jekk inti tħallas ħames minuti ta 'attenzjoni 235 00:10:18,770 --> 00:10:22,760 kodiċi tiegħek kull ġimgħa, inti għandek tkun jkollna punti stil sħiħ. 236 00:10:22,760 --> 00:10:26,020 >> Fl-aħħar nett, għandna dak li sejjaħ l-multiplikatur ta 'ambitu. 237 00:10:26,020 --> 00:10:28,890 Scope-- Naf huwa a big kelma, speċjalment f'din il-klassi. 238 00:10:28,890 --> 00:10:31,030 Iżda ambitu, dak kollu li mezzi hija li int tipprova 239 00:10:31,030 --> 00:10:33,670 l psets għall-aħjar ħila tiegħek. 240 00:10:33,670 --> 00:10:37,180 Jekk iddawwar fi tlieta ta 'erba' problemi tiegħek 241 00:10:37,180 --> 00:10:39,460 u lanqas biss tipprova l aħħar wieħed, int probabilment 242 00:10:39,460 --> 00:10:41,630 ser jitilfu xi punti dwar l-ambitu. 243 00:10:41,630 --> 00:10:44,560 >> Anke jekk inti biss tibda l-problema, nagħmlu l-almu tiegħek biex jimxu permezz ta 'dan. 244 00:10:44,560 --> 00:10:47,691 Anki jekk din ma taħdimx, dawwar fi, minħabba li juri u juri 245 00:10:47,691 --> 00:10:50,190 lilna li inti qed tipprova, li inti attentat l-problema stabbilita 246 00:10:50,190 --> 00:10:51,430 għall-aħjar ħila tiegħek. 247 00:10:51,430 --> 00:10:53,800 U allura nistgħu nagħtuk punti sħaħ għall-iskop. 248 00:10:53,800 --> 00:10:58,715 >> Ambitu huwa wkoll importanti ħafna għal meta aħna jitkellmu dwar l-aktar baxx qatra punteġġ pset. 249 00:10:58,715 --> 00:11:02,010 Allura matul il-kors tal- semestru, inti guys jkollhom disa psets. 250 00:11:02,010 --> 00:11:05,340 U aħna fil-fatt se jkun twaqqa l-punteġġ aktar baxx minn dawk disa ', 251 00:11:05,340 --> 00:11:07,670 imma biss jekk ikollok sħiħa punti ambitu. 252 00:11:07,670 --> 00:11:11,120 >> Mela jekk inti mbagħad fi pset mhux kompluta, sfortunatament, ma nistgħux qatra li wieħed, 253 00:11:11,120 --> 00:11:13,540 għax l-ambitu tiegħek punti ma kinux tlestew. 254 00:11:13,540 --> 00:11:16,570 Għalhekk anki jekk inti għandek l-ġimgħa orribbli fejn int tmut u int marid 255 00:11:16,570 --> 00:11:20,040 jew kelb tiegħek imut, qattus tiegħek imut, u int mgħobbija żżejjed bil-homework, 256 00:11:20,040 --> 00:11:21,074 biss jippruvaw l pset. 257 00:11:21,074 --> 00:11:22,490 Jagħmlu dan għall-aħjar ħila tiegħek. 258 00:11:22,490 --> 00:11:23,840 Jekk ma jaħdimx, ma jimpurtax. 259 00:11:23,840 --> 00:11:24,506 Just dawwar in. 260 00:11:24,506 --> 00:11:26,590 Mill-inqas nistgħu nagħtu inti punti għall-isforz. 261 00:11:26,590 --> 00:11:28,510 >> A għall-isforz f'din il-klassi. 262 00:11:28,510 --> 00:11:30,170 Mill-inqas qatra punteġġ aktar baxx għall-isforz. 263 00:11:30,170 --> 00:11:32,354 So yeah. 264 00:11:32,354 --> 00:11:33,270 Li pretty ħafna dan. 265 00:11:33,270 --> 00:11:36,521 Ħadd ma jkollu mistoqsijiet hekk issa fuq kif aħna grad fil-klassi? 266 00:11:36,521 --> 00:11:37,187 Jew xi wieħed minn dawn? 267 00:11:37,187 --> 00:11:41,220 Kwalunkwe minn dawn l-hekk far-- sezzjonijiet, ħinijiet tal-uffiċċju? 268 00:11:41,220 --> 00:11:41,720 Kessaħ. 269 00:11:41,720 --> 00:11:46,720 270 00:11:46,720 --> 00:11:47,800 KOLLOX SEW. 271 00:11:47,800 --> 00:11:51,260 >> Allura dan huwa suġġett li ebda wieħed verament jħobb biex jitkellmu dwar. 272 00:11:51,260 --> 00:11:53,084 I ma verament jixtieq li jitkellmu dwar dan. 273 00:11:53,084 --> 00:11:55,250 You guys ma verament irridu biex tisma me jitkellmu dwar dan. 274 00:11:55,250 --> 00:11:57,690 Iżda sfortunatament, aħna kollha jkollhom biex jitkellmu dwar dan. 275 00:11:57,690 --> 00:12:00,110 David qatta '20 minuta lecture jitkellem dwar dan. 276 00:12:00,110 --> 00:12:02,580 U li huwa s-suġġett ta 'onestà akkademika. 277 00:12:02,580 --> 00:12:08,110 >> Allura aħna kollha hawn għandek probabbilment miktub l f'xi essay fil-karriera Yale tagħna. 278 00:12:08,110 --> 00:12:11,800 Imxejna probabbilment gotten talk fejn konna qallek li ma plagiarize essay tagħna, 279 00:12:11,800 --> 00:12:13,940 minħabba li x-xogħol huwa mhux tagħna. 280 00:12:13,940 --> 00:12:18,109 Fix-xjenza tal-kompjuter, għandna l-istess tip ta 'kunċett. 281 00:12:18,109 --> 00:12:20,150 Xogħol kollu li inti tissottometti, kollha kodiċi li tikteb 282 00:12:20,150 --> 00:12:21,900 għandu jkun kodiċi li ktibt. 283 00:12:21,900 --> 00:12:24,280 Jekk ma tkunx kodiċi li inti stajt kkupjati minn x'imkien ieħor. 284 00:12:24,280 --> 00:12:26,777 Jekk ma tkunx kodiċi li inti ħadthom Googled u plopped fil 285 00:12:26,777 --> 00:12:28,360 u inti ma verament jafu jekk xogħlijiet. 286 00:12:28,360 --> 00:12:32,440 Inti tip ta jkollhom sens ta ' dak li qed jagħmel iżda mhux verament. 287 00:12:32,440 --> 00:12:36,562 Meta fid-dubju, essenzjalment, huwa biss raġonevoli. 288 00:12:36,562 --> 00:12:38,520 Fuq sillabu tagħna, aħna għandna lista sħiħa ta 'affarijiet 289 00:12:38,520 --> 00:12:40,560 naraw bħala raġonevoli versus mhux raġonevoli. 290 00:12:40,560 --> 00:12:43,820 >> Per eżempju, raġonevoli huwa inti u ħabib tiegħek 291 00:12:43,820 --> 00:12:47,360 tiddiskuti dak li l-aħjar mod biex imorru dwar loġikament jsolvu problema. 292 00:12:47,360 --> 00:12:48,910 Li pjuttost raġonevoli. 293 00:12:48,910 --> 00:12:53,244 Dak li ma jkunx raġonevoli jekk inti guys ltqajna flimkien, ittajpjata-istess kodiċi, 294 00:12:53,244 --> 00:12:54,410 u kellu l-istess kodiċi. 295 00:12:54,410 --> 00:12:56,302 Li mhux raġonevoli. 296 00:12:56,302 --> 00:12:57,510 L-istess ħaġa, tip ta 'essay. 297 00:12:57,510 --> 00:12:59,290 Jekk inti tixtieq li tiddiskuti mal-ħabib tiegħek, ħej, 298 00:12:59,290 --> 00:13:00,220 dan huwa dak li nixtieq li jiktbu dwar. 299 00:13:00,220 --> 00:13:02,500 Dawn huma l-passi I jridu jieħdu biex tikteb dwar dan, kbir. 300 00:13:02,500 --> 00:13:03,208 Li isbaħ. 301 00:13:03,208 --> 00:13:04,790 Jekk jogħġbok jikkollaboraw ma 'xulxin. 302 00:13:04,790 --> 00:13:06,540 Jekk inti guys jibdew miktub l-istess ħaġa, 303 00:13:06,540 --> 00:13:10,020 dawwar fl-istess essay, li l-anqas OK. 304 00:13:10,020 --> 00:13:13,200 Allura meta fid-dubju, biss ma tagħmel dan. 305 00:13:13,200 --> 00:13:16,940 >> Hawnhekk, aħna fil CS50, għandna skripts li run biex awtomat li jittestjaw 306 00:13:16,940 --> 00:13:21,740 mhux biss il-korrettezza tal-kodiċi tiegħek, iżda wkoll l-uniċità tal-kodiċi tiegħek. 307 00:13:21,740 --> 00:13:25,920 Allura jekk jogħġbok ma tpoġġi magħna fil-pożizzjoni ta 'wara li jirreferu l-każ tiegħek għall EXCOMM. 308 00:13:25,920 --> 00:13:31,110 Jekk jogħġbok biss għal kulħadd, ejja biss jagħmlu dan esperjenza sabiħa. 309 00:13:31,110 --> 00:13:33,600 Kulħadd jitgħallem aħjar, aħna kollha huma kuntenti, 310 00:13:33,600 --> 00:13:37,926 u aħna huma kollha stabbiliti sa tirnexxi f'dan il-kors. 311 00:13:37,926 --> 00:13:39,800 Xi ħaġa li ħafna uniku dwar din il-klassi 312 00:13:39,800 --> 00:13:42,660 li naħseb kulħadd għandu verament tingħata attenzjoni għall hija li għandna 313 00:13:42,660 --> 00:13:44,930 dak li sejjaħ l dispjaċir klawsola fil sillabu tagħna. 314 00:13:44,930 --> 00:13:50,010 Allura essenzjalment, fi żmien 72 siegħa, jekk inti temmen li inti ghamilt xi ħaġa 315 00:13:50,010 --> 00:13:53,240 int ma tkunx ċert kien verament xieraq, jekk jogħġbok jiġu għandna. 316 00:13:53,240 --> 00:13:57,220 Aħna wegħda li fi żmien 72 siegħa aħna se tieħu ħsieb il-każ nfusna 317 00:13:57,220 --> 00:13:59,820 mingħajr ma jirreferi għal ogħla Awtorità fl-aministrazzjoni. 318 00:13:59,820 --> 00:14:03,100 >> Mela jekk inti come lili u jgħidu, Andi, ħej, jien verament sorry, 319 00:14:03,100 --> 00:14:07,620 iżda naħseb hemm linji koppja fil tiegħi kodiċi aħħar lejl li I tip ta 'Googled, 320 00:14:07,620 --> 00:14:10,120 ltqajna off ta 'munzell Overflow, kopja u pasted, 321 00:14:10,120 --> 00:14:13,680 u jien tassew, tassew sorry dwar dan, let me know. 322 00:14:13,680 --> 00:14:16,900 Jekk jogħġbok ma just let it Fester u ftit tama li I qabda. 323 00:14:16,900 --> 00:14:17,784 Aħna se qabda. 324 00:14:17,784 --> 00:14:18,450 Just come lili. 325 00:14:18,450 --> 00:14:20,520 Let me know fi żmien 72 siegħa. 326 00:14:20,520 --> 00:14:22,240 Aħna ser insemmu soluzzjoni. 327 00:14:22,240 --> 00:14:26,679 U aħna wegħda li aħna mhux se jirreferu għall awtoritajiet universitarji essenzjalment. 328 00:14:26,679 --> 00:14:29,220 Allura huwa fl-aħjar interess tiegħek biss tkun onest ma 'kulħadd 329 00:14:29,220 --> 00:14:31,720 involuti fil-kors. 330 00:14:31,720 --> 00:14:34,630 >> KOLLOX SEW. 331 00:14:34,630 --> 00:14:35,240 KOLLOX SEW. 332 00:14:35,240 --> 00:14:37,800 Allura issa, malajr qabel I jimxu fuq, ma xi ħadd 333 00:14:37,800 --> 00:14:42,670 jkollha mistoqsijiet dwar in loġistika dwar kif il-korsijiet aħna qed tmur jiddekorri, 334 00:14:42,670 --> 00:14:45,982 kif sezzjonijiet ser jiddekorri, xi li? 335 00:14:45,982 --> 00:14:46,711 KOLLOX SEW. 336 00:14:46,711 --> 00:14:47,210 Yeah. 337 00:14:47,210 --> 00:14:48,126 >> UDJENZA: [inaudible]? 338 00:14:48,126 --> 00:14:50,414 339 00:14:50,414 --> 00:14:51,080 ANDI Peng: Yeah. 340 00:14:51,080 --> 00:14:54,850 Allura quizzes-- kif ħafna minnkom huma fit-taqsima it-tnejn / l-Erbgħa? 341 00:14:54,850 --> 00:14:56,700 Kemm inti fil Tlieta / il-Ħamis? 342 00:14:56,700 --> 00:14:58,550 OK, dan huwa qasma solidu hawn. 343 00:14:58,550 --> 00:15:00,900 Allura l-mod li aħna run huwa fil-Yale hija li aħna 344 00:15:00,900 --> 00:15:04,040 se jkollhom żewġ separati quizzes-- wieħed għal kull section-- li 345 00:15:04,040 --> 00:15:06,160 ser jittieħdu matul il-klassi. 346 00:15:06,160 --> 00:15:09,310 Naħseb li huwa Ottubru, tmiem ta 'Ottubru, xi ħaġa bħal dik, bħala ġimgħa 347 00:15:09,310 --> 00:15:10,794 tal-kwizz. 348 00:15:10,794 --> 00:15:11,960 Yeah, hekk biss jaslu għal klassi. 349 00:15:11,960 --> 00:15:13,920 Fuq dik it-tnejn jew erbgħa inti ser tieħu l-kwizz. 350 00:15:13,920 --> 00:15:16,336 Fuq dik it-Tlieta u l-Ħamis, inti ser tieħu kwizz differenti. 351 00:15:16,336 --> 00:15:18,570 Iżda l-istess materjal se jkunu koperti. 352 00:15:18,570 --> 00:15:19,160 Yeah. 353 00:15:19,160 --> 00:15:20,660 Tajba kwistjoni. 354 00:15:20,660 --> 00:15:21,160 Yeah. 355 00:15:21,160 --> 00:15:23,260 >> UDJENZA: Fejn do we mur check gradi tagħna? 356 00:15:23,260 --> 00:15:23,926 >> ANDI Peng: Yeah. 357 00:15:23,926 --> 00:15:28,420 So I se tkun qed tibgħat out e-mail x'ikun kull ġimgħa 358 00:15:28,420 --> 00:15:31,460 meta kwizzijiet huma graded-- jew, sorry, meta psets huma ggradati. 359 00:15:31,460 --> 00:15:34,120 Psets huma normalment daru fi sa nofsinhar jew il-ġimgħa. 360 00:15:34,120 --> 00:15:37,540 So I wegħda li jiena ser tipprova tikseb minnhom lura lilek 361 00:15:37,540 --> 00:15:40,000 mill-nofsinhar tal-Ġimgħa wara. 362 00:15:40,000 --> 00:15:44,950 >> Kulmeta I grad a pset, I se tibgħat out notifika fuq il-ktieb grad 363 00:15:44,950 --> 00:15:47,070 li jgħidlek punteġġ tiegħek jistgħu jitqiesu online. 364 00:15:47,070 --> 00:15:52,022 Allura dritt din il-ġimgħa, wara I finitura gradazzjoni psets-ġimgħa li għaddiet, 365 00:15:52,022 --> 00:15:54,230 inti guys se tikseb e-mail notifika tghidlek, 366 00:15:54,230 --> 00:15:55,870 ħej dan huwa fejn inti mur għall-għan gradi tiegħek. 367 00:15:55,870 --> 00:15:57,680 U inti tista 'tara kull tqassim ta 'gradi tiegħek. 368 00:15:57,680 --> 00:15:58,555 Tista 'tara l-kummenti. 369 00:15:58,555 --> 00:16:00,360 Oh, ħaġa malajr ukoll. 370 00:16:00,360 --> 00:16:03,060 Is-sezzjoni kumment fil-kbira ktieb huwa fejn I ser probabbilment 371 00:16:03,060 --> 00:16:05,300 jonfqu l-maġġoranza tal gradazzjoni ħin tiegħi. 372 00:16:05,300 --> 00:16:07,094 Allura ħaġa waħda li verament importanti meta 373 00:16:07,094 --> 00:16:09,010 inti guys qed viewing gradi tiegħek fuq psets tiegħek 374 00:16:09,010 --> 00:16:11,400 mhux biss tfittex fil-punteġġ fiżiku 375 00:16:11,400 --> 00:16:14,630 iżda wkoll tieħu ħin biex verament taqra l-kummenti tiegħi. 376 00:16:14,630 --> 00:16:17,820 >> Spiss li jagħtik feedback dwar kif int jsolvu problema. 377 00:16:17,820 --> 00:16:20,480 Jekk għandek bżonn tagħmel xi ħaġa daqsxejn aħjar, 378 00:16:20,480 --> 00:16:24,080 kritika kostruttiva normalment ikun aħjar mogħtija f'dawk kummenti sezzjoni. 379 00:16:24,080 --> 00:16:26,950 Allura jekk jogħġbok, jekk jogħġbok, jien ser li jqattgħu ħin tikteb kummenti. 380 00:16:26,950 --> 00:16:30,440 Jekk jogħġbok, Nixtieq verament japprezzaw dan jekk inti guys jkun jaqra dawk il-kummenti. 381 00:16:30,440 --> 00:16:31,170 KOLLOX SEW. 382 00:16:31,170 --> 00:16:34,150 Kessaħ. 383 00:16:34,150 --> 00:16:34,680 >> Kull dritt. 384 00:16:34,680 --> 00:16:40,680 Allura aħna ser tibda titkellem u biss jirrevedu malajr 385 00:16:40,680 --> 00:16:45,040 xi wħud mill-materjal minn żero biss hekk aħna qed ġimgħa 386 00:16:45,040 --> 00:16:48,760 fuq il-paġna dritt għall bidu problemi-ġimgħa. 387 00:16:48,760 --> 00:16:52,600 Allura l-loop filwaqt hija waħda tat-tliet tipi ta 'linji 388 00:16:52,600 --> 00:16:54,510 aħna diskussa aktar kmieni f'din il-klassi. 389 00:16:54,510 --> 00:16:57,060 >> A loop filwaqt essenzjalment huwa miktub fil-sintassi 390 00:16:57,060 --> 00:17:00,666 fejn, filwaqt li ċerta kondizzjoni, tagħmel dan ripetutament, id-dritt? 391 00:17:00,666 --> 00:17:02,040 Jaħsbu li f'dan grafika hawn. 392 00:17:02,040 --> 00:17:04,780 Inti qed tmur biex tibda fi ċertu punt fiż-kodiċi tiegħek. 393 00:17:04,780 --> 00:17:09,030 Inti qed tmur biex jidħlu fil-kundizzjoni loop if-- I ma know-- x hija inqas minn wieħed. 394 00:17:09,030 --> 00:17:11,677 >> Jekk dan huwa minnu, int ser biex tesegwixxi l-korp loop. 395 00:17:11,677 --> 00:17:14,010 U int ser tkompli tagħmel li għal darb'oħra, għal darb'oħra, għal darb'oħra, 396 00:17:14,010 --> 00:17:17,900 aktar u over-- u huwa għalhekk huwa loop-- sakemm il-kundizzjoni tiegħek issir 397 00:17:17,900 --> 00:17:19,079 falza. 398 00:17:19,079 --> 00:17:22,140 Allura b'dan il-mod, linja filwaqt huwa wieħed mill-modi sempliċi 399 00:17:22,140 --> 00:17:25,619 jiktbu xi tip ta 'kundizzjoni li jeħtieġ li jirrepeti aktar u aktar u aktar. 400 00:17:25,619 --> 00:17:28,109 Just ikunu attenti meta int bil-miktub kwalunkwe tip ta 'linja 401 00:17:28,109 --> 00:17:32,140 li għandek kundizzjoni ħruġ kif ukoll aġġornament biex dak kollu li 402 00:17:32,140 --> 00:17:36,714 hu hekk li loop tiegħek ma biss run aktar u aktar infinitament. 403 00:17:36,714 --> 00:17:38,630 Fi kwalunkwe każ, int ser jixtiequ jagħmlu ċert 404 00:17:38,630 --> 00:17:42,670 li qed jinbidlu xi aspett ta ' kodiċi tiegħek jew fl-aħħar tal-linja 405 00:17:42,670 --> 00:17:46,680 biss biex tiżgura li inti għandek mod ta 'progress lejn l-kundizzjoni 406 00:17:46,680 --> 00:17:48,400 li inti tixtieq li jiltaqgħu sabiex aħħar. 407 00:17:48,400 --> 00:17:50,239 Does li jagħmel sens għal kulħadd? 408 00:17:50,239 --> 00:17:52,530 Aħna biss ma jridux li tkun maqbuda fil dan spirali fejn 409 00:17:52,530 --> 00:17:55,710 immorru madwar u madwar u hemm ebda mod biex jiksru l-linja. 410 00:17:55,710 --> 00:17:58,844 U kull loop essenzjalment għandu mod ta 'kif isir dan. 411 00:17:58,844 --> 00:17:59,344 KOLLOX SEW. 412 00:17:59,344 --> 00:18:03,030 413 00:18:03,030 --> 00:18:06,060 >> It-tieni nett, ħafna minnkom fil psets Mario tiegħek 414 00:18:06,060 --> 00:18:08,910 probabbilment kellha timpjega dan it-tip ta 'loop. 415 00:18:08,910 --> 00:18:11,802 Huwa msejjaħ do filwaqt loop. 416 00:18:11,802 --> 00:18:14,510 L-ewwelnett, jista 'xi ħadd tell me x'inhi d-differenza bejn do 417 00:18:14,510 --> 00:18:16,586 filwaqt loop u loop filwaqt hu? 418 00:18:16,586 --> 00:18:17,086 Yeah. 419 00:18:17,086 --> 00:18:21,030 >> UDJENZA: Il-do filwaqt loop hija ta 'l-ewwel [inaudible]. 420 00:18:21,030 --> 00:18:22,120 >> ANDI Peng: Yeah, eżattament. 421 00:18:22,120 --> 00:18:27,130 Allura do filwaqt loop dejjem ma dak kollu hu ġewwa l-do, ġewwa l-parentesi 422 00:18:27,130 --> 00:18:30,520 hemm u ma din il-kundizzjoni qabel verifika għall the-- sorry, 423 00:18:30,520 --> 00:18:32,940 ma dan il-kodiċi qabel verifika għall-kundizzjoni. 424 00:18:32,940 --> 00:18:37,200 U dan huwa speċjalment rilevanti lilna hawn f'din il-klassi, minħabba li ħafna drabi 425 00:18:37,200 --> 00:18:41,450 aħna qed tmur jridu pront l-utent għal xi tip ta 'input. 426 00:18:41,450 --> 00:18:43,520 U mbagħad, jiddependi fuq l-input li tagħtina, 427 00:18:43,520 --> 00:18:46,150 imbagħad inkunu nistgħu tevalwa, oh, do għandna bżonn li twassalhom mill-ġdid? 428 00:18:46,150 --> 00:18:49,930 >> Allura fil Mario, jekk l-utent ħadt għoli negattiv, per eżempju, 429 00:18:49,930 --> 00:18:52,990 int ser ewwel pront u jagħmlu dak kollu li huwa ġewwa. 430 00:18:52,990 --> 00:18:54,820 Imbagħad int ser jiċċekkja waqt. 431 00:18:54,820 --> 00:18:57,570 You know, huwa negattiv 1, huwa li numru pożittiv? 432 00:18:57,570 --> 00:19:00,680 Jekk mhuwiex, jien ser imorru lura u rrepeti l-do u rrepeti 433 00:19:00,680 --> 00:19:03,950 u ripetuta u rrepeti sakemm finalment jagħtuk numru li tixtieq, 434 00:19:03,950 --> 00:19:07,002 li aħna kollha jistgħu jimpjegaw fil-kodiċi tagħna. 435 00:19:07,002 --> 00:19:09,210 Huwa pretty importanti għall essenzjalment kwalunkwe input utent. 436 00:19:09,210 --> 00:19:11,760 I jistgħu jiggarantixxu inti xi darba fi pset fejn 437 00:19:11,760 --> 00:19:15,070 aħna nitolbuk input kwalunkwe tip ta 'kodiċi, aħna qed 438 00:19:15,070 --> 00:19:17,540 probabbilment ser jagħtuk każ ta 'prova li aħna qed 439 00:19:17,540 --> 00:19:21,200 ser jagħtuk xi ħaġa ħażina li l- ser jippruvaw jiksru kodiċi tiegħek. 440 00:19:21,200 --> 00:19:25,044 >> Jekk nippruvaw nitolbuk għal input numru sħiħ, nistgħu biss jagħtik string 441 00:19:25,044 --> 00:19:26,460 u tara kif tieħu ħsieb dan. 442 00:19:26,460 --> 00:19:30,610 Jekk aħna nitolbuk li jimpjegaw età, aħna jistgħu jagħtuk numru negattiv 443 00:19:30,610 --> 00:19:32,340 biex tara kif inti tieħu ħsieb li. 444 00:19:32,340 --> 00:19:37,260 Just kun żgur li inti guys qed jittestjaw għal każijiet fejn inti ma tikseb l-aħjar 445 00:19:37,260 --> 00:19:38,590 input, ejja biss jgħidu. 446 00:19:38,590 --> 00:19:40,510 U do filwaqt loop huwa oftentimes l-aħjar 447 00:19:40,510 --> 00:19:45,260 mod biex disinn kodiċi tiegħek sabiex li jissodisfa dak l-ambitu. 448 00:19:45,260 --> 00:19:45,760 KOLLOX SEW. 449 00:19:45,760 --> 00:19:48,930 450 00:19:48,930 --> 00:19:49,470 >> KOLLOX SEW. 451 00:19:49,470 --> 00:19:53,270 Allura dan huwa probabbilment l-aktar loop kumpless barra mit-tliet 452 00:19:53,270 --> 00:19:54,990 li konna ħares lejn s'issa. 453 00:19:54,990 --> 00:19:56,689 U jidher ħafna scary fl-ewwel. 454 00:19:56,689 --> 00:19:59,730 Imma I garanzija li inti, ladarba inti guys tikseb l-hang kif tuża għall loop, 455 00:19:59,730 --> 00:20:03,320 huwa wieħed mill-aktar affarijiet utli, għodod aktar utli fil-armament tiegħek 456 00:20:03,320 --> 00:20:05,300 biex isir progress f'din il-klassi. 457 00:20:05,300 --> 00:20:09,920 >> Hekk per eżempju, fil Scratch, kellna dan il-blokk sempliċi ħafna 458 00:20:09,920 --> 00:20:13,180 li biss qal irrepeti dan ċerta frażijiet Ċertu numru ta 'drabi. 459 00:20:13,180 --> 00:20:16,260 Mill-mod, SAJ-- dan huwa Scaz Andi Jason. 460 00:20:16,260 --> 00:20:18,740 Aħna oftentimes jiffirmaw emails SAJ tagħna. 461 00:20:18,740 --> 00:20:20,360 Jekk aħna ngħidu SAJ, ma jkun konfuż. 462 00:20:20,360 --> 00:20:22,630 Li jinsab biss us. 463 00:20:22,630 --> 00:20:28,600 >> Allura fil Scratch, konna kapaċi li jkollhom blokk li qal, irrepeti I love SAJ! 464 00:20:28,600 --> 00:20:29,430 10 darbiet. 465 00:20:29,430 --> 00:20:30,130 Sempliċi ħafna. 466 00:20:30,130 --> 00:20:32,302 Il-loġika wara li hija ħafna, sempliċi ħafna, id-dritt? 467 00:20:32,302 --> 00:20:35,260 Irrid ewwel jgħaddu mill-ewwel ħin u tara li, it-tieni darba 468 00:20:35,260 --> 00:20:38,510 u tara li, tielet darba, oħrajn u l-bqija, sakemm inti hit sa 10. 469 00:20:38,510 --> 00:20:41,960 >> U l-mod aħna se jirrappreżenta dak fil kodiċi huwa biss permezz ta 'sempliċi għall loop. 470 00:20:41,960 --> 00:20:45,440 Allura għal, int ser tiddikjara varjabbli tiegħek hawn, f'dan il-każ, 471 00:20:45,440 --> 00:20:46,349 ma 'int. 472 00:20:46,349 --> 00:20:47,390 Aħna qed tmur biex isem li bih i. 473 00:20:47,390 --> 00:20:49,500 Aħna qed tmur biex initialize dan għal 0. 474 00:20:49,500 --> 00:20:52,490 U l-edizzjoni waqfien hija se tkun i huwa inqas minn 10. 475 00:20:52,490 --> 00:20:54,622 U l-aġġornament se tkun i ++. 476 00:20:54,622 --> 00:20:57,750 >> U fil-loop, li għaddej li jiġi eżegwit sakemm eventwalment 477 00:20:57,750 --> 00:21:01,490 hits-aħħar tal-condition-- li fih każ, li għaddej biex jiksru l-linja. 478 00:21:01,490 --> 00:21:04,600 Għandu jkun hemm Jittieħed li inti guys kull tip ta 'osservata qabel 479 00:21:04,600 --> 00:21:07,270 u kellha tagħmel għall-problema tiegħek sett wieħed. 480 00:21:07,270 --> 00:21:12,310 Ħadd ma jkollu xi mistoqsijiet dwar għal-linji dritt issa? 481 00:21:12,310 --> 00:21:12,930 KOLLOX SEW. 482 00:21:12,930 --> 00:21:13,430 Great. 483 00:21:13,430 --> 00:21:17,520 484 00:21:17,520 --> 00:21:18,620 >> KOLLOX SEW. 485 00:21:18,620 --> 00:21:22,270 Għalhekk għal dawk fostkom li għadhom aqra l-spec pset għal din il-ġimgħa 486 00:21:22,270 --> 00:21:27,690 jafu li aħna ser ikollhom jimpjegaw xi ħaġa imsejħa ASCII u tabella ASCII. 487 00:21:27,690 --> 00:21:32,380 Allura David fil lecture marru fuq fil-qosor kif il-kompjuters essentially-- kollox 488 00:21:32,380 --> 00:21:35,410 hija kodifikata fil-kompjuter fil binarju, fil żerijiet u dawk. 489 00:21:35,410 --> 00:21:39,740 U l-mod li l-kompjuters huma kapaċi li jaħżen valuri differenti flimkien 490 00:21:39,740 --> 00:21:44,360 li żerijiet u dawk huma permezz mapping dawn in-numri li jirrappreżentaw ċifri oħra 491 00:21:44,360 --> 00:21:47,220 jew karattri essenzjalment oħra. 492 00:21:47,220 --> 00:21:49,810 >> Allura f'dan il-każ, ASCII table-- dan kollu ma 493 00:21:49,810 --> 00:21:53,600 huwa karattri mappa, jew Chars, għal numri. 494 00:21:53,600 --> 00:21:57,385 Allura l-fajl source code tiegħek computer-- jara, 495 00:21:57,385 --> 00:22:00,010 ħej, mazz ta 'żerijiet u dawk, żerijiet u dawk, żerijiet u dawk. 496 00:22:00,010 --> 00:22:02,350 Dak hu maħżun fil- memorja attwali tal-kompjuter tiegħek. 497 00:22:02,350 --> 00:22:04,750 >> Imma meta aħna bnedmin jridu jikkomunikaw mal-kompjuter, 498 00:22:04,750 --> 00:22:08,249 aħna want-- ngħidu, per eżempju, jekk irrid il uppercase A, 499 00:22:08,249 --> 00:22:10,540 Jien ser jeħtieġu xi mod tal javżak il-kompjuter, oh, 500 00:22:10,540 --> 00:22:16,300 meta I tip uppercase A, I tfisser din ir-rappreżentanza fil binarja. 501 00:22:16,300 --> 00:22:22,260 >> U għalhekk l-mod kif nagħmlu dan hu threw Ħaġa arbitrarja imsejħa tabella ASCII, 502 00:22:22,260 --> 00:22:25,020 fejn aħna, bħala bnedmin, kif programmaturi, xi żmien ilu, 503 00:22:25,020 --> 00:22:28,660 aħna arbitrarju iddeċieda li aħna kienu ser tassenja dawn numru 504 00:22:28,660 --> 00:22:30,960 Valuri għal dawn il-karattri. 505 00:22:30,960 --> 00:22:32,720 >> Allura inti guys tista google dan online. 506 00:22:32,720 --> 00:22:37,120 Naħseb li hemm rabta lilha tiegħek pset-- biss tabella mappa ASCII, ASCII 507 00:22:37,120 --> 00:22:37,720 tabella. 508 00:22:37,720 --> 00:22:40,722 Hija biss jittraduċi binarja numri fis karattri. 509 00:22:40,722 --> 00:22:42,930 U li għaddej biex tkun ferm utli għall tiegħek sett problema 510 00:22:42,930 --> 00:22:45,470 kull meta inti tixtieq li jikkalkula xejn jew jekk inti 511 00:22:45,470 --> 00:22:47,880 jridu juru ċerti karattri jew interi 512 00:22:47,880 --> 00:22:50,327 jew jimmanipulaw ċerti karattri. 513 00:22:50,327 --> 00:22:52,160 Li għaddej biex tkun ferm importanti li intom kollha 514 00:22:52,160 --> 00:22:55,140 taf kif jinnaviga tabella ASCII. 515 00:22:55,140 --> 00:23:01,260 >> Hekk per eżempju, il-uppercase A huwa rappreżentat min-numru 65. 516 00:23:01,260 --> 00:23:04,207 U l zghar a hija rappreżentata minn 97. 517 00:23:04,207 --> 00:23:07,040 Allura huwa importanti li tkun taf li l- differenza bejn iż-żewġ valuri 518 00:23:07,040 --> 00:23:08,320 huwa 32. 519 00:23:08,320 --> 00:23:13,210 Oftentimes, jekk ikollok bżonn li wieħed jaqleb minn waħda għall-oħra, id-differenza hija ta '32. 520 00:23:13,210 --> 00:23:15,710 U tinkwetax jekk int xorta ta 'konfuż fuq dan fl-ewwel. 521 00:23:15,710 --> 00:23:20,230 Aħna ser imorru fuq kif nixtiequ jimpjegaw dan fil-kodiċi attwali. 522 00:23:20,230 --> 00:23:24,700 523 00:23:24,700 --> 00:23:26,380 >> KOLLOX SEW. 524 00:23:26,380 --> 00:23:30,770 Għalhekk għal dawk tal inti ma 'laptops out, tħossok liberu li pull up tabella ASCII, 525 00:23:30,770 --> 00:23:36,030 minħabba li dawn se probabbilment jeħtieġu li inti guys biex referenza 526 00:23:36,030 --> 00:23:38,100 dak li l-karattri huma. 527 00:23:38,100 --> 00:23:38,640 KOLLOX SEW. 528 00:23:38,640 --> 00:23:42,840 >> Sabiex tkun taf li ċerti karattri mappa biex ċerti numri, 529 00:23:42,840 --> 00:23:47,240 jekk I kellhom imexxu biss l-ewwel linja ta 'dik code-- l printf a, 530 00:23:47,240 --> 00:23:50,900 zghar a, nieqes uppercase A. Hawn xi ħadd 531 00:23:50,900 --> 00:23:55,880 jkollhom raden fuq dak li jkun stampar ta 'l-iskrin dritt issa? 532 00:23:55,880 --> 00:23:58,190 >> Allura l-ewwel nett, dak li ma zghar a jirrappreżenta? 533 00:23:58,190 --> 00:24:00,990 Liema numru huwa li kodifikati fit-tabella ASCII. 534 00:24:00,990 --> 00:24:01,490 Jiddispjacini? 535 00:24:01,490 --> 00:24:02,630 >> UDJENZA: 97? 536 00:24:02,630 --> 00:24:03,630 >> ANDI Peng: 97, kbir. 537 00:24:03,630 --> 00:24:05,077 U dak li huwa uppercase A? 538 00:24:05,077 --> 00:24:06,330 >> UDJENZA: 65. 539 00:24:06,330 --> 00:24:08,255 >> ANDI Peng: Allura x'inhi 97 minus 65? 540 00:24:08,255 --> 00:24:09,227 >> UDJENZA: 32. 541 00:24:09,227 --> 00:24:09,810 ANDI Peng: OK. 542 00:24:09,810 --> 00:24:13,530 Allura dak li inti guys think se jiġri meta I input dik il-linja tal-kodiċi 543 00:24:13,530 --> 00:24:14,670 fis-kompjuter tiegħi? 544 00:24:14,670 --> 00:24:17,981 545 00:24:17,981 --> 00:24:19,896 >> UDJENZA: [inaudible]. 546 00:24:19,896 --> 00:24:21,020 ANDI Peng: Jiddispjacini, jitkellmu up. 547 00:24:21,020 --> 00:24:22,520 Tinkwetax. 548 00:24:22,520 --> 00:24:25,750 Dan huwa sikur ħafna ambjent, nieqes l-camera. 549 00:24:25,750 --> 00:24:27,550 Aħna kollha jmorru to-- ebda inkwiet. 550 00:24:27,550 --> 00:24:30,940 Just aħna qed kollha ser nippretendu simili huwa biss us tkessiħ f'din il-kamra. 551 00:24:30,940 --> 00:24:31,480 Tinkwetax. 552 00:24:31,480 --> 00:24:33,410 Nru kwistjoni hija wisq stupid. 553 00:24:33,410 --> 00:24:35,300 Ebda tweġiba hija risposta stupid. 554 00:24:35,300 --> 00:24:38,260 Jien probabbilment se jagħmlu żbalji fil-kors ta 'tagħlim tiegħi. 555 00:24:38,260 --> 00:24:40,740 Serjament, guys, biss blurt out. 556 00:24:40,740 --> 00:24:43,092 Ikunu kunfidenti fl-yourself, inti taf? 557 00:24:43,092 --> 00:24:43,800 Allura dak li kien li? 558 00:24:43,800 --> 00:24:47,990 Min qal li l-aħħar risposta? 559 00:24:47,990 --> 00:24:48,540 KOLLOX SEW. 560 00:24:48,540 --> 00:24:50,380 Jgħajtu li sbieħ u ċara. 561 00:24:50,380 --> 00:24:51,220 >> UDJENZA: 32? 562 00:24:51,220 --> 00:24:51,850 >> ANDI Peng: 32. 563 00:24:51,850 --> 00:24:54,141 OK, ejja jimxu dan il-kodiċi u tara jekk dan huwa dak li jiġri. 564 00:24:54,141 --> 00:25:00,260 565 00:25:00,260 --> 00:25:00,760 KOLLOX SEW. 566 00:25:00,760 --> 00:25:03,300 567 00:25:03,300 --> 00:25:06,360 Allura kif inti guys tista tip ta ' tara, in-notazzjoni tipiċi stajt 568 00:25:06,360 --> 00:25:12,250 twaqqaf hawn għal kif aħna se jimpjegaw kwalunkwe tip ta 'programm fil-kompjuter tagħna. 569 00:25:12,250 --> 00:25:14,770 Għandna funzjoni ewlenija tagħna fi ħdan funzjoni prinċipali tagħna. 570 00:25:14,770 --> 00:25:17,265 Jien biss ser kopja u paste din il-linja tal-kodiċi. 571 00:25:17,265 --> 00:25:21,082 572 00:25:21,082 --> 00:25:23,540 Ukoll ikunu attenti meta inti guys l-ikkupjar u pasta kodiċi. 573 00:25:23,540 --> 00:25:28,750 Kultant ċerti operaturi ma paste fuq korrett. 574 00:25:28,750 --> 00:25:31,397 F'dak il-każ, l minus sinjal kien effettivament sing. 575 00:25:31,397 --> 00:25:32,980 U għalhekk l-kompjuter ma pick it up. 576 00:25:32,980 --> 00:25:35,870 So I kellha tmur lura u fiżikament retype dik. 577 00:25:35,870 --> 00:25:37,846 Just ikunu attenti meta inti guys qed jagħmlu dan. 578 00:25:37,846 --> 00:25:41,178 579 00:25:41,178 --> 00:25:42,660 >> KOLLOX SEW. 580 00:25:42,660 --> 00:25:43,980 Aħna qed tmur biex imexxu dan hawn. 581 00:25:43,980 --> 00:25:45,670 Allura aħna qed tmur biex cd fis section2 tagħna. 582 00:25:45,670 --> 00:25:50,470 583 00:25:50,470 --> 00:25:52,030 Stajt sejjaħ dan asciimath programm. 584 00:25:52,030 --> 00:25:55,690 Mela ftakar, meta we run xi programm, irridu l-ewwel josservawha 585 00:25:55,690 --> 00:25:57,150 billi running permezz jagħmlu tagħna. 586 00:25:57,150 --> 00:26:00,030 U allura aħna rridu li tmexxi effettivament il-programm billi tagħmel dot slash. 587 00:26:00,030 --> 00:26:01,280 Allura aħna qed tmur biex ./asciimath. 588 00:26:01,280 --> 00:26:05,780 589 00:26:05,780 --> 00:26:06,590 >> Dritt, hemm immorru. 590 00:26:06,590 --> 00:26:07,410 U naraw 32. 591 00:26:07,410 --> 00:26:07,930 Prosit. 592 00:26:07,930 --> 00:26:10,340 You jistħoqqilhom biċċa ta 'kandju. 593 00:26:10,340 --> 00:26:11,160 Candy għalik. 594 00:26:11,160 --> 00:26:11,900 Jiddispjacini. 595 00:26:11,900 --> 00:26:13,100 Kull dritt. 596 00:26:13,100 --> 00:26:13,670 KOLLOX SEW. 597 00:26:13,670 --> 00:26:18,070 Allura nistgħu mmorru lura għall-eżempju tagħna hawn. 598 00:26:18,070 --> 00:26:23,530 599 00:26:23,530 --> 00:26:24,345 Aah, l-ebda. 600 00:26:24,345 --> 00:26:29,147 601 00:26:29,147 --> 00:26:31,090 Aah. 602 00:26:31,090 --> 00:26:32,490 KOLLOX SEW. 603 00:26:32,490 --> 00:26:34,610 Jien biss se jżommha bħal dik. 604 00:26:34,610 --> 00:26:48,520 605 00:26:48,520 --> 00:26:51,240 KOLLOX SEW. 606 00:26:51,240 --> 00:26:51,740 KOLLOX SEW. 607 00:26:51,740 --> 00:26:55,340 Allura kif inti guys tista 'tara, nistgħu nagħmlu lottijiet ta 'affarijiet interessanti ħafna, 608 00:26:55,340 --> 00:26:58,880 ħafna affarijiet ħafna jibred, lott ta ' affarijiet kumplikati ħafna li jinvolvu 609 00:26:58,880 --> 00:27:02,720 Karattri ASCII u numri. 610 00:27:02,720 --> 00:27:05,890 Ladarba inti tibda l-linja ħames, li l-lott biex isegwu flimkien. 611 00:27:05,890 --> 00:27:07,640 Aħna mhux se jmorru permezz tas-sezzjoni. 612 00:27:07,640 --> 00:27:10,720 Ħossok liberu li, jekk inti tista ', Raġuni fuq karta 613 00:27:10,720 --> 00:27:14,750 ewwel dwar dak li għandu jiġri meta inti input sensiela bħal ta 'valuri. 614 00:27:14,750 --> 00:27:19,720 Per eżempju, f'dak aħħar linja, għandna z-- li jirrappreżenta number-- ċerta 615 00:27:19,720 --> 00:27:24,740 a-- li jirrappreżenta wkoll ċerti number-- plus 1 modulos 26 616 00:27:24,740 --> 00:27:26,750 plus zghar a. 617 00:27:26,750 --> 00:27:29,220 >> Jekk inti guys iżommu qari permezz ta 'dawn, inti 618 00:27:29,220 --> 00:27:34,009 tista 'tara mudell toħroġ fil kif aħna qed titħaddem il-kodiċi. 619 00:27:34,009 --> 00:27:36,050 I ħafna, jissuġġerixxu ħafna wara taqsima lilkom kollha 620 00:27:36,050 --> 00:27:38,160 guys jimxi 'l quddiem u l-input dawk kollha fil-kompjuter tiegħek 621 00:27:38,160 --> 00:27:40,060 u tara x'tip ta ' numri huma joħorġu 622 00:27:40,060 --> 00:27:43,090 u raġunament permezz għaliex dawn huma jiġri, għaliex għal psets tiegħek 623 00:27:43,090 --> 00:27:45,060 dan ser ikun tassew importanti għalik biex tifhem 624 00:27:45,060 --> 00:27:47,132 għaliex ċerti affarijiet qed jiġri. 625 00:27:47,132 --> 00:27:48,590 Kollha ta 'dawn slides se jkun online. 626 00:27:48,590 --> 00:27:51,510 Sabiex l-ebda inkwiet dwar jippruvaw fiżikament kopja noti. 627 00:27:51,510 --> 00:27:52,510 Online Kollox s. 628 00:27:52,510 --> 00:27:54,050 Din it-taqsima stess tkun online. 629 00:27:54,050 --> 00:27:57,500 Kollha source code tiegħi li Niġri se jkun online. 630 00:27:57,500 --> 00:27:58,180 Yeah. 631 00:27:58,180 --> 00:27:59,430 Did inti għad għandek xi mistoqsija? 632 00:27:59,430 --> 00:28:00,587 UDJENZA: X'inhu modulos? 633 00:28:00,587 --> 00:28:01,170 ANDI Peng: OK. 634 00:28:01,170 --> 00:28:05,620 Allura modulo hija operatur li għaddej biex jkun pjuttost importanti li pset guys tiegħek 635 00:28:05,620 --> 00:28:06,690 hawn. 636 00:28:06,690 --> 00:28:12,280 Allura l-mod li l-operaturi fis-C u fix-xogħol ta 'programmar 637 00:28:12,280 --> 00:28:16,360 huwa li inti għandek dak li sejjaħ l- simbolu diviżjoni u s-simbolu modulus, 638 00:28:16,360 --> 00:28:18,350 li huwa bħad-sinjal fil-mija. 639 00:28:18,350 --> 00:28:24,840 >> Għalhekk fl C, meta inti tagħmel integer diviż bl integer ma slash, 640 00:28:24,840 --> 00:28:27,720 C għandu tendenza li tixtieq li tnaqqas off kollha tal-punti deċimali, 641 00:28:27,720 --> 00:28:30,290 minħabba integer trid li jikkonvertu għal numru sħiħ. 642 00:28:30,290 --> 00:28:33,550 Huwa mhux ser tixtieq li tkun doppju bil-mazz ta 'deċimali kollu wara dan. 643 00:28:33,550 --> 00:28:39,322 >> Hekk jekk nagħmel 3 diviż bi 2, li għaddej biex jinqata 'l-0.5 u biss jagħtuk 1. 644 00:28:39,322 --> 00:28:41,530 Allura li xi ħaġa li tkun attenti ħafna ta 'meta int 645 00:28:41,530 --> 00:28:45,294 tagħmel xi tip ta 'matematika fl-ipprogrammar, hija li n-numri ikollok 646 00:28:45,294 --> 00:28:47,210 ma jistgħux ikunu n-numri li inti kienu qed jaħsbu, 647 00:28:47,210 --> 00:28:50,190 u huwa għalhekk arrotondament fil tiegħek aħħar pset huwa tant importanti. 648 00:28:50,190 --> 00:28:51,980 >> Modulo jagħtik l-bqija. 649 00:28:51,980 --> 00:28:56,200 Għalhekk, per eżempju, jekk I ma 3 modulo 2-- hekk 3 fil-mija sinjal 2-- 650 00:28:56,200 --> 00:28:58,020 dan jagħti inti l-bqija ta 'dan. 651 00:28:58,020 --> 00:29:00,460 Allura 3 diviża bi 2 huwa 1.5. 652 00:29:00,460 --> 00:29:01,410 Li għamilhom 1 bqija tal-1. 653 00:29:01,410 --> 00:29:04,600 Ikun jagħtuk l-1, li hija l-bqija ta 'dik. 654 00:29:04,600 --> 00:29:07,361 >> Allura meta inti guys qed jiċċaqalqu tul il-mejda ASCII, 655 00:29:07,361 --> 00:29:09,735 modulo se jispiċċa jkun xi ħaġa li l-importanti ħafna, 656 00:29:09,735 --> 00:29:11,240 u aħna ser jiddiskutu li aktar tard. 657 00:29:11,240 --> 00:29:17,750 658 00:29:17,750 --> 00:29:19,040 >> KOLLOX SEW. 659 00:29:19,040 --> 00:29:27,300 Allura xi ħaġa li hija pjuttost, pretty ġodda u pretty unika 660 00:29:27,300 --> 00:29:31,920 li konna diskussi din il-ġimgħa qed il-kunċett ta 'dak li firxa hija. 661 00:29:31,920 --> 00:29:34,370 Allura firxa hija l-ewwel tip ta 'struttura data 662 00:29:34,370 --> 00:29:36,320 li aħna qed tmur biex jiltaqgħu f'din il-klassi. 663 00:29:36,320 --> 00:29:40,010 Kollha istruttura tad-data hija hija xi tip ta 'arbitrarja, 664 00:29:40,010 --> 00:29:43,370 litteralment affarijiet simili istruttura li aħna bħala programmaturi ħolqu, 665 00:29:43,370 --> 00:29:47,890 li konna jitqiegħdu fil-kodiċi tagħna li jista 'jkun fihom biċċiet oħra ta' kodiċi. 666 00:29:47,890 --> 00:29:51,090 >> Allura f'dan is-sens, l-array-- jaħsbu li bħala kabinett fajl, 667 00:29:51,090 --> 00:29:53,470 fejn jekk inti tiftaħ differenti ixkafef tal-kabinett fajl tiegħek, 668 00:29:53,470 --> 00:29:55,630 inti tista 'aċċess affarijiet differenti. 669 00:29:55,630 --> 00:29:58,630 Fil-memorja, firxa hija biss tagħmel l-istess ħaġa fuq il-kompjuter tiegħek. 670 00:29:58,630 --> 00:30:01,730 Inti jista 'jkollhom differenti blocks-- aħna jsejħulhom indices-- ta 'firxa. 671 00:30:01,730 --> 00:30:04,210 Huwa biss bħal blokk, xkaffa ta 'memorja 672 00:30:04,210 --> 00:30:07,580 li konna maħluqa fi ħdan tiegħek kompjuter li inti tista 'input 673 00:30:07,580 --> 00:30:10,270 ċerti affarijiet fl-ispazji differenti. 674 00:30:10,270 --> 00:30:18,000 >> Allura ma 'firxa, inti dejjem għandhom specify-- 675 00:30:18,000 --> 00:30:22,360 għandek tispeċifika li tkun iddikjarat li firxa fil-format li ġej. 676 00:30:22,360 --> 00:30:24,290 Int ser ewwel ispeċifika t-tip tad-data 677 00:30:24,290 --> 00:30:25,831 li tixtieq toħloq mill-firxa. 678 00:30:25,831 --> 00:30:28,870 Jekk irrid firxa ta 'numri interi, I se timplimenta int hemm dritt. 679 00:30:28,870 --> 00:30:32,079 Jekk irrid firxa ta 'kordi, Jien ser tpoġġi kordi hemmhekk, 680 00:30:32,079 --> 00:30:34,995 l-isem ta 'firxa tiegħek, u mbagħad int se jkollhom parentesi kwadri. 681 00:30:34,995 --> 00:30:39,580 U ġewwa il-parentesi kwadri, int ser ikollhom id-daqs ta 'firxa tiegħek. 682 00:30:39,580 --> 00:30:42,900 >> Xi ħaġa li verament importanti li wieħed iżomm f'moħħu meta jinħoloq arrays hija 683 00:30:42,900 --> 00:30:46,530 li, ladarba inti toħloq firxa, li d-daqs ma jistax jinbidel. 684 00:30:46,530 --> 00:30:50,180 Mela jekk inti taf dak id-dritt issa għandek firxa ta 'daqs 10, 685 00:30:50,180 --> 00:30:54,550 inti taf li jien ser ikollhom 10 ċelluli ġewwa jew 10 indiċijiet fi ħdan dan array, 686 00:30:54,550 --> 00:30:56,830 u huwa qatt ser biex jespandu jew inaqqsu 687 00:30:56,830 --> 00:30:59,850 x'ikun, u li hemm bħalissa biss 10 blokki ta 'spazju 688 00:30:59,850 --> 00:31:04,490 allokati fil-memorja tiegħek li jista 'jaħżen sa 10 affarijiet ta 'kwalunkwe inti ħadthom tpoġġi. 689 00:31:04,490 --> 00:31:08,790 >> Allura b'dan il-mod, tip data array, l-istruttura data li hija firxa 690 00:31:08,790 --> 00:31:13,392 hija differenti ħafna minn xi oħrajn Aħna ser tkun tkopri aktar tard f'dan il-kors. 691 00:31:13,392 --> 00:31:15,170 Yeah. 692 00:31:15,170 --> 00:31:20,080 Per eżempju, jekk int riedu joħolqu firxa ta 'daqs 3 li 693 00:31:20,080 --> 00:31:23,670 varjabbli magħluq tal integer-- oh, sorry, ta temperature-- 694 00:31:23,670 --> 00:31:25,640 u t-temperatura, tal Naturalment, huwa integer. 695 00:31:25,640 --> 00:31:28,710 >> Allura aħna se toħloq int, li hija l- tip ta 'data ta' dak li rridu biex jaħżnu. 696 00:31:28,710 --> 00:31:32,680 Aħna ser sejħa dan temperaturi għall-fini ta 'nomenklatura ta' tismija 697 00:31:32,680 --> 00:31:34,200 xi ħaġa li aħna kollha jifhmu. 698 00:31:34,200 --> 00:31:35,900 U aħna qed tmur biex ikollhom parentesi kwadri. 699 00:31:35,900 --> 00:31:37,200 U rridu tliet numri. 700 00:31:37,200 --> 00:31:39,000 Allura aħna qed tmur biex tqiegħed tlieta ġewwa ta 'dan. 701 00:31:39,000 --> 00:31:41,041 >> Xi ħaġa li tassew importanti li wieħed iżomm f'moħħu 702 00:31:41,041 --> 00:31:43,530 hija li arrays huma żero indiċjati. 703 00:31:43,530 --> 00:31:46,410 Dak kollu li jfisser hu li inti tibda bl-indiċi ta '0, 704 00:31:46,410 --> 00:31:49,800 u inti mixja permezz tal- daqs tal-array minus 1. 705 00:31:49,800 --> 00:31:52,730 Hekk per eżempju hawn, aħna jkollhom firxa ta 'daqs 3. 706 00:31:52,730 --> 00:31:54,680 Li għaddej biex tkun tista ' li jżommu tliet valuri. 707 00:31:54,680 --> 00:31:57,450 Iżda n-numri themselves-- li numru, il-firxa, l-indiċi, 708 00:31:57,450 --> 00:32:00,271 l-array, huma 0 sa 2. 709 00:32:00,271 --> 00:32:03,520 Allura guys, tkun tassew, tassew attenti meta int ser permezz ta 'problemi tiegħek stabbiliti 710 00:32:03,520 --> 00:32:06,500 u l-ħolqien xi tip ta 'firxa, peress li ħafna mid-drabi huwa 711 00:32:06,500 --> 00:32:08,490 tassew, tassew faċli li tinsa dan. 712 00:32:08,490 --> 00:32:11,840 I attwalment ma jkollhom l-indiċi ta '3, li jien bħalissa biss 713 00:32:11,840 --> 00:32:13,130 għandhom l-indiċi ta '2. 714 00:32:13,130 --> 00:32:16,046 U jekk inti tipprova aċċess għall-tielet indiċi, 715 00:32:16,046 --> 00:32:18,170 li għaddej biex tkun x'hemm imsejjaħ il-terminatur null. 716 00:32:18,170 --> 00:32:19,990 Huwa mhux se attwalment jeżistu fil-firxa. 717 00:32:19,990 --> 00:32:21,781 U l-kompjuter huwa mhux ser bħal dik. 718 00:32:21,781 --> 00:32:24,570 Sabiex ikunu attenti meta int aċċess affarijiet biss 719 00:32:24,570 --> 00:32:28,070 biex tiżgura li tiftakar li arrays huma żero indiċjati. 720 00:32:28,070 --> 00:32:28,880 >> KOLLOX SEW. 721 00:32:28,880 --> 00:32:34,030 Allura l-ewwel eżempju huwa biss mod wieħed kif tinħoloq sensiela. 722 00:32:34,030 --> 00:32:36,790 It-tieni eżempju I jkollhom hawn taħt huwa biss mod separat 723 00:32:36,790 --> 00:32:40,210 tal-ħolqien x'inhi l-istess data struttura li konna biss inputted. 724 00:32:40,210 --> 00:32:44,347 Allura minflok fiżikament tmexxija permezz ta 'u t-tqegħid fit-temperatura ta' 0 725 00:32:44,347 --> 00:32:47,180 ugwali tkun xi tkun, temperatura 1 ugwali tkun xi tkun, temperatura 2 ugwali 726 00:32:47,180 --> 00:32:50,950 kwalunkwe, I jistgħu attwalment biss direttament joħolqu dan kollu f'linja waħda 727 00:32:50,950 --> 00:32:53,010 fis temperatura parentesi kwadri ugwali. 728 00:32:53,010 --> 00:32:56,536 >> U avviż f'dan il-każ, inti m'għandekx bżonn li jiġi speċifikat kif kbar firxa tiegħek, 729 00:32:56,536 --> 00:32:59,160 minħabba li l-kompjuter għaddej biex jgħaddu u tara li hemm 730 00:32:59,160 --> 00:33:01,570 tliet elementi f'dawk ċineg kaboċċi. 731 00:33:01,570 --> 00:33:04,000 U li għaddej biex tkun taf, OK, I bżonn ta 'firxa ta' daqs 3. 732 00:33:04,000 --> 00:33:07,440 Int mhux ser jeħtieġ li input huwa l-mod li ġej. 733 00:33:07,440 --> 00:33:10,170 >> U wkoll, yeah, li mod. 734 00:33:10,170 --> 00:33:12,610 Ħadd ma jkollu mistoqsijiet rigward kif nagħmlu arrays 735 00:33:12,610 --> 00:33:17,391 jew kif l-istruttura ta 'firxa xogħlijiet? 736 00:33:17,391 --> 00:33:17,890 Yeah. 737 00:33:17,890 --> 00:33:18,806 >> UDJENZA: [inaudible]? 738 00:33:18,806 --> 00:33:21,649 739 00:33:21,649 --> 00:33:22,690 ANDI Peng: Yeah, eżattament. 740 00:33:22,690 --> 00:33:26,150 Mela jekk ġejt biex tiddikjara u initialize firxa tal-metodu li ġej, 741 00:33:26,150 --> 00:33:28,477 li hija t-tieni mod, inti tista 'biss leave dawk. 742 00:33:28,477 --> 00:33:30,310 U l-kompjuter awtomatikament jaf li 743 00:33:30,310 --> 00:33:33,950 jeħtieġ li jgħoddu kemm elementi huma f'dawk ċineg kaboċċi, separati 744 00:33:33,950 --> 00:33:34,930 b'virgoli. 745 00:33:34,930 --> 00:33:37,517 >> Allura hawn jaraw 65, 87, 30. 746 00:33:37,517 --> 00:33:39,600 Allura l-kompjuter jaf, oh, hemm tliet numri interi. 747 00:33:39,600 --> 00:33:45,960 Naf li jinħoloq isem array temperatura bi tliet elementi fiha. 748 00:33:45,960 --> 00:33:46,590 Tajba kwistjoni. 749 00:33:46,590 --> 00:33:47,090 Yeah. 750 00:33:47,090 --> 00:33:51,590 >> UDJENZA: Hux possibbli li jinħolqu firxa ma 'tipi differenti ta' data 751 00:33:51,590 --> 00:33:53,021 li jistgħu jiddaħħlu fis dan? 752 00:33:53,021 --> 00:33:56,746 Per eżempju, ma 'interi [inaudible]? 753 00:33:56,746 --> 00:33:59,120 ANDI Peng: Għall-iskopijiet ta 'din il-klassi, l-ebda, id-dritt issa. 754 00:33:59,120 --> 00:34:03,070 Meta inti toħloq data istruttura bħal firxa, 755 00:34:03,070 --> 00:34:04,990 int javżak l- kompjuter, ħej, I ħtieġa li inti 756 00:34:04,990 --> 00:34:08,159 li jalloka dan ħafna memorja fil-hard drive tiegħi, 757 00:34:08,159 --> 00:34:10,690 ma 'ċellola li tkun Ċertu numru ta 'bits. 758 00:34:10,690 --> 00:34:13,429 >> Ftakar aħna tgħallimna fil-ġimgħa żero, li data differenti 759 00:34:13,429 --> 00:34:15,300 tipi għandhom daqsijiet differenti? 760 00:34:15,300 --> 00:34:17,630 Hekk per eżempju, string huwa ammont differenti 761 00:34:17,630 --> 00:34:20,719 ta 'spazju minn char, li huwa ammont differenti ta 'spazju 762 00:34:20,719 --> 00:34:21,830 minn numru sħiħ. 763 00:34:21,830 --> 00:34:25,534 U hekk jekk inti ma jispeċifikawx u inti ħawwad u jaqblu liema tipi ta 'varjabbli 764 00:34:25,534 --> 00:34:27,659 ikollok, l-tal-kompjuter se tkun ħafna konfuż. 765 00:34:27,659 --> 00:34:29,950 U mhuwiex ser tkun taf kemm memorja li jtik. 766 00:34:29,950 --> 00:34:32,480 Allura għal finijiet ta 'dritt issa, kompjuters tista 'biss 767 00:34:32,480 --> 00:34:36,120 jirrikonoxxu tip wieħed ta 'firxa. 768 00:34:36,120 --> 00:34:37,940 Tajba kwistjoni. 769 00:34:37,940 --> 00:34:38,440 KOLLOX SEW. 770 00:34:38,440 --> 00:34:45,179 771 00:34:45,179 --> 00:34:47,120 >> Allura naturalment, il- tieni domanda għandna 772 00:34:47,120 --> 00:34:50,760 hija, ukoll, issa li konna ħolqot firxa u konna jitqiegħdu kollha ta 'dawn l-affarijiet 773 00:34:50,760 --> 00:34:54,190 fil-array, kif aħna se tkun tista 'aċċess għaliha? 774 00:34:54,190 --> 00:34:59,710 Allura l-istruttura tipika li aħna dejjem ikollhom aċċess għal firxa hija sabiħ tagħna għall loop. 775 00:34:59,710 --> 00:35:03,830 I wegħda inti guys li aħna ser tkun jaraw ħafna ta 'dan sħabi hawn. 776 00:35:03,830 --> 00:35:06,470 >> Essenzjalment, ghaċ tixtieq li l-input valuri fi array 777 00:35:06,470 --> 00:35:09,940 jew inti tixtieq li aċċess għalihom, l- aħjar mod biex tagħmel dan huwa għall loop, 778 00:35:09,940 --> 00:35:13,730 għaliex fil-għal loop, inti taf kif ħafna drabi int 779 00:35:13,730 --> 00:35:17,290 tmur jridu jgħaddi mill-firxa, għax għandek Edizzjoni waqfien, id-dritt? 780 00:35:17,290 --> 00:35:19,680 U kull darba li inti tmexxi permezz, inti tista 'aċċess 781 00:35:19,680 --> 00:35:21,310 element differenti mill-firxa. 782 00:35:21,310 --> 00:35:26,920 >> U wkoll, dan huwa raġuni għaliex tipikament nibdew tagħna għal-linji lejn il-valur ta '0, 783 00:35:26,920 --> 00:35:30,080 għaliex meta inti tagħmel aċċess arrays, inti tista 'aċċess l-indiċi żero. 784 00:35:30,080 --> 00:35:32,070 U għalhekk paralleli ħafna nicely. 785 00:35:32,070 --> 00:35:35,295 You guys jista 'jkollhom riedu tikteb int i ugwali 1. 786 00:35:35,295 --> 00:35:37,330 i huwa inqas minn jew daqs 3. 787 00:35:37,330 --> 00:35:39,890 >> Iżda dan ma tkunx taħdem daqshekk sew hawnhekk, għaliex inti biss 788 00:35:39,890 --> 00:35:42,010 jkollhom elementi ta '0, 1, u 2. 789 00:35:42,010 --> 00:35:45,815 U hekk jekk ġejt biex tibda i tiegħek fuq element 1, 2, u 3, 790 00:35:45,815 --> 00:35:48,440 int ser jispiċċaw running mill-limiti ta 'firxa tiegħek, 791 00:35:48,440 --> 00:35:50,440 u affarijiet ħżiena se jiġri. 792 00:35:50,440 --> 00:35:54,480 >> So I hope inti guys tara l segue ta 'għaliex fil-klassijiet preċedenti 793 00:35:54,480 --> 00:35:58,560 konna tagħlim inti guys kif tmexxi u format għall loop-mod li konna. 794 00:35:58,560 --> 00:36:01,900 Huwa minħabba, issa konna transitioned fis arrays, 795 00:36:01,900 --> 00:36:06,760 tista 'tara għaliex l jsellef 0 ruħha ħafna nicely għall-aċċess. 796 00:36:06,760 --> 00:36:09,880 >> Allura l-mod kif nagħmlu dan huwa that-- jien biss istampar out here għall-fini 797 00:36:09,880 --> 00:36:10,830 tal-istampar out. 798 00:36:10,830 --> 00:36:13,750 Imma jien placeholder tiegħi, comma. 799 00:36:13,750 --> 00:36:15,645 U l-aċċess attwali parti li qed jiġri. 800 00:36:15,645 --> 00:36:17,520 L-isem tal-firxa kienet imsejħa temperatura. 801 00:36:17,520 --> 00:36:21,570 Allura huwa temperatura u l- i-th element tal-firxa. 802 00:36:21,570 --> 00:36:24,400 >> Sabiex il-għar loop runs permezz, li għaddej biex tibda '0. 803 00:36:24,400 --> 00:36:27,640 Huwa ser jistampa l- Indiċi 0 ta 'din array. 804 00:36:27,640 --> 00:36:29,599 Imbagħad li għaddej biex jistampaw l-ewwel element. 805 00:36:29,599 --> 00:36:31,431 Imbagħad li għaddej biex jistampaw l-tieni waħda. 806 00:36:31,431 --> 00:36:32,880 U allura aħna qed tmur biex jinkiser. 807 00:36:32,880 --> 00:36:36,718 Hija kulħadd ċar fuq kif dan qed jiġri? 808 00:36:36,718 --> 00:36:37,217 Great. 809 00:36:37,217 --> 00:36:43,230 810 00:36:43,230 --> 00:36:44,100 >> Kull dritt. 811 00:36:44,100 --> 00:36:47,270 Allura hawnhekk għandna mod ta ' qal, jekk aħna ma riedx 812 00:36:47,270 --> 00:36:50,020 li hard-kodiċi in-- lili bħala l-programmer. 813 00:36:50,020 --> 00:36:53,320 I ma riedx li attwalment fiżikament jitqiegħdu f'kull element individwali 814 00:36:53,320 --> 00:36:54,020 ta 'dan array. 815 00:36:54,020 --> 00:36:56,500 Jekk jien ridt li minflok għandhom l-valuri input utent, 816 00:36:56,500 --> 00:36:58,100 x'inhu l-aħjar mod biex tagħmel dan? 817 00:36:58,100 --> 00:37:00,920 >> Well, here I ħolqu din il-funzjoni sabiħ, 818 00:37:00,920 --> 00:37:03,560 fejn nista 'niddikjara firxa. 819 00:37:03,560 --> 00:37:06,210 Mela int scores-- ejja biss jgħidu irridu li jagħmlu 820 00:37:06,210 --> 00:37:10,660 firxa li kellu l-gradi ta 'kull 18 ta 'l-istudenti hawn f'din it-taqsima. 821 00:37:10,660 --> 00:37:12,670 I think we ve ltqajna daqsxejn aktar minn 18 gidjien llum. 822 00:37:12,670 --> 00:37:16,460 Iżda per eżempju s sake, ejja biss wieħed jassumi kellna 18. 823 00:37:16,460 --> 00:37:21,580 I joħloq punteġġi isem array ma int tip, minħabba punteġġi, naturalment, 824 00:37:21,580 --> 00:37:22,987 huma numri. 825 00:37:22,987 --> 00:37:24,820 U jien ser ikollhom 18 fil-parentesi kwadri, 826 00:37:24,820 --> 00:37:29,900 għaliex li kif ħafna studenti I jridu jkunu kapaċi li jaħżen għexieren ta '. 827 00:37:29,900 --> 00:37:32,206 >> U l-mod I d timla il-firxa hija li I d 828 00:37:32,206 --> 00:37:35,572 run permezz ta 'għall loop, ta Naturalment, b'0 jkunu indiċi 0 tiegħi. 829 00:37:35,572 --> 00:37:38,030 U mbagħad bi 18 qed tiegħi waqfien edizzjoni, għaliex hemm 830 00:37:38,030 --> 00:37:39,690 18 elementi fil-firxa. 831 00:37:39,690 --> 00:37:44,620 U allura jien ser tagħmel printf, Ikteb skorja għal student-- yada yada yada. 832 00:37:44,620 --> 00:37:51,171 >> Jista 'xi ħadd tell me għaliex hawn jien istampar i plus 1 u ma i? 833 00:37:51,171 --> 00:37:52,920 Huwa tip ta 'trick kwistjoni, mhux verament. 834 00:37:52,920 --> 00:37:56,020 Ma attwalment fiżikament jaffettwa l-funzjonament tal-kodiċi. 835 00:37:56,020 --> 00:37:56,520 Yeah. 836 00:37:56,520 --> 00:37:57,909 >> UDJENZA: [inaudible] 0? 837 00:37:57,909 --> 00:37:58,950 ANDI Peng: Yeah, eżattament. 838 00:37:58,950 --> 00:38:02,620 Huwa daqsxejn skomda li jgħidu, ħej, int l-istudent 0 f'din il-klassi. 839 00:38:02,620 --> 00:38:03,780 Huwa daqsxejn stramb. 840 00:38:03,780 --> 00:38:08,340 Allura għalina, bħala bnedmin, ma verament bħall jaħseb kemm kompjuters jaħsbu. 841 00:38:08,340 --> 00:38:10,930 Għalhekk anki jekk fil- kompjuter, huwa ħażna valuri 842 00:38:10,930 --> 00:38:13,310 fl-indiċi 0-th, meta aħna qed bnedmin, aħna ma verament 843 00:38:13,310 --> 00:38:15,520 tixtieq tirreferi għall ruħna bħala żero. 844 00:38:15,520 --> 00:38:18,119 Allura meta I biss print li, Jien ser jistampaw u żid 845 00:38:18,119 --> 00:38:19,410 1 biss għall-fini ta 'ċarezza. 846 00:38:19,410 --> 00:38:22,447 Allura meta I jistampaw, jien ser tkun kapaċi li jistampa istudenti 1 sa 18. 847 00:38:22,447 --> 00:38:24,530 Din attwalment ma jkollhom impatt it-tmexxija tal-kodiċi 848 00:38:24,530 --> 00:38:27,110 fi kwalunkwe mod, il-mod I jistampaw. 849 00:38:27,110 --> 00:38:30,380 >> Imma jkun attent meta int fil-fatt aċċess għall-firxa. 850 00:38:30,380 --> 00:38:32,780 Meta tara l-punteġġi I, Avviż hawn jien attwalment 851 00:38:32,780 --> 00:38:38,200 aċċess għall-indiċi 0 u mhux l-1 flimkien mal 0-- jew 1 flimkien ma '1, 852 00:38:38,200 --> 00:38:45,530 f'dan il-każ, indiċi hekk li huwa attwalment ċar. 853 00:38:45,530 --> 00:38:48,870 Huwa kulħadd tip ta OK fuq kif dan qed taħdem permezz 854 00:38:48,870 --> 00:38:51,470 u ma 'kull indiċi jien tqegħid valur fil-firxa 855 00:38:51,470 --> 00:38:55,340 u tinħoloq sensiela bi 18-numri li l-utent se input? 856 00:38:55,340 --> 00:38:58,780 857 00:38:58,780 --> 00:38:59,821 KOLLOX SEW. 858 00:38:59,821 --> 00:39:00,321 Kessaħ. 859 00:39:00,321 --> 00:39:05,380 860 00:39:05,380 --> 00:39:07,400 >> KOLLOX SEW. 861 00:39:07,400 --> 00:39:12,220 Aħna issa jersqu lejn xi ħaġa li pjuttost rilevanti għal din il-biċċa sett kif ukoll. 862 00:39:12,220 --> 00:39:15,020 Naf fl lecture, David-- sorry, kellek kwistjoni? 863 00:39:15,020 --> 00:39:16,840 >> UDJENZA: Tista tkabbar dan? 864 00:39:16,840 --> 00:39:18,080 >> ANDI Peng: Yeah, so I ppruvaw. 865 00:39:18,080 --> 00:39:18,788 Imma I do not know. 866 00:39:18,788 --> 00:39:21,437 Għal xi raġuni, din Verżjoni tal-PowerPoint 867 00:39:21,437 --> 00:39:23,270 huwa verament ma tkunx qed taħdem sew mal-wiri. 868 00:39:23,270 --> 00:39:25,260 Allura aħna qed biss jmorru biex jżommha bħal dan. 869 00:39:25,260 --> 00:39:27,280 Dawn kollha se jittella online. 870 00:39:27,280 --> 00:39:28,218 Jiddispjacini, guys. 871 00:39:28,218 --> 00:39:30,090 Yeah. 872 00:39:30,090 --> 00:39:30,980 KOLLOX SEW. 873 00:39:30,980 --> 00:39:35,530 >> Allura nistgħu wkoll ikollhom kordi. 874 00:39:35,530 --> 00:39:39,320 Mela jekk inti guys attwalment notice-- I jafu Rob marru fuq dan li lecture 875 00:39:39,320 --> 00:39:43,652 li hu did-- string huwa attwalment biss firxa ta 'karattri, 876 00:39:43,652 --> 00:39:44,860 jekk inti taħseb dwarha, id-dritt? 877 00:39:44,860 --> 00:39:47,500 A string huwa isem jew sentenza jew kelma, right? 878 00:39:47,500 --> 00:39:52,975 >> I Jekk kellhom joħolqu string jismu Andi-- biss isem tiegħi, A-N-D-I. 879 00:39:52,975 --> 00:39:55,460 Inti taħseb li bħala wieħed biss varjabbli. 880 00:39:55,460 --> 00:39:58,630 Imma attwalment, huwa maqsuma fis biss firxa ta 'Chars. 881 00:39:58,630 --> 00:40:01,910 Allura huwa ltqajna karattru ta a maħżuna valur array. 882 00:40:01,910 --> 00:40:05,420 Huwa ltqajna karattru ta 'n maħżuna fil- tieni indiċi u hekk u ibqa 'sejjer hekk. 883 00:40:05,420 --> 00:40:08,660 >> Dan b'tali mod, aħna fil-fatt dan it-tip 884 00:40:08,660 --> 00:40:10,970 ta 'struttura stabbilita fil post ta 'sekwenzi tagħna. 885 00:40:10,970 --> 00:40:14,660 Allura hawnhekk, jekk I kellhom input il- kelma "jieklu" - sabiex kelma string ugwali 886 00:40:14,660 --> 00:40:15,540 nikseb string. 887 00:40:15,540 --> 00:40:19,260 I Jekk kellhom input il-kelma "jieklu," li huwa fiżikament l-mod li l-kompjuter tiegħi 888 00:40:19,260 --> 00:40:21,870 huwa ħażna li string fil-memorja tiegħi. 889 00:40:21,870 --> 00:40:27,140 >> U jekk jien ridt li tgħaddi minn ġos li u print li out-- hekk għal fis i 890 00:40:27,140 --> 00:40:30,890 ugwali żero, ftakar, fil lecture, aħna xi ħaġa koperta li sejjaħ strlen, 891 00:40:30,890 --> 00:40:32,990 jew it-tul tas-sekwenza. 892 00:40:32,990 --> 00:40:36,520 Minħabba I ma attwalment taf kemm tkun kbira l-firxa hija 893 00:40:36,520 --> 00:40:38,210 ta 'kwalunkwe inputting---utent 894 00:40:38,210 --> 00:40:40,370 >> Per eżempju, I inputted il-kelma "jieklu," u I know 895 00:40:40,370 --> 00:40:41,870 dan huwa tliet karattri fit-tul, id-dritt? 896 00:40:41,870 --> 00:40:44,700 So I tista 'tpoġġi fil-tliet hemmhekk u kollox se jkun multa. 897 00:40:44,700 --> 00:40:49,290 Imma jekk xi ħaġa jintuza mill-utent tiegħek li l-numru differenti ta 'valuri, 898 00:40:49,290 --> 00:40:52,760 int ser ma tkun tista 'verament jafu li meta inti program kodiċi tiegħek. 899 00:40:52,760 --> 00:40:56,040 >> Allura l-mod li nittrattaw każijiet ta 'eżaminazzjoni bħal dik hija li aħna għandna xi ħaġa 900 00:40:56,040 --> 00:41:00,070 imsejħa strlen, li huwa biss funzjoni li jgħidlek kemm żmien string hu. 901 00:41:00,070 --> 00:41:02,080 Allura strlen tal-kelma. 902 00:41:02,080 --> 00:41:03,470 Kelma tiegħi huwa tiekol. 903 00:41:03,470 --> 00:41:05,990 n huwa daqs strlen tal-kelma. 904 00:41:05,990 --> 00:41:08,930 Jista 'xi ħadd tell me dak li valur attwalment huwa dritt hemm? 905 00:41:08,930 --> 00:41:12,550 Xi jfisser n jirrappreżenta dritt issa, f'dan l-eżempju, jekk kelli jieklu? 906 00:41:12,550 --> 00:41:13,530 >> UDJENZA: 3. 907 00:41:13,530 --> 00:41:14,520 >> ANDI Peng: 3, eżattament. 908 00:41:14,520 --> 00:41:18,820 Allura aħna għandna biex i int ugwali żero, n ugwali 3, essenzjalment. 909 00:41:18,820 --> 00:41:22,355 U i se jimxu sakemm ikun inqas minn 3i ++. 910 00:41:22,355 --> 00:41:24,980 U li għaddej biex tmur essenzjalment permezz ta 'u jagħmlu l-istess ħaġa. 911 00:41:24,980 --> 00:41:26,979 Li għaddej biex jistampa kull valur u jagħtuk 912 00:41:26,979 --> 00:41:29,700 E-A-T. Huwa biss li turi Mod differenti ta 'kitba dan. 913 00:41:29,700 --> 00:41:31,170 Li għaddej biex jkun ferm utli. 914 00:41:31,170 --> 00:41:31,670 Yeah. 915 00:41:31,670 --> 00:41:35,174 UDJENZA: X'hemm l-benefiċċji ta 'tqegħid il n ugwali kelma strlen ġewwa li 916 00:41:35,174 --> 00:41:36,894 għall loop [inaudible]? 917 00:41:36,894 --> 00:41:37,560 ANDI Peng: Yeah. 918 00:41:37,560 --> 00:41:44,880 Mela jekk jien kienu to-- ngħid, per eżempju, jekk jien kienu li tagħmel dan u mbagħad 919 00:41:44,880 --> 00:41:51,935 do-- oop-- li, fil-kodiċi tiegħi, ikun fil-fatt tkun qiegħda tagħmel bħall-istess ħaġa. 920 00:41:51,935 --> 00:41:55,060 Madankollu, il-mod li David spjegat matul lecture, jekk ikun hemm minnkom guys 921 00:41:55,060 --> 00:41:57,854 ftakar, kienet li, bħal bnedmin, kif programmaturi, 922 00:41:57,854 --> 00:42:00,270 aħna verament jippruvaw programm tagħna kodiċi sabiex il-kompjuter tagħna 923 00:42:00,270 --> 00:42:04,070 biex jaħdmu minimi kemm jista 'jkun, hekk dan il-kodiċi tagħna hija effiċjenti ħafna. 924 00:42:04,070 --> 00:42:06,850 >> Mela jekk kelli li hemm, dak jiġri permezz ta loop tiegħi 925 00:42:06,850 --> 00:42:10,790 hija li I d ewwel tiddikjara i jismu varjabbli se jkun 0. 926 00:42:10,790 --> 00:42:13,350 I am ser jiċċekkja, oh, dak li huwa l-strlen ta kelma? 927 00:42:13,350 --> 00:42:15,000 Oh, il-strlen huwa 3. 928 00:42:15,000 --> 00:42:16,191 Allura huwa i inqas minn tliet? 929 00:42:16,191 --> 00:42:16,690 Iva hekk hu. 930 00:42:16,690 --> 00:42:17,870 Jien ser jimxu. 931 00:42:17,870 --> 00:42:21,130 >> U allura l-tieni darba lura madwar il loop, jien ser inkrement i. 932 00:42:21,130 --> 00:42:22,550 i se tkun waħda. 933 00:42:22,550 --> 00:42:25,600 U i se jivverifikaw, oh, imma x'inhu l-strlen tal-kelma? 934 00:42:25,600 --> 00:42:26,839 Oh, huwa tlieta. 935 00:42:26,839 --> 00:42:29,880 U ma li jidhru-tip ta 'ħela, kull darba li inti tmexxi permezz tal-linja, 936 00:42:29,880 --> 00:42:33,340 li jiġi verifikat l-funzjoni, anki jekk il-strlen ta kelma 937 00:42:33,340 --> 00:42:35,490 fatt qatt bidliet? 938 00:42:35,490 --> 00:42:38,590 >> Allura huwa enerġija żejda għal kompjuter. 939 00:42:38,590 --> 00:42:42,180 Meta inti tibda titkellem dwar affarijiet li huma biljuni u biljuni 940 00:42:42,180 --> 00:42:44,431 u biljuni ta 'postijiet twil, jimmaġina kompjuter tiegħek 941 00:42:44,431 --> 00:42:47,430 jkollhom jgħaddu fiżikament permezz ta 'u iċċekkja kollha ta 'dak kull wieħed ħin. 942 00:42:47,430 --> 00:42:53,170 Dan hu għaliex, li jagħmlu biss għall-fini ta 'effiċjenza, 943 00:42:53,170 --> 00:42:57,620 għandna t-tendenza li biss tagħmel dan, għaliex dan il-mod aħna qed biss 944 00:42:57,620 --> 00:42:59,850 sejħa tal-funzjoni darba fil-bidu, 945 00:42:59,850 --> 00:43:01,766 u li kull darba li tmur permezz li għaddej 946 00:43:01,766 --> 00:43:03,789 biex jaħżnu l-valur 3 hemm, li inti ma 947 00:43:03,789 --> 00:43:05,330 għandhom jiċċekkjaw kontinwament kull darba. 948 00:43:05,330 --> 00:43:05,743 Yeah. 949 00:43:05,743 --> 00:43:06,409 >> UDJENZA: Jiddispjacini. 950 00:43:06,409 --> 00:43:09,070 Just [inaudible]. 951 00:43:09,070 --> 00:43:13,985 Tista do int n ugwali strlen u mqiegħda li 'l fuq barra tal-linja għall 952 00:43:13,985 --> 00:43:15,364 kif ukoll? 953 00:43:15,364 --> 00:43:16,030 ANDI Peng: Yeah. 954 00:43:16,030 --> 00:43:17,100 Inti tista 'tagħmel dan, assolutament. 955 00:43:17,100 --> 00:43:19,970 Ir-raġuni aħna għandna hija fil hawn huwa minħabba li l-mod għal xogħlijiet loop 956 00:43:19,970 --> 00:43:23,500 huwa li huwa msejjaħ varjabbli lokali fis-sens 957 00:43:23,500 --> 00:43:26,150 li kollox int ħolqien ġewwa tal-linja għall 958 00:43:26,150 --> 00:43:27,890 jeżisti biss ġewwa tal-linja għall. 959 00:43:27,890 --> 00:43:31,530 >> Allura l-varjabbli i biss teżisti f'dawk parentesi. 960 00:43:31,530 --> 00:43:35,260 U hawn l-varjabbli ta 'n ukoll teżisti biss f'dawk parentesi. 961 00:43:35,260 --> 00:43:39,350 Mela jekk ġejt biex tuża strlen ta kelma minn darba isfel hawn taħt, 962 00:43:39,350 --> 00:43:42,230 assolutament l-aħjar mod biex tagħmel dan huwa li jiġi ddikjarat it up-quċċata 963 00:43:42,230 --> 00:43:43,563 sabiex inti ma għandekx tagħmel dan darba. 964 00:43:43,563 --> 00:43:45,420 Yeah. 965 00:43:45,420 --> 00:43:47,670 UDJENZA: Għaliex għandek linja ġdida wara l--mija 966 00:43:47,670 --> 00:43:51,300 jaraw jekk inti tixtieq li tqiegħed kollha l-ittri li jmiss lilu separati? 967 00:43:51,300 --> 00:43:54,140 >> ANDI Peng: Oh, jien ridt li tipprintjahom kollha fuq kull linja. 968 00:43:54,140 --> 00:43:54,890 Ma jimpurtax. 969 00:43:54,890 --> 00:43:55,890 Yeah, huwa ifformattjar. 970 00:43:55,890 --> 00:43:57,181 Li l-mistoqsija tajba, għalkemm. 971 00:43:57,181 --> 00:43:59,360 Yeah, jekk jien ridt li jistampaw dan kollu fuq biss linja waħda, 972 00:43:59,360 --> 00:44:02,731 I ma jkollhomx il-sing in. 973 00:44:02,731 --> 00:44:03,230 KOLLOX SEW. 974 00:44:03,230 --> 00:44:06,880 Kulħadd tajba? 975 00:44:06,880 --> 00:44:07,500 KOLLOX SEW. 976 00:44:07,500 --> 00:44:08,000 Kessaħ. 977 00:44:08,000 --> 00:44:12,080 978 00:44:12,080 --> 00:44:14,750 >> So I think I tkellmu biżżejjed. 979 00:44:14,750 --> 00:44:20,040 Dawran inti guys biex jgħaddi mill- kodiċi u tell me dak li hu ħażin hawnhekk. 980 00:44:20,040 --> 00:44:21,560 Fejn hi l-bug? 981 00:44:21,560 --> 00:44:26,920 Allura kif tista 'tara, stajt ddikjarat firxa ġdida ta 'sekwenza tip jismu klassi. 982 00:44:26,920 --> 00:44:30,220 U stajt inputted Sam, Jess, u Kim fih. 983 00:44:30,220 --> 00:44:33,400 U jien jippruvaw jistampa l-elementi tal-firxa. 984 00:44:33,400 --> 00:44:36,796 Jista 'xi ħadd tell me għaliex dan huwa ser jagħti lili problemi? 985 00:44:36,796 --> 00:44:39,320 I ser jagħtuk guys 10 sekondi biex jaħsbu dwar dan. 986 00:44:39,320 --> 00:44:55,490 987 00:44:55,490 --> 00:44:56,619 >> KOLLOX SEW. 988 00:44:56,619 --> 00:44:57,118 Yeah? 989 00:44:57,118 --> 00:45:01,972 >> UDJENZA: Huwa l-ċentru tax-xellug daqs 3 jew [inaudible]? 990 00:45:01,972 --> 00:45:02,680 ANDI Peng: Dritt. 991 00:45:02,680 --> 00:45:06,784 Allura kif ħafna drabi huwa dan fil-fatt ser jgħaddi din loop? 992 00:45:06,784 --> 00:45:07,620 >> UDJENZA: Erba. 993 00:45:07,620 --> 00:45:08,070 >> ANDI Peng: Eżattament. 994 00:45:08,070 --> 00:45:09,445 Huwa ser permezz ta 'erba' darbiet. 995 00:45:09,445 --> 00:45:12,250 Li għaddej biex jgħaddi f'0, 1, 2, u 3, 996 00:45:12,250 --> 00:45:15,200 minħabba element tagħhom huwa i huwa inqas minn jew daqs 3. 997 00:45:15,200 --> 00:45:16,960 Huwa mhux se tieqaf meta huwa 2. 998 00:45:16,960 --> 00:45:18,800 Li għaddej biex iżommu għaddejjin sakemm hits 3. 999 00:45:18,800 --> 00:45:21,720 U kif nafu, hemm biss tliet elementi fil-firxa attwali tagħna. 1000 00:45:21,720 --> 00:45:27,260 >> Jekk nippruvaw aċċess għall-raba ' element jew l-indiċi ta '3, 1001 00:45:27,260 --> 00:45:30,357 int ser jintlaqtu x'imkien fil-memorja li ma teżistix. 1002 00:45:30,357 --> 00:45:31,690 Huwa sejjaħ l-terminatur null. 1003 00:45:31,690 --> 00:45:32,856 Xejn għaddej li jkun hemm. 1004 00:45:32,856 --> 00:45:35,324 Kompjuter tiegħek mhix se li jkunu kuntenti ħafna miegħek. 1005 00:45:35,324 --> 00:45:36,170 Yeah. 1006 00:45:36,170 --> 00:45:38,430 Ħadd ma jkollu mistoqsijiet dwar l-għaliex dan kien qed jiġri? 1007 00:45:38,430 --> 00:45:39,679 Li żona komuni biex jiġi evitat. 1008 00:45:39,679 --> 00:45:40,712 Yeah. 1009 00:45:40,712 --> 00:45:45,777 >> UDJENZA: Ma l-ewwel slide għandhom ukoll sensiela ta '2? 1010 00:45:45,777 --> 00:45:46,360 ANDI Peng: Le 1011 00:45:46,360 --> 00:45:49,610 Allura essenzjalment, meta int tagħmel firxa, 1012 00:45:49,610 --> 00:45:51,540 dan id-dritt bracket hemm, li number-- kollha 1013 00:45:51,540 --> 00:45:53,480 huwa tghidlek huwa kif ħafna elementi jien. 1014 00:45:53,480 --> 00:45:55,840 Huwa mhux attwalment javżak me-indiċi ta 'xejn. 1015 00:45:55,840 --> 00:45:58,760 Allura f'dan il-każ, I know I tixtieq li tikteb bi tliet postijiet, 1016 00:45:58,760 --> 00:46:02,690 bi tliet postijiet fiżiċi għal istiva kwalunkwe I tixtieq li żżomm. 1017 00:46:02,690 --> 00:46:04,510 Allura hu għalhekk li n-numru tlieta hemm. 1018 00:46:04,510 --> 00:46:06,560 Madankollu, jekk jien ridt li attwalment jkollhom aċċess għaliha, 1019 00:46:06,560 --> 00:46:11,220 jekk jien ridt ngħid, printf Numru parentesi klassi, allura 1020 00:46:11,220 --> 00:46:14,560 int ser fil-fatt imqiegħda l-indiċi fiżika hemmhekk. 1021 00:46:14,560 --> 00:46:16,330 Yeah, mistoqsija tajba. 1022 00:46:16,330 --> 00:46:20,065 >> UDJENZA: Allura huwa l-fiżika indiċi mistennija li jkunu [inaudible]? 1023 00:46:20,065 --> 00:46:20,940 ANDI Peng: Im sorry. 1024 00:46:20,940 --> 00:46:21,500 Inti tista 'titkellem up a bit? 1025 00:46:21,500 --> 00:46:24,208 >> UDJENZA: Għalhekk hija l-indiċi fiżika [Inaudible] f'kull wieħed mill-kaxxi? 1026 00:46:24,208 --> 00:46:25,260 [Inaudible]? 1027 00:46:25,260 --> 00:46:26,040 >> ANDI Peng: Yeah. 1028 00:46:26,040 --> 00:46:28,970 Hekk jien se jmorru lura għal-lemin hawn. 1029 00:46:28,970 --> 00:46:31,120 Think ta 'dritt hawn. 1030 00:46:31,120 --> 00:46:32,820 Għandna firxa ta 'daqs 3. 1031 00:46:32,820 --> 00:46:35,540 Hemm tliet postijiet, bħal, placeholders fiżika fil hawn. 1032 00:46:35,540 --> 00:46:37,620 Iżda dawn qed jismu 0, 1, u 2. 1033 00:46:37,620 --> 00:46:40,700 Mela jekk jien ridt li jkollhom aċċess għalihom, il-mod li I jkollhom aċċess għalihom 1034 00:46:40,700 --> 00:46:43,480 huwa printf ta 'kwalunkwe ridt fil hawn. 1035 00:46:43,480 --> 00:46:45,485 Int tkun trid jistampaw l-isem ta 'dan, 1036 00:46:45,485 --> 00:46:47,610 għaliex imbagħad il-kompjuter jaf, oh, I bżonn tħares 1037 00:46:47,610 --> 00:46:51,391 f'dan array għall-indiċi 0. 1038 00:46:51,391 --> 00:46:51,890 Yeah. 1039 00:46:51,890 --> 00:46:53,306 Iżda d-daqs ta 'dan ma jbiddilx. 1040 00:46:53,306 --> 00:46:55,492 Id-daqs huwa 3, irrispettivament ta 'kif inti ttikkettati. 1041 00:46:55,492 --> 00:46:58,321 1042 00:46:58,321 --> 00:46:58,820 KOLLOX SEW. 1043 00:46:58,820 --> 00:47:01,387 Kulħadd tajba? 1044 00:47:01,387 --> 00:47:02,970 UDJENZA: Allura kull darba I [inaudible]? 1045 00:47:02,970 --> 00:47:06,357 1046 00:47:06,357 --> 00:47:06,940 ANDI Peng: OK. 1047 00:47:06,940 --> 00:47:13,270 Allura f'dan il-każ, aħna ma verament jsibu rwieħhom dan id-dritt issa fil-kors. 1048 00:47:13,270 --> 00:47:16,760 Iżda nafu li string-- bħal I intqal qabel, string huwa essenzjalment 1049 00:47:16,760 --> 00:47:18,440 firxa ta 'karattri. 1050 00:47:18,440 --> 00:47:21,430 Mela jekk I joħolqu firxa ta 'spag, I tip ta' 1051 00:47:21,430 --> 00:47:24,430 jkollhom firxa ta 'firxa ta 'karattri, id-dritt? 1052 00:47:24,430 --> 00:47:27,720 >> Allura f'dan il-każ, minħabba I jkollhom firxa ta 'kordi, 1053 00:47:27,720 --> 00:47:31,340 jekk ġejt biex input kelma verament twila, li għadu jieħu l-ispazju wieħed biss, 1054 00:47:31,340 --> 00:47:33,230 minħabba li l-sekwenza waħda. 1055 00:47:33,230 --> 00:47:37,492 Imma jekk ġejt biex jaħsbu l-karattri ta 'dak array, 1056 00:47:37,492 --> 00:47:40,450 imbagħad thats bidu ħafna aktar karattri minn xi waħda mill-kliem ieħor 1057 00:47:40,450 --> 00:47:41,372 huma. 1058 00:47:41,372 --> 00:47:42,830 Mhux tassew importanti għad-dritt issa. 1059 00:47:42,830 --> 00:47:44,921 Iżda li biss ġeneralment kif huwa xogħol. 1060 00:47:44,921 --> 00:47:49,750 1061 00:47:49,750 --> 00:47:50,560 >> KOLLOX SEW. 1062 00:47:50,560 --> 00:47:55,840 Allura din hija xi ħaġa I ser tavżak tagħmel ħafna matul il-kors tas-semestru. 1063 00:47:55,840 --> 00:47:57,500 I bżonn għall-mistrieħ vuċi tiegħi. 1064 00:47:57,500 --> 00:47:59,530 Inti guys bżonn biex jistimulaw yourselves. 1065 00:47:59,530 --> 00:48:02,300 A lott ta 'inti probabilment għandek irqad dritt issa. 1066 00:48:02,300 --> 00:48:05,960 Jien inputjar problemi każwali fejn aħna bħala klassi jew inti 1067 00:48:05,960 --> 00:48:09,480 ma 'sieħeb li jmiss biex inti tmur li jonfqu ftit minuti tiddiskuti 1068 00:48:09,480 --> 00:48:14,980 dwar kif aħna tmur dwar isolvi jew il-ħolqien ta 'programm bħal dan. 1069 00:48:14,980 --> 00:48:17,100 >> Allura issa dritt, irridu biex jinħoloq program-- 1070 00:48:17,100 --> 00:48:19,560 aħna qed tmur biex sejħa hija upper.c-- li tikkonverti 1071 00:48:19,560 --> 00:48:24,787 kelma zghar li kien hemm klassi ta 'fuq uppercase string--, sorry. 1072 00:48:24,787 --> 00:48:26,370 Kelma f'qatet, sorry, huwa sinonimu. 1073 00:48:26,370 --> 00:48:28,370 Jien ser jitbiddlu li jfisser l-istess ħaġa. 1074 00:48:28,370 --> 00:48:32,270 1075 00:48:32,270 --> 00:48:33,499 >> Yeah. 1076 00:48:33,499 --> 00:48:34,540 Ħu ftit minuti. 1077 00:48:34,540 --> 00:48:37,130 Ma għandhom ikunu miktub fi kwalunkwe lingwa. 1078 00:48:37,130 --> 00:48:39,890 Biss fil-kodiċi pseudocode jew loġikament kif nixtiequ anke 1079 00:48:39,890 --> 00:48:42,083 tmur dwar kif isir din il-problema. 1080 00:48:42,083 --> 00:48:42,583 Yeah. 1081 00:48:42,583 --> 00:48:49,881 1082 00:48:49,881 --> 00:48:52,780 >> [Konverżazzjoni SIDE] 1083 00:48:52,780 --> 00:49:18,680 1084 00:49:18,680 --> 00:49:22,130 >> I wkoll innutat li inti guys can-- I tip ta 'tara diġà l-programm. 1085 00:49:22,130 --> 00:49:24,600 I raden nuqqas ta 'tiegħi modalità preżentatur hija problema. 1086 00:49:24,600 --> 00:49:27,410 Iżda huwa OK. 1087 00:49:27,410 --> 00:49:30,410 >> [Konverżazzjoni SIDE] 1088 00:49:30,410 --> 00:50:03,589 1089 00:50:03,589 --> 00:50:04,380 Yeah, jekk jogħġbok, guys. 1090 00:50:04,380 --> 00:50:05,400 Come nikseb kandju. 1091 00:50:05,400 --> 00:50:06,372 Come nikseb kandju. 1092 00:50:06,372 --> 00:50:07,698 >> UDJENZA: Iva! 1093 00:50:07,698 --> 00:50:09,958 >> [Konverżazzjoni SIDE] 1094 00:50:09,958 --> 00:50:16,101 1095 00:50:16,101 --> 00:50:18,100 ANDI Peng: Ukoll, yeah, I ser tibda jitfg kandju 1096 00:50:18,100 --> 00:50:20,280 lejn nies li ma jwieġbu l-mistoqsijiet. 1097 00:50:20,280 --> 00:50:22,260 Allura għandek mistoqsijiet kollha risposta. 1098 00:50:22,260 --> 00:50:24,895 Jew I jissoponi nies li do twieġeb mistoqsijiet. 1099 00:50:24,895 --> 00:50:26,070 Yeah, maqlub. 1100 00:50:26,070 --> 00:50:28,570 >> [Konverżazzjoni SIDE] 1101 00:50:28,570 --> 00:51:13,399 1102 00:51:13,399 --> 00:51:14,274 UDJENZA: [inaudible] 1103 00:51:14,274 --> 00:51:17,300 1104 00:51:17,300 --> 00:51:18,340 >> ANDI Peng: Yeah. 1105 00:51:18,340 --> 00:51:19,340 Yeah. 1106 00:51:19,340 --> 00:51:22,840 >> [Konverżazzjoni SIDE] 1107 00:51:22,840 --> 00:51:40,700 1108 00:51:40,700 --> 00:51:41,590 >> Dritt kollox, guys. 1109 00:51:41,590 --> 00:51:44,731 Ħu, bħal, 10 sekondi aktar. 1110 00:51:44,731 --> 00:51:48,210 >> [Konverżazzjoni SIDE] 1111 00:51:48,210 --> 00:52:10,600 1112 00:52:10,600 --> 00:52:11,750 >> OK, guys. 1113 00:52:11,750 --> 00:52:14,920 Allura qabel nibdew tipprova attwalment fiżikament jikteb il-kodiċi, 1114 00:52:14,920 --> 00:52:20,650 drawwa tajba biex jiżviluppaw hija li irridu li l-ewwel tip ta 'raġuni 1115 00:52:20,650 --> 00:52:22,737 out loġikament kif aħna se tagħmel dan. 1116 00:52:22,737 --> 00:52:24,570 Inti tixtieq tagħmel żgur, qabel ma fiżikament 1117 00:52:24,570 --> 00:52:27,210 beda jipprova kodiċi fil Mario, li inti tagħmel 1118 00:52:27,210 --> 00:52:28,870 ċert li inti għandek pseudocode tiegħek. 1119 00:52:28,870 --> 00:52:31,235 Li qed tieħu miegħek permezz dak li għandek bżonn biex joħolqu hekk 1120 00:52:31,235 --> 00:52:33,360 li, meta inti fiżikament jiktbu program tiegħek aktar tard, 1121 00:52:33,360 --> 00:52:36,640 inti tista 'qabda żbalji aħjar fil-kodiċi tiegħek u affarijiet bħal dik. 1122 00:52:36,640 --> 00:52:40,460 >> Allura aħna qed tmur biex tibda biss by-- bl-Ingliż, fil pseudocode, 1123 00:52:40,460 --> 00:52:43,320 ħadd ma tridx tagħti me spjegazzjoni ġeneriku 1124 00:52:43,320 --> 00:52:46,250 ta 'kif aħna tmur dwar kif isir dan? 1125 00:52:46,250 --> 00:52:48,102 Yeah. 1126 00:52:48,102 --> 00:52:49,664 >> UDJENZA: [inaudible]. 1127 00:52:49,664 --> 00:52:50,830 ANDI Peng: Sure, l-ebda inkwiet. 1128 00:52:50,830 --> 00:52:57,233 UDJENZA: Tista titlobha sabiex jew jistaqsu xi ħadd li tikseb string 1-- yeah, spag, 1129 00:52:57,233 --> 00:52:58,160 u then-- 1130 00:52:58,160 --> 00:52:59,826 >> ANDI Peng: Iva, għalhekk dan huwa bidu tajjeb. 1131 00:52:59,826 --> 00:53:01,972 I ser tibda ittajpjar, sorry, kif inti titkellem. 1132 00:53:01,972 --> 00:53:02,471 So-- 1133 00:53:02,471 --> 00:53:05,698 >> UDJENZA: --the zghar numri huma ogħla, id-dritt? 1134 00:53:05,698 --> 00:53:08,519 Jew l-ittri zghar għandhom għadd kbir? 1135 00:53:08,519 --> 00:53:09,310 ANDI Peng: Eżattament. 1136 00:53:09,310 --> 00:53:16,156 UDJENZA: Mela allura aħna naqqas 32 minn kwalunkwe [inaudible]. 1137 00:53:16,156 --> 00:53:28,600 1138 00:53:28,600 --> 00:53:29,870 >> ANDI Peng: Great. 1139 00:53:29,870 --> 00:53:35,020 Allura aħna tip ta jkollhom sens ġenerali ta 'kif taħdem din il-problema. 1140 00:53:35,020 --> 00:53:40,060 Jafu li konna tip ta 'tgħallmu il-mod fiżiku li kordi 1141 00:53:40,060 --> 00:53:43,320 huma maħżuna fil-memorja, liema do inti diġà 1142 00:53:43,320 --> 00:53:45,920 taf li int ser probabbilment jkollhom jiktbu fil-kodiċi tiegħek 1143 00:53:45,920 --> 00:53:48,288 sabiex jimxu permezz-sekwenza? 1144 00:53:48,288 --> 00:53:49,259 >> UDJENZA: Għal loop. 1145 00:53:49,259 --> 00:53:50,550 ANDI Peng: A għall loop, eżattament. 1146 00:53:50,550 --> 00:53:56,540 1147 00:53:56,540 --> 00:53:57,220 Great. 1148 00:53:57,220 --> 00:54:00,539 Allura aħna tip ta jkollhom ġeneriku pseudocode miktub 1149 00:54:00,539 --> 00:54:02,330 dak it-tip ta 'qed tagħti inti noti dwar kif inti 1150 00:54:02,330 --> 00:54:03,900 se jimxu madwar tissolva l-problema. 1151 00:54:03,900 --> 00:54:06,150 Issa li inti għandek dan, inti tista 'referenza għal wara 1152 00:54:06,150 --> 00:54:08,233 fuq meta inti qed tipprova attwalment jikteb il-kodiċi tiegħek. 1153 00:54:08,233 --> 00:54:10,240 Allura nistgħu ngħidu mur hawn. 1154 00:54:10,240 --> 00:54:25,130 U stajt ltqajna funzjoni msejħa upper.c-- hemm it is-- ta 'ftit template vojta 1155 00:54:25,130 --> 00:54:28,510 dritt issa li inti guys huma ser għinni figura dwar kif jiktbu 1156 00:54:28,510 --> 00:54:30,430 din il-linja ta 'code-- ma linja tal-kodiċi. 1157 00:54:30,430 --> 00:54:32,890 Huwa ser jiġi diversi linji ta 'kodiċi. 1158 00:54:32,890 --> 00:54:35,710 >> Meta tibda xi tip tal pset vojt, x'hemm 1159 00:54:35,710 --> 00:54:37,418 l-ewwel ħaġa I bżonn li tiftakar li tagħmel? 1160 00:54:37,418 --> 00:54:39,290 >> UDJENZA: [inaudible]. 1161 00:54:39,290 --> 00:54:41,000 >> ANDI Peng: Great Yep. 1162 00:54:41,000 --> 00:54:41,500 Inkludi. 1163 00:54:41,500 --> 00:54:44,850 1164 00:54:44,850 --> 00:54:47,130 stdio.h. 1165 00:54:47,130 --> 00:54:49,640 Oftentimes dan huwa wieħed mill il-poplu iktar żbalji faċli 1166 00:54:49,640 --> 00:54:51,598 se tagħmel meta jkunu qed miktub, huwa li dawn ser 1167 00:54:51,598 --> 00:54:54,180 ninsewx li tinkludi librerija importanti li għandhom bżonn. 1168 00:54:54,180 --> 00:54:57,689 Mela jekk huwa ħinijiet tal-uffiċċju u int simili, I do not know għaliex kodiċi tiegħi ma taħdimx. 1169 00:54:57,689 --> 00:54:59,230 Tista 'tgħidli għaliex huwa ma tkunx qed taħdem? 1170 00:54:59,230 --> 00:55:00,730 Aħna ser ngħid sirt #include? 1171 00:55:00,730 --> 00:55:02,520 Għandek #include dan. 1172 00:55:02,520 --> 00:55:03,270 KOLLOX SEW. 1173 00:55:03,270 --> 00:55:07,230 >> Allura konna ltqajna l-istandard I / O hawn. 1174 00:55:07,230 --> 00:55:10,740 Huwa li l-unika librerija aħna qed tmur għall-ħtieġa hawn? 1175 00:55:10,740 --> 00:55:12,681 X'iktar huma aħna se jagħmlu? 1176 00:55:12,681 --> 00:55:13,180 Jiddispjacini. 1177 00:55:13,180 --> 00:55:14,562 Xi ħadd biss scream out? 1178 00:55:14,562 --> 00:55:15,666 >> UDJENZA: [inaudible]. 1179 00:55:15,666 --> 00:55:16,666 ANDI Peng: Hemm inti tmur. 1180 00:55:16,666 --> 00:55:20,320 1181 00:55:20,320 --> 00:55:21,440 KOLLOX SEW. 1182 00:55:21,440 --> 00:55:26,070 U kif nista tmur dwar jibdew kwalunkwe tip ta 'funzjoni, kwalunkwe tip ta' funzjoni ewlenija 1183 00:55:26,070 --> 00:55:28,760 fi ħdan programm tagħna? 1184 00:55:28,760 --> 00:55:30,020 Prinċipali Int. 1185 00:55:30,020 --> 00:55:34,531 1186 00:55:34,531 --> 00:55:35,030 KOLLOX SEW. 1187 00:55:35,030 --> 00:55:35,970 What do I jitpoġġew ġo hawn? 1188 00:55:35,970 --> 00:55:37,640 X'inhu l-ewwel ħaġa li trid tagħmel? 1189 00:55:37,640 --> 00:55:39,910 Jekk irridu jiksbu string mill-utent, 1190 00:55:39,910 --> 00:55:43,870 dak li aħna se jkollhom li tagħmel fuq dan l-ewwel linja? 1191 00:55:43,870 --> 00:55:46,120 Jiddispjacini, inti guys biss tħossok ħielsa li jitkellmu u loud. 1192 00:55:46,120 --> 00:55:47,123 Just shout out x'ikun. 1193 00:55:47,123 --> 00:55:48,772 >> UDJENZA: Staqsi lill-utent? 1194 00:55:48,772 --> 00:55:49,980 ANDI Peng: Kif nistgħu nagħmlu dan? 1195 00:55:49,980 --> 00:55:51,873 Ask-- am I se tip "issaqsi lill-utent"? 1196 00:55:51,873 --> 00:55:52,600 >> UDJENZA: printf. 1197 00:55:52,600 --> 00:55:54,341 >> ANDI Peng: OK. 1198 00:55:54,341 --> 00:55:54,840 Printf. 1199 00:55:54,840 --> 00:55:57,372 What do I jridu printf? 1200 00:55:57,372 --> 00:55:58,776 >> UDJENZA: Tip xi ħaġa. 1201 00:55:58,776 --> 00:56:02,760 1202 00:56:02,760 --> 00:56:03,840 >> ANDI Peng: Bħal dak? 1203 00:56:03,840 --> 00:56:05,430 Guys, nippretendu bħal jien kompjuter. 1204 00:56:05,430 --> 00:56:08,475 Fiżikament tell me kull pass li għandi bżonn biex tip fil hawn? 1205 00:56:08,475 --> 00:56:09,600 Am I tagħmel xi ħaġa ħażina? 1206 00:56:09,600 --> 00:56:10,743 Għandi ittajpjat xi ħaġa? 1207 00:56:10,743 --> 00:56:11,690 >> UDJENZA: Għandek bżonn kwotazzjonijiet. 1208 00:56:11,690 --> 00:56:12,380 >> ANDI Peng: I bżonn kwotazzjonijiet? 1209 00:56:12,380 --> 00:56:12,880 KOLLOX SEW. 1210 00:56:12,880 --> 00:56:15,520 1211 00:56:15,520 --> 00:56:16,297 KOLLOX SEW. 1212 00:56:16,297 --> 00:56:17,698 >> UDJENZA: U linja mbagħad ġdid. 1213 00:56:17,698 --> 00:56:21,434 1214 00:56:21,434 --> 00:56:22,465 Virgola. 1215 00:56:22,465 --> 00:56:23,340 ANDI Peng: virgola? 1216 00:56:23,340 --> 00:56:24,060 KOLLOX SEW. 1217 00:56:24,060 --> 00:56:24,560 Tajba. 1218 00:56:24,560 --> 00:56:27,060 >> UDJENZA: U forsi jispeċifika li inti tixtieq li fil lowercase? 1219 00:56:27,060 --> 00:56:30,120 1220 00:56:30,120 --> 00:56:31,415 >> ANDI Peng: Great. 1221 00:56:31,415 --> 00:56:33,540 You guys tidħaq fil lili jinsa li jitqiegħed virgola. 1222 00:56:33,540 --> 00:56:36,350 I garanzija li inti x'imkien fil-kors ta 'din il-klassi, 1223 00:56:36,350 --> 00:56:38,260 inti ser tinsa li jitqiegħdu b'semicolon, u 1224 00:56:38,260 --> 00:56:41,116 se tieħu inti tliet sigħat biex insemmu tispjega għaliex kodiċi tiegħek mhux qed jaħdem. 1225 00:56:41,116 --> 00:56:42,240 Huwa ġara li lkoll. 1226 00:56:42,240 --> 00:56:43,950 Huwa probabbilment se jiġri lilek. 1227 00:56:43,950 --> 00:56:46,352 Get fil-drawwa tajba ta 'użu semicolons. 1228 00:56:46,352 --> 00:56:46,852 KOLLOX SEW. 1229 00:56:46,852 --> 00:56:49,010 >> UDJENZA: Tixtieq li jagħmlu l-backslash fil-? 1230 00:56:49,010 --> 00:56:50,398 >> ANDI Peng: Sure. 1231 00:56:50,398 --> 00:56:51,856 Do inti tixtieq li tagħmel l-backslash fil-? 1232 00:56:51,856 --> 00:56:53,020 >> UDJENZA: Iva. 1233 00:56:53,020 --> 00:56:54,330 >> ANDI Peng: Great. 1234 00:56:54,330 --> 00:56:54,830 KOLLOX SEW. 1235 00:56:54,830 --> 00:56:57,872 What do I do jmiss? 1236 00:56:57,872 --> 00:56:58,964 >> UDJENZA: Get string. 1237 00:56:58,964 --> 00:56:59,880 ANDI Peng: Get string. 1238 00:56:59,880 --> 00:57:03,080 1239 00:57:03,080 --> 00:57:03,830 Mela xi do I tip? 1240 00:57:03,830 --> 00:57:04,233 Xi ħadd? 1241 00:57:04,233 --> 00:57:05,040 >> UDJENZA: String s. 1242 00:57:05,040 --> 00:57:05,873 >> ANDI Peng: String s. 1243 00:57:05,873 --> 00:57:07,251 UDJENZA: GetString. 1244 00:57:07,251 --> 00:57:09,000 ANDI Peng: Xi ħadd, inti tista 'tgħidli fejn 1245 00:57:09,000 --> 00:57:12,000 dan GetString funzjoni huwa li ġejjin minn? 1246 00:57:12,000 --> 00:57:13,660 >> UDJENZA: String.h. 1247 00:57:13,660 --> 00:57:15,256 >> ANDI Peng: String.h? 1248 00:57:15,256 --> 00:57:16,715 Taħseb li huwa mill string.h? 1249 00:57:16,715 --> 00:57:17,830 >> UDJENZA: [inaudible]. 1250 00:57:17,830 --> 00:57:18,830 >> ANDI Peng: Hemm inti tmur. 1251 00:57:18,830 --> 00:57:21,280 Huwa minn CS50.h. 1252 00:57:21,280 --> 00:57:24,530 Jekk inti qed dejjem konfuż fuq fejn fajl librerija hija jew fajl header hija, 1253 00:57:24,530 --> 00:57:28,450 google litteralment string.h, u jien ser jgħidlek 1254 00:57:28,450 --> 00:57:30,450 liema huma l-funzjonijiet li huma fil string.h. 1255 00:57:30,450 --> 00:57:31,340 KOLLOX SEW. 1256 00:57:31,340 --> 00:57:35,210 >> Allura issa li I ħolqu string u stajt pront lill-utent għal dan, 1257 00:57:35,210 --> 00:57:38,770 Stajt maħżuna dan fil-varjabbli i msemmija, liema do I bżonn tagħmel issa? 1258 00:57:38,770 --> 00:57:40,652 >> UDJENZA: Iċċekkja jekk huwa fl zghar. 1259 00:57:40,652 --> 00:57:41,360 ANDI Peng: Jiddispjacini? 1260 00:57:41,360 --> 00:57:42,545 UDJENZA: Iċċekkja jekk huwa fl zghar. 1261 00:57:42,545 --> 00:57:44,045 ANDI Peng: Id-dritt, ejja tagħmel dan. 1262 00:57:44,045 --> 00:57:45,857 Kif nista 'nagħmlu? 1263 00:57:45,857 --> 00:57:47,940 Attwalment, għall-finijiet tal-klassi dritt issa, 1264 00:57:47,940 --> 00:57:50,330 aħna qed biss ser jassumi li kollox 1265 00:57:50,330 --> 00:57:52,620 li aħna input hija diġà fil zghar. 1266 00:57:52,620 --> 00:57:55,430 Jekk int riedu biex jivverifikaw, inti żid ftit stqarrija kondizzjonali 1267 00:57:55,430 --> 00:57:59,640 li iċċekkjata, li dam permezz kull element array wieħed 1268 00:57:59,640 --> 00:58:02,540 u ċċekkjati jekk huwa bejn ċerti valuri. 1269 00:58:02,540 --> 00:58:05,627 Ninsa dak in-numru ta 'valuri ta' zghar huma. 1270 00:58:05,627 --> 00:58:07,210 Inti tista 'tfittex it up fuq il-mejda ASCII. 1271 00:58:07,210 --> 00:58:08,800 Iżda yeah, li l-punt verament tajba. 1272 00:58:08,800 --> 00:58:11,758 Imma issa dritt, aħna qed biss ser wieħed jassumi li l-kordi aħna input 1273 00:58:11,758 --> 00:58:13,130 huma zghar. 1274 00:58:13,130 --> 00:58:13,870 KOLLOX SEW. 1275 00:58:13,870 --> 00:58:18,069 >> Allura kif se mmur dwar din il-problema li jmiss? 1276 00:58:18,069 --> 00:58:18,860 UDJENZA: Għal loop. 1277 00:58:18,860 --> 00:58:19,340 ANDI Peng: Għal loop? 1278 00:58:19,340 --> 00:58:19,839 KOLLOX SEW. 1279 00:58:19,839 --> 00:58:20,847 Tell me dak li tip. 1280 00:58:20,847 --> 00:58:25,230 >> UDJENZA: Għal int i ugwali 0. 1281 00:58:25,230 --> 00:58:27,230 >> ANDI Peng: OK. 1282 00:58:27,230 --> 00:58:36,350 >> UDJENZA: Oh, fil-fatt, imbagħad inti do comma u jagħmlu n jkun ugwali strlen. 1283 00:58:36,350 --> 00:58:38,940 >> ANDI Peng: ħaġa So importanti li naħseb hi tal ndunat hawn 1284 00:58:38,940 --> 00:58:42,936 hija li aħna ma jkollhom jgħidu int n-tieni darba għamilna dan. 1285 00:58:42,936 --> 00:58:45,060 Biss jafu li fil-għal loop meta int tiddikjara, 1286 00:58:45,060 --> 00:58:47,934 inti fil-fatt m'għandhomx bżonn l-int ta it-tieni darba li inti tagħmel varjabbli. 1287 00:58:47,934 --> 00:58:51,202 Tista 'tgħid strlen n. 1288 00:58:51,202 --> 00:58:52,620 >> UDJENZA: Ta s. 1289 00:58:52,620 --> 00:58:53,510 >> ANDI Peng: s. 1290 00:58:53,510 --> 00:58:54,706 KOLLOX SEW. 1291 00:58:54,706 --> 00:58:58,370 >> UDJENZA: Imbagħad virgola. 1292 00:58:58,370 --> 00:59:00,130 >> ANDI Peng: Sure. 1293 00:59:00,130 --> 00:59:04,050 >> UDJENZA: U mbagħad [inaudible] n. 1294 00:59:04,050 --> 00:59:07,480 1295 00:59:07,480 --> 00:59:09,460 Imbagħad i ++. 1296 00:59:09,460 --> 00:59:11,780 >> ANDI Peng: Great. 1297 00:59:11,780 --> 00:59:12,280 Kull dritt. 1298 00:59:12,280 --> 00:59:14,690 What do rridu ġewwa ta 'dan għal loop issa? 1299 00:59:14,690 --> 00:59:17,820 Ftakar, jekk aħna qed tmur biex jgħaddi mill string u mmexxija permezz ta 'firxa, 1300 00:59:17,820 --> 00:59:19,287 irridu li jiċċekkjaw affarijiet fiha. 1301 00:59:19,287 --> 00:59:20,370 Liema huma aħna tmur ħtieġa? 1302 00:59:20,370 --> 00:59:23,070 1303 00:59:23,070 --> 00:59:26,900 Dan huwa tip ta 'l-parti delikata issa. 1304 00:59:26,900 --> 00:59:27,960 Kull min ikollu raden? 1305 00:59:27,960 --> 00:59:34,160 1306 00:59:34,160 --> 00:59:34,690 >> KOLLOX SEW. 1307 00:59:34,690 --> 00:59:37,830 Allura l-ewwel, kif nistgħu anki l-aċċess? 1308 00:59:37,830 --> 00:59:41,610 Kif nistgħu anke ewwel kontroll jew ikollhom aċċess għal element fil-firxa? 1309 00:59:41,610 --> 00:59:42,920 Kif nistgħu nagħmlu dan? 1310 00:59:42,920 --> 00:59:47,120 X'hemm-notazzjoni nużaw biex tagħmel dan? 1311 00:59:47,120 --> 00:59:50,920 X'inhu l-isem ta 'dan array imsejħa? 1312 00:59:50,920 --> 00:59:52,400 Huwa sejjaħ s, id-dritt? 1313 00:59:52,400 --> 00:59:54,850 >> Ftakar, kull spaga hija dejjem firxa. 1314 00:59:54,850 --> 00:59:58,210 Allura s bracket i, id-dritt? 1315 00:59:58,210 --> 01:00:01,360 Minħabba li huwa l-valur attwali jew il-valur indiċi aħna qed iċċekkjar. 1316 01:00:01,360 --> 01:00:05,156 U aħna qed tmur biex ikun stabbilit li ugwali to-- irridu valur lowercase, right? 1317 01:00:05,156 --> 01:00:07,530 Aħna rridu li jduru li lower-- sorry, aħna tixtieq uppercase. 1318 01:00:07,530 --> 01:00:10,014 Aħna rridu li jduru l zghar valur fi uppercase. 1319 01:00:10,014 --> 01:00:11,805 U hekk like-- jien sorry, liema huwa l-isem tiegħek? 1320 01:00:11,805 --> 01:00:12,580 >> UDJENZA: Heidi. 1321 01:00:12,580 --> 01:00:12,940 >> ANDI Peng: Jiddispjacini? 1322 01:00:12,940 --> 01:00:13,280 >> UDJENZA: Heidi. 1323 01:00:13,280 --> 01:00:13,988 >> ANDI Peng: Heidi. 1324 01:00:13,988 --> 01:00:15,850 Bħal Heidi qal inizjalment, aħna qed probabbilment 1325 01:00:15,850 --> 01:00:20,330 ser jeħtieġu the-- aħna qed probabbilment se jkollhom naqqas 1326 01:00:20,330 --> 01:00:22,630 32 minn kwalunkwe charc jiġifieri, id-dritt? 1327 01:00:22,630 --> 01:00:24,680 Minħabba fuq ASCII tabella, id-differenza 1328 01:00:24,680 --> 01:00:27,790 bejn ittra lowercase u ittra uppercase huwa 32. 1329 01:00:27,790 --> 01:00:31,290 Allura meta aħna qed tagħmel dan, aħna qed probabbilment tmur jridu naqqas 32, id-dritt? 1330 01:00:31,290 --> 01:00:33,910 >> Allura aħna qed tmur biex tagħmel s i. 1331 01:00:33,910 --> 01:00:37,590 1332 01:00:37,590 --> 01:00:41,200 Ma kulħadd jifhem għaliex I did li? 1333 01:00:41,200 --> 01:00:45,760 Minħabba dritt issa, fil-array tagħna, aħna qed iċċekkjar tal-indiċi 0, right? 1334 01:00:45,760 --> 01:00:49,190 U fl-indiċi 0 tal- spag, dak l-ewwel karattru. 1335 01:00:49,190 --> 01:00:51,820 U dan il-karattru aħna qed tmur li jassumi huwa zghar. 1336 01:00:51,820 --> 01:00:55,980 Jekk irridu li jagħmilha uppercase, aħna għandek naqqas 32 mill-valur tagħha, 1337 01:00:55,980 --> 01:00:58,620 għaliex fil ASCII tagħna tabella, li kif aħna ġġibu 1338 01:00:58,620 --> 01:01:01,600 għall-ieħor korrispondenti valur li jagħmilha uppercase. 1339 01:01:01,600 --> 01:01:03,714 Ma kulħadd jifhem li? 1340 01:01:03,714 --> 01:01:04,213 Yeah. 1341 01:01:04,213 --> 01:01:06,530 >> UDJENZA: Jista inti ukoll do zghar a minus-- 1342 01:01:06,530 --> 01:01:08,080 >> ANDI Peng: Yeah, b'tali mod li attwalment verament tajba. 1343 01:01:08,080 --> 01:01:10,455 Jien ser terga 'lura għal dik kwistjoni wara nagħmlu dan. 1344 01:01:10,455 --> 01:01:11,060 Yeah. 1345 01:01:11,060 --> 01:01:13,940 U allura jekk irrid tara x'inhu għaddej, 1346 01:01:13,940 --> 01:01:16,180 Jien probabbilment se tixtieq li jistampaw, right? 1347 01:01:16,180 --> 01:01:19,930 Xi ħadd tell me dak I tixtieq li jistampaw hawn. 1348 01:01:19,930 --> 01:01:29,160 >> UDJENZA: fil-mija printf c backslash [inaudible]. 1349 01:01:29,160 --> 01:01:33,570 Dik hija l-valur ta '[inaudible] i i. 1350 01:01:33,570 --> 01:01:34,614 >> ANDI Peng: s i, sorry? 1351 01:01:34,614 --> 01:01:35,530 UDJENZA: [inaudible]. 1352 01:01:35,530 --> 01:01:38,550 1353 01:01:38,550 --> 01:01:39,550 ANDI Peng: I do not know. 1354 01:01:39,550 --> 01:01:40,600 X'tahseb? 1355 01:01:40,600 --> 01:01:44,016 >> UDJENZA: Well, I wouldn't-- I raden I ma bring-- 1356 01:01:44,016 --> 01:01:46,944 Nixtieq oħroġha l- ġewwa, minħabba [inaudible]. 1357 01:01:46,944 --> 01:01:49,726 1358 01:01:49,726 --> 01:01:51,392 ANDI Peng: Oh, inti għamlu dak? 1359 01:01:51,392 --> 01:01:53,867 UDJENZA: Yeah. 1360 01:01:53,867 --> 01:01:56,700 ANDI Peng: Ejja jħallu dan il-mod huwa, u jien ser jispjegaw għaliex aktar tard. 1361 01:01:56,700 --> 01:01:58,533 Ftakar, anki meta inti jkollhom detentur post, 1362 01:01:58,533 --> 01:02:00,701 inti tixtieq li tqiegħed parenteżi madwaru. 1363 01:02:00,701 --> 01:02:01,200 Kull dritt. 1364 01:02:01,200 --> 01:02:04,810 Għalhekk dan għandu jkun funzjoni solida hawn. 1365 01:02:04,810 --> 01:02:06,370 Ejja run u ara jekk jikkompila. 1366 01:02:06,370 --> 01:02:08,750 Jagħmlu fuq. 1367 01:02:08,750 --> 01:02:09,250 Uh-oh. 1368 01:02:09,250 --> 01:02:12,030 1369 01:02:12,030 --> 01:02:13,340 Dan ma tfittex wisq tajbin. 1370 01:02:13,340 --> 01:02:14,507 Għaliex qed jiġri dan? 1371 01:02:14,507 --> 01:02:17,340 Bħal kull żball, inti tixtieq li tmur lura u jibda bl-ewwel waħda, 1372 01:02:17,340 --> 01:02:20,630 minħabba tipikament kawżi ta 'żball wieħed lottijiet ta 'żbalji oħrajn wara. 1373 01:02:20,630 --> 01:02:26,700 Hawnhekk naraw upper.c: 18: 25, li tirrakkonta me f'dan il-programm jismu upper.c, 1374 01:02:26,700 --> 01:02:33,800 fuq il-linja 18, żball impliċitament li tiddikjara librerija ta 'funzjonijiet strlen ma' tip 1375 01:02:33,800 --> 01:02:36,330 blah unassigned--, I do not know x'inhu għaddej wara dik. 1376 01:02:36,330 --> 01:02:39,990 >> Kollha huwa javżak me dritt issa huwa li xi ħaġa għaddej il strlen. 1377 01:02:39,990 --> 01:02:43,520 U tal-kompjuter konfuż, minħabba Huwa simili, I do not know dak strlen hu? 1378 01:02:43,520 --> 01:02:45,520 Xi jfisser li probabbilment jgħidlek int nieqes? 1379 01:02:45,520 --> 01:02:46,490 >> UDJENZA: Inti nieqes [inaudible]. 1380 01:02:46,490 --> 01:02:47,630 >> ANDI Peng: Inti dritt. 1381 01:02:47,630 --> 01:02:49,510 Eżattament. 1382 01:02:49,510 --> 01:02:52,140 Allura dan huwa fejn huwa importanti li jiġi żgurat 1383 01:02:52,140 --> 01:02:56,970 li kull funzjoni tuża fil tiegħek kodiċi qed ikollha l-header korretta 1384 01:02:56,970 --> 01:02:59,660 fajl għall-librerija, jew inkella int ser tikseb lottijiet ta 'żbalji 1385 01:02:59,660 --> 01:03:01,150 u l-kodiċi tiegħek mhix se li tkun taf x'inhu għaddej. 1386 01:03:01,150 --> 01:03:03,050 Allura aħna qed tmur biex jinkludu string.h hawn. 1387 01:03:03,050 --> 01:03:06,270 >> Issa meta nippruvaw biex jikkompilaw fuq. 1388 01:03:06,270 --> 01:03:08,410 Jikkompilaw korrett. 1389 01:03:08,410 --> 01:03:09,960 Ejja run dan il-programm. 1390 01:03:09,960 --> 01:03:12,000 Allura xi ħaġa tip fl zghar. 1391 01:03:12,000 --> 01:03:14,920 What do you guys tixtieq li tip? 1392 01:03:14,920 --> 01:03:16,546 Shout out xi ħaġa. 1393 01:03:16,546 --> 01:03:17,920 Kull dritt, Charly biss mixi fil. 1394 01:03:17,920 --> 01:03:18,990 Aħna ser tip isem Charly tal. 1395 01:03:18,990 --> 01:03:21,670 1396 01:03:21,670 --> 01:03:22,840 >> Charly fl zghar. 1397 01:03:22,840 --> 01:03:27,742 U wieħed jittama, wieħed jittama, dan huwa se shout out u bżiq 1398 01:03:27,742 --> 01:03:28,575 Charly fil uppercase. 1399 01:03:28,575 --> 01:03:30,830 Yay! 1400 01:03:30,830 --> 01:03:33,430 kulħadd ma jifhem kif I marru dwar isolvi dan? 1401 01:03:33,430 --> 01:03:36,190 Il-mod li nista jimmanipulaw jużaw interi 1402 01:03:36,190 --> 01:03:39,410 biex isolvu xi ħaġa li I trid tagħmel f'qatet, 1403 01:03:39,410 --> 01:03:44,390 minħabba karattri u interi jista tiġi referenzjata bl-istess mod minħabba 1404 01:03:44,390 --> 01:03:45,540 tal mapping ASCII. 1405 01:03:45,540 --> 01:03:52,890 >> Allura li jmorru lura għall-punt tiegħek, jekk I riedu li jitqiegħed hawn minflok 32 1406 01:03:52,890 --> 01:03:58,959 uppercase A nieqes zghar a bħad li, li tkun taħdem ugwalment kif ukoll, 1407 01:03:58,959 --> 01:04:01,750 minħabba li sempliċiment biss l differenza bejn dawk iż-żewġ valuri. 1408 01:04:01,750 --> 01:04:09,570 Jekk Irrid nagħmel dan Charly again--. 1409 01:04:09,570 --> 01:04:10,320 Oh no. 1410 01:04:10,320 --> 01:04:11,820 I think we marru l-mod żbaljat, yeah? 1411 01:04:11,820 --> 01:04:13,260 >> UDJENZA: [inaudible] zghar a. 1412 01:04:13,260 --> 01:04:14,260 >> ANDI Peng: Hemm inti tmur. 1413 01:04:14,260 --> 01:04:22,380 1414 01:04:22,380 --> 01:04:22,880 Yep. 1415 01:04:22,880 --> 01:04:24,920 U barra spits Charly. 1416 01:04:24,920 --> 01:04:28,020 Sabiex ikunu attenti meta int jitnaqqas valuri 1417 01:04:28,020 --> 01:04:30,400 biex tiftakar liema waħda hija akbar mill-oħra. 1418 01:04:30,400 --> 01:04:35,220 Per eżempju, hawn I nesa li zghar a huwa attwalment 1419 01:04:35,220 --> 01:04:38,540 akbar minn A. uppercase Allura meta I ppruvaw naqqas minnhom il-mod ieħor 1420 01:04:38,540 --> 01:04:40,600 madwar, sibt negattiv 32. 1421 01:04:40,600 --> 01:04:42,800 U l-kompjuter tiegħi kien simili, I do not know dak li hu. 1422 01:04:42,800 --> 01:04:45,810 Huwa probabbiltà biss ftit każwali valur li mhix tajba ħafna. 1423 01:04:45,810 --> 01:04:48,760 U sabiex tagħmel ċert li int jitnaqqas fit-tul korretta 1424 01:04:48,760 --> 01:04:52,831 biex isibu l-karattru li trid. 1425 01:04:52,831 --> 01:04:53,330 KOLLOX SEW. 1426 01:04:53,330 --> 01:04:58,550 Huwa kwalunkwe persuna konfuż dwar kif aħna marru dwar kitba din il-funzjoni? 1427 01:04:58,550 --> 01:04:59,180 KOLLOX SEW. 1428 01:04:59,180 --> 01:05:04,830 Allura fil-fatt, funzjoni diġà teżisti fil-librerija imsejħa ctype.h. 1429 01:05:04,830 --> 01:05:06,417 Imsejjaħ ctype.h tal-librerija. 1430 01:05:06,417 --> 01:05:08,500 Din il-funzjoni fil-fatt huwa diġà bil-miktub għalik. 1431 01:05:08,500 --> 01:05:10,820 Huwa sejjaħ għal fuq. 1432 01:05:10,820 --> 01:05:13,027 >> U hekk għal skopijiet ta ' dan pset, int ser 1433 01:05:13,027 --> 01:05:15,860 li ssib li int verament tixtieq li tuża ħafna mill-funzjonijiet li hemm 1434 01:05:15,860 --> 01:05:17,390 fi ħdan il-librerija ctype. 1435 01:05:17,390 --> 01:05:21,040 Biex fuq, biex ibaxxu, huwa fuq, huwa lower-- dawn huma funzjonijiet kollha 1436 01:05:21,040 --> 01:05:24,914 li inti se tkun tista 'tuża ħafna, malajr ħafna fil-kodiċi tiegħek stess li 1437 01:05:24,914 --> 01:05:26,080 ma eżattament dak li dan ma. 1438 01:05:26,080 --> 01:05:28,941 Aħna kiteb out kif jistgħu jikkonvertu string li uppercase. 1439 01:05:28,941 --> 01:05:31,440 Iżda dan huwa effettivament il-kodiċi li xi ħadd ieħor kiteb 1440 01:05:31,440 --> 01:05:33,800 u li inti tista 'aċċess permezz ta 'funzjoni differenti. 1441 01:05:33,800 --> 01:05:34,300 Yeah? 1442 01:05:34,300 --> 01:05:39,570 >> UDJENZA: Allura inti biss kopja A fil hemm u tagħmel dan għal kull ittra waħda? 1443 01:05:39,570 --> 01:05:42,070 >> ANDI Peng: Yeah, minħabba I ma kura dwar il-valuri ta '. 1444 01:05:42,070 --> 01:05:44,540 I biss kura li d-differenza bejniethom huwa 32, id-dritt? 1445 01:05:44,540 --> 01:05:48,210 Id-differenza bejn zghar b u uppercase B huwa wkoll 32. 1446 01:05:48,210 --> 01:05:50,860 U d-differenza bejn c u uppercase C huwa dejjem 32. 1447 01:05:50,860 --> 01:05:53,235 >> I biss għandhom jimpurtak mill- differenza bejn it-tnejn, 1448 01:05:53,235 --> 01:05:56,666 minħabba kollha ta 'l-ittri isegwu l-istess mudell, id-dritt? 1449 01:05:56,666 --> 01:05:58,540 Jekk ikolli id-differenza bejn wieħed minnhom, 1450 01:05:58,540 --> 01:06:01,050 Naf dak id-differenza bejn kull wieħed minnhom huwa. 1451 01:06:01,050 --> 01:06:01,740 Tajba kwistjoni. 1452 01:06:01,740 --> 01:06:04,090 Yeah. 1453 01:06:04,090 --> 01:06:06,660 Kulħadd tajba? 1454 01:06:06,660 --> 01:06:09,080 KOLLOX SEW. 1455 01:06:09,080 --> 01:06:09,580 OOP. 1456 01:06:09,580 --> 01:06:14,380 1457 01:06:14,380 --> 01:06:15,270 >> KOLLOX SEW. 1458 01:06:15,270 --> 01:06:20,310 Allura kunċett ieħor li l- ser tkun utli ħafna kif inti 1459 01:06:20,310 --> 01:06:22,570 tkompli tiżviluppa kodiċi tiegħek huwa din l-idea 1460 01:06:22,570 --> 01:06:25,430 tal-ħolqien funzjonijiet jew estrazzjoni. 1461 01:06:25,430 --> 01:06:28,479 Allura issa dritt, konna kollha meħuda alġebra. 1462 01:06:28,479 --> 01:06:31,770 Fl-alġebra, inti mgħallma li hemm dan ħaġa wunderbare imsejħa funzjoni 1463 01:06:31,770 --> 01:06:35,300 magna, fejn jekk inti input wieħed tip ta 'numru, 1464 01:06:35,300 --> 01:06:38,720 din tmur permezz din il-funzjoni isbaħ u l pops produzzjoni differenti, id-dritt? 1465 01:06:38,720 --> 01:06:42,220 Fil-kodiċi, l-istess ħaġa jiġri fi kwalunkwe tip ta 'funzjoni. 1466 01:06:42,220 --> 01:06:48,230 >> So I tista fiżikament jiktbu fil-ġisem tiegħi tal-kodiċi tiegħi 1467 01:06:48,230 --> 01:06:52,357 dikjarazzjoni prinċipali li attwalment ma tkun xi tkun il-korp tal-kodiċi qed tagħmel. 1468 01:06:52,357 --> 01:06:54,940 Iżda barra minn dan, nista 'wkoll jiktbu funzjonijiet differenti ħafna 1469 01:06:54,940 --> 01:06:56,320 li tagħmel ħafna affarijiet differenti. 1470 01:06:56,320 --> 01:06:58,570 Per eżempju, aħna ħadthom diġà bdew jużaw xi wħud minnhom. 1471 01:06:58,570 --> 01:07:00,610 Printf-- li hija funzjoni li xi ħadd ieħor 1472 01:07:00,610 --> 01:07:02,870 diġà bil-miktub li nistgħu sejħa fil-kodiċi tagħna. 1473 01:07:02,870 --> 01:07:05,410 Biex upper-- f'dan il-każ, upper-- hija funzjoni oħra 1474 01:07:05,410 --> 01:07:07,330 konna bil-miktub li aħna tista 'sejħa fil-kodiċi tagħna. 1475 01:07:07,330 --> 01:07:09,520 U so I raden għaliex aħna anke jkollhom funzjonijiet? 1476 01:07:09,520 --> 01:07:12,100 Għaliex ma aħna biss plop dan kollha fl-istess linja tal-kodiċi? 1477 01:07:12,100 --> 01:07:13,730 Dan jagħmilha aktar faċli għal kulħadd. 1478 01:07:13,730 --> 01:07:19,200 >> Ukoll, ir-raġunament wara li huwa, qabel kollox, l-organizzazzjoni. 1479 01:07:19,200 --> 01:07:21,880 Huwa tassew annoying għaddejjin permezz Kodiċi xi ħadd 1480 01:07:21,880 --> 01:07:25,110 u l-funzjoni waħda simili printf. 1481 01:07:25,110 --> 01:07:28,570 Jekk inti guys attwalment jaf x'inhi l- printf funzjoni involuti tikteb, 1482 01:07:28,570 --> 01:07:30,530 huwa, simili, 1,000 linji ta 'kodiċi. 1483 01:07:30,530 --> 01:07:32,357 >> Jekk kull darba jien ridt li printf xi ħaġa, 1484 01:07:32,357 --> 01:07:35,440 I kellu jikteb 1,000 linji ta 'kodiċi, li jkun verament annoying biex jinqraw, 1485 01:07:35,440 --> 01:07:36,290 id-dritt? 1486 01:07:36,290 --> 01:07:38,860 Dan hu għaliex konna biss ħolqot din il-funzjoni astratt 1487 01:07:38,860 --> 01:07:41,670 li aħna diġà ħadd inkella kitbet x'imkien ieħor. 1488 01:07:41,670 --> 01:07:44,920 U kull darba għandna bżonn li jużawh fl kodiċi tagħna, aħna biss għandhom jgħidu printf. 1489 01:07:44,920 --> 01:07:48,070 U li huwa kapaċi li tuża l-funzjoni xi ħadd ieħor kiteb fil-kodiċi tagħna. 1490 01:07:48,070 --> 01:07:51,020 Dan jagħmilha aktar faċli organizzazzjonalment biex jinqara kodiċi. 1491 01:07:51,020 --> 01:07:53,460 >> It-tieni nett, huwa simplifikazzjoni. 1492 01:07:53,460 --> 01:07:56,750 Hija tissemplifika l-passi għandna li jieħdu biex isolvu problema tagħna. 1493 01:07:56,750 --> 01:07:59,300 Printf, il-funzjonijiet bħall printf, funzjonijiet simili għal ta 'fuq 1494 01:07:59,300 --> 01:08:03,560 huma kollha affarijiet li jippermettu magħna biex jissimplifikaw kodiċi tagħna isfel hekk huwa faċli. 1495 01:08:03,560 --> 01:08:05,830 U l-aħħar ħaġa hija użu mill-ġdid. 1496 01:08:05,830 --> 01:08:08,710 >> Allura l-fatt li għandna funzjoni msejħa printf 1497 01:08:08,710 --> 01:08:11,990 li nistgħu sejħa ħafna differenti ħinijiet u jippermettilha li terġa tkun użata. 1498 01:08:11,990 --> 01:08:14,980 I Jekk kellhom jiktbu printf, I biss jiktbu darba. 1499 01:08:14,980 --> 01:08:16,439 Jeżisti biss f'dak il-post wieħed. 1500 01:08:16,439 --> 01:08:19,890 Jekk jien ridt li tagħmel dan mill-ġdid, nixtieq għandek kopja u paste kollha ta 'dak 1501 01:08:19,890 --> 01:08:21,760 fis-tieni linja tiegħi tal-kodiċi. 1502 01:08:21,760 --> 01:08:24,880 C'est pourquoi jekk noħolqu funzjoni li teżisti barra mill ewlieni tagħna, 1503 01:08:24,880 --> 01:08:26,880 nistgħu biss sejħa lill u użu mill-ġdid kull meta 1504 01:08:26,880 --> 01:08:29,604 għandna bżonn b'tali mod li huwa ħafna aktar faċli għalina bħala programmi li tikteb. 1505 01:08:29,604 --> 01:08:32,220 1506 01:08:32,220 --> 01:08:35,549 >> Allura l-mod li aħna fil-fatt jikteb funzjoni hija simili ħafna, id-dritt? 1507 01:08:35,549 --> 01:08:37,590 Dan huwa tip ta 'l-ewwel eżempju li aħna ser 1508 01:08:37,590 --> 01:08:42,830 tara funzjoni jieħdu fuq stil differenti minn null prinċipali tagħna int. 1509 01:08:42,830 --> 01:08:46,779 F'dan il-każ, jekk jien ridt li jiktbu funzjoni msejħa q, id-dritt? 1510 01:08:46,779 --> 01:08:49,370 >> U l-valur int hawn hija kollha javżak me, 1511 01:08:49,370 --> 01:08:51,649 dak li nixtieq dan funzjoni li jirritornaw għall me? 1512 01:08:51,649 --> 01:08:54,484 Jekk irrid kubu numru sħiħ, Jien ser jridu input. 1513 01:08:54,484 --> 01:08:55,525 Dawn huma l-parametri. 1514 01:08:55,525 --> 01:08:58,490 Jien ser inputs valur ta 'int tip. 1515 01:08:58,490 --> 01:09:01,300 U jien ser jirritorna valur tip ieħor ta 'int. 1516 01:09:01,300 --> 01:09:03,050 U fil hawn, kif inti taraw, kollha qed nagħmel 1517 01:09:03,050 --> 01:09:07,300 huwa cubing tkun xi input tiegħi huwa kif output tiegħi u jirritornaha. 1518 01:09:07,300 --> 01:09:10,790 >> Allura dan kollu funzjoni ma jkun jieħu xi tip ta 'numru sħiħ. 1519 01:09:10,790 --> 01:09:14,979 Hija mmultiplikati minnu stess darbtejn b'mod li kubi fis-seħħ. 1520 01:09:14,979 --> 01:09:17,729 U allura dan jirritorna kwalunkwe li output huwa. 1521 01:09:17,729 --> 01:09:20,540 Allura f'dan il-każ, huwa żewġ linji ta ' kodiċi li kellna biex jiktbu extra. 1522 01:09:20,540 --> 01:09:22,880 Imma jekk ridna li jsejħu fuq dan darba, 1523 01:09:22,880 --> 01:09:26,210 huwa ħafna aktar faċli biex tip li wieħed linja dritt hawn li fil kubu minn 1524 01:09:26,210 --> 01:09:28,830 jkollhom jgħaddu iktar minn darba. 1525 01:09:28,830 --> 01:09:34,180 >> Allura l-mod li essenzjalment kwalunkwe ifformattjar għal kwalunkwe tip ta 'funzjoni 1526 01:09:34,180 --> 01:09:36,420 se jeżistu huwa simili hawn. 1527 01:09:36,420 --> 01:09:38,659 Allura aħna għandna l-isem funzjoni. 1528 01:09:38,659 --> 01:09:39,950 F'dan il-każ, huwa msejjaħ kubu. 1529 01:09:39,950 --> 01:09:42,033 U aħna isem li bih kubu minħabba huwa faċli li wieħed jiftakru. 1530 01:09:42,033 --> 01:09:44,220 Tista 'isem kwadru u dan jista 'attwalment jiġi kubiku. 1531 01:09:44,220 --> 01:09:45,500 Ma jimpurtax. 1532 01:09:45,500 --> 01:09:48,020 Just isem li int assenjazzjoni funzjoni tiegħek. 1533 01:09:48,020 --> 01:09:51,660 >> Dan id-dritt hawn, int, huwa l- tip tal-parametru li għandek bżonn. 1534 01:09:51,660 --> 01:09:54,149 Allura dak li ma din il-funzjoni bżonn sabiex jopera? 1535 01:09:54,149 --> 01:09:55,990 Ukoll, jeħtieġ input. 1536 01:09:55,990 --> 01:09:56,704 I imsemmija hija input. 1537 01:09:56,704 --> 01:09:58,120 Tista 'isem li bih xi trid. 1538 01:09:58,120 --> 01:10:00,500 Imma I bżonn xi ħaġa ta 'int tip. 1539 01:10:00,500 --> 01:10:03,730 Li għaddej biex attwalment tesegwixxi dak kollu li huwa ġewwa hawn, 1540 01:10:03,730 --> 01:10:04,990 il-korp tal-funzjoni. 1541 01:10:04,990 --> 01:10:07,847 U allura l-tip ta 'ritorn dritt hawn, dan int-- 1542 01:10:07,847 --> 01:10:09,680 kollha huwa javżak me huwa li din il-funzjoni huwa 1543 01:10:09,680 --> 01:10:11,250 ser jirritornaw għall lili fil int. 1544 01:10:11,250 --> 01:10:14,460 Allura li għaddej biex tieħu fi int u li għaddej biex jagħtuk lura int. 1545 01:10:14,460 --> 01:10:17,750 Ma kulħadd jifhem kif il- ifformattjar ta 'dan it-tip tax-xogħlijiet? 1546 01:10:17,750 --> 01:10:18,250 Kessaħ. 1547 01:10:18,250 --> 01:10:24,690 1548 01:10:24,690 --> 01:10:25,740 >> KOLLOX SEW. 1549 01:10:25,740 --> 01:10:31,770 Allura ma tkun inkwetat jekk dan jidher dritt astratt ftit issa. 1550 01:10:31,770 --> 01:10:33,450 Din hija xi ħaġa li aħna ser nitkellmu dwar. 1551 01:10:33,450 --> 01:10:36,310 Aħna ser adsa aktar profonda aktar tard fil-kors. 1552 01:10:36,310 --> 01:10:41,170 Il-mod li kull tip ta 'livell ogħla estrazzjoni ta 'dawn l-affarijiet xogħol 1553 01:10:41,170 --> 01:10:43,530 hija li, fil-memorja, fl kompjuter tiegħek, kollox 1554 01:10:43,530 --> 01:10:47,660 hija maħżuna f'dan it-tip tal munzell, għandu I say. 1555 01:10:47,660 --> 01:10:49,070 >> Allura up hemm fil-quċċata. 1556 01:10:49,070 --> 01:10:50,861 I do not know jekk inti guys jista 'jara li tajjeb. 1557 01:10:50,861 --> 01:10:52,590 I ser jippruvaw li zoom. 1558 01:10:52,590 --> 01:10:55,111 Hawn fil-quċċata, aħna jkollhom it-test fiżiku 1559 01:10:55,111 --> 01:10:57,860 ta 'dak il-kompjuter huwa interpreting-- l-żerijiet u dawk li 1560 01:10:57,860 --> 01:10:59,540 jeżistu fi ħdan il-kompjuter tagħna. 1561 01:10:59,540 --> 01:11:03,390 U allura aħna għandna l initialized data u uninitialized data, 1562 01:11:03,390 --> 01:11:05,340 dak li nsejħu varjabbli globali. 1563 01:11:05,340 --> 01:11:08,200 Allura varjabbli li jeżistu fil-programmi kollha 1564 01:11:08,200 --> 01:11:11,815 u madwar tiegħek kollu, essenzjalment, kodiċi. 1565 01:11:11,815 --> 01:11:13,940 Nru inkwiet jekk inti guys huma tip ta 'mhux ċar dwar dan. 1566 01:11:13,940 --> 01:11:16,060 Hija ma verament kwistjoni dritt issa. 1567 01:11:16,060 --> 01:11:18,680 >> U allura għandna x'hemm imsejħa borġ fi munzell. 1568 01:11:18,680 --> 01:11:21,140 Aħseb ta 'ċumnija litteralment bħala bħad munzell ta 'affarijiet, 1569 01:11:21,140 --> 01:11:23,098 munzell ta 'differenti affarijiet jiġu mbuttati fuq nett 1570 01:11:23,098 --> 01:11:27,870 ta 'xulxin li jaħżnu d-diversi varjabbli u sintassi fi ħdan kodiċi tiegħek. 1571 01:11:27,870 --> 01:11:31,460 U allura hawnhekk fil-qiegħ nett, aħna għandna l-varjabbli ambjent 1572 01:11:31,460 --> 01:11:35,480 ta 'dak li qed jeżegwixxi fis biss linja tiegħek ftit tal-kodiċi. 1573 01:11:35,480 --> 01:11:40,510 >> U aħna qed biss ser zoom fuq il-parti attwali munzell. 1574 01:11:40,510 --> 01:11:43,880 Allura dritt hawn, jekk konna biex zoom fuq biss f'dan il-qasam tal-munzell, 1575 01:11:43,880 --> 01:11:45,140 dan huwa dak li jidher qisu. 1576 01:11:45,140 --> 01:11:48,590 U dan huwa attwalment pretty importanti meta inti guys jitkellmu dwar il-funzjonijiet, 1577 01:11:48,590 --> 01:11:52,330 minħabba avviż li l- memorja tal-kompjuter tiegħek 1578 01:11:52,330 --> 01:11:55,600 huwa ħażna tal-fatturi varjabbli u l-funzjonijiet 1579 01:11:55,600 --> 01:11:58,790 u l-parametri ta 'kemm tiegħek funzjoni u l-varjabbli prinċipali tiegħek 1580 01:11:58,790 --> 01:12:00,190 f'postijiet differenti. 1581 01:12:00,190 --> 01:12:03,390 >> Allura issa dritt, prinċipali hija il-funzjoni proprja 1582 01:12:03,390 --> 01:12:04,780 li int eżekuzzjoni f'kodiċi. 1583 01:12:04,780 --> 01:12:08,050 Inti għandek parametri tagħha maħżuna hawn u l-varjabbli lokali tiegħu maħżun hawnhekk. 1584 01:12:08,050 --> 01:12:12,270 Varjabbli lokali biss tfisser kull varjabbli li jeżistu biss fi ħdan dik il-funzjoni. 1585 01:12:12,270 --> 01:12:15,610 U fuq quċċata ta 'dan, għandek din funzjoni separata ta imsejħa kubu. 1586 01:12:15,610 --> 01:12:18,240 Inti għandek li l-parametri kif ukoll dawk lokal. 1587 01:12:18,240 --> 01:12:21,540 >> U r-raġuni tista tara hawnhekk huwa li dak li 1588 01:12:21,540 --> 01:12:25,030 jiġri meta kubu ittieħdet fi valur mill-funzjoni prinċipali tiegħek 1589 01:12:25,030 --> 01:12:27,640 hija li fil-fatt huwa ikkupjar li aktar. 1590 01:12:27,640 --> 01:12:31,470 Mela jekk jien ridt li kubu 2 u r-ritorn 8, li 2 1591 01:12:31,470 --> 01:12:33,730 huwa attwalment inputted bħala parametru u huwa 1592 01:12:33,730 --> 01:12:37,690 kkupjati fuq sabiex ikollok it eżistenti f'żewġ postijiet differenti fil-memorja. 1593 01:12:37,690 --> 01:12:40,520 U inti għandek tkun attent ħafna fuq ftakar liema waħda minn dawk 1594 01:12:40,520 --> 01:12:42,520 int fil-fatt manipulazzjoni. 1595 01:12:42,520 --> 01:12:47,170 U eżempju ta 'dak li ġara li jkun ħafna, ħażina ħafna 1596 01:12:47,170 --> 01:12:48,050 jeżisti dritt hawn. 1597 01:12:48,050 --> 01:12:50,760 1598 01:12:50,760 --> 01:12:58,650 >> Allura dritt hawn, jien qbilna, fit-teorija, programm dritt hawn, funzjoni ewlenija 1599 01:12:58,650 --> 01:13:02,180 li jien iddikjarat li int x ugwali 1. 1600 01:13:02,180 --> 01:13:04,505 Jien tiddikjara y ieħor int ugwali 2. 1601 01:13:04,505 --> 01:13:06,380 U allura niġri it permezz ta 'din il-funzjoni 1602 01:13:06,380 --> 01:13:09,647 imsejħa tpartit, fejn I jassumi li huwa iskambji taż-żewġ valuri. 1603 01:13:09,647 --> 01:13:11,480 U allura jien ser tipprintjahom, id-dritt? 1604 01:13:11,480 --> 01:13:13,220 Dak hu li nixtieq dan il-programm li tagħmel. 1605 01:13:13,220 --> 01:13:15,180 >> Mela ejja tinżel u tagħti ħarsa. 1606 01:13:15,180 --> 01:13:18,200 Mela jekk I attwalment jiktbu differenti funzjoni, kif tistgħu taraw, 1607 01:13:18,200 --> 01:13:19,750 għandna funzjoni prinċipali tagħna hawn. 1608 01:13:19,750 --> 01:13:22,860 U allura għandna tagħna tieni funzjoni hawn. 1609 01:13:22,860 --> 01:13:24,520 Tpartit nulli. 1610 01:13:24,520 --> 01:13:27,090 Null ifisser biss li huwa mhux ser jirritornaw xejn. 1611 01:13:27,090 --> 01:13:28,930 L-isem funzjoni hija imsejħa tpartit, u huwa 1612 01:13:28,930 --> 01:13:33,730 ser konsum żewġ varjabbli, int a u int b, minn tiegħek [inaudible] funzjoni. 1613 01:13:33,730 --> 01:13:39,010 >> Allura essenzjalment fil hawn, aħna qed tgħaddi x uy fis din il-funzjoni. 1614 01:13:39,010 --> 01:13:40,760 U jekk konna biex joħolqu this-- hekk irridu 1615 01:13:40,760 --> 01:13:42,420 biex joħolqu valur temporanju, id-dritt? 1616 01:13:42,420 --> 01:13:43,930 Aħna qed tmur biex tassenja dak li a. 1617 01:13:43,930 --> 01:13:45,388 U mbagħad se issa ugwali b. 1618 01:13:45,388 --> 01:13:47,660 U b se tkun lura fejn il-valur temperatura kien, 1619 01:13:47,660 --> 01:13:51,070 li huwa, għaliex meta inti tixtieq li tpartit affarijiet, 1620 01:13:51,070 --> 01:13:52,320 inti ma tistax biss nixtieq tpartit lilhom. 1621 01:13:52,320 --> 01:13:54,360 >> Int għandek iżżomm out waħda hawn hekk li jiftakar 1622 01:13:54,360 --> 01:13:56,485 dak li huwa, għaliex ladarba inti tpartit waħda, tinsa 1623 01:13:56,485 --> 01:13:58,200 dak li l-valur oriġinali kien, right? 1624 01:13:58,200 --> 01:14:00,990 Allura fit-teorija, dan il-programm għandhom jaħdmu, id-dritt? 1625 01:14:00,990 --> 01:14:03,630 Jekk jien ridt li tpartit l- tnejn, huma għandhom tpartit. 1626 01:14:03,630 --> 01:14:05,490 Mela ejja run u tara jekk din taħdem. 1627 01:14:05,490 --> 01:14:11,130 1628 01:14:11,130 --> 01:14:16,940 >> Allura kif inti guys tista 'tara, x darba 1 kien u y darba kien 2. 1629 01:14:16,940 --> 01:14:21,475 U jekk jien ipprintjaha, x għadu 1 u y hija 2. 1630 01:14:21,475 --> 01:14:25,970 Hmm, dan il-programm ma jidhirx li taħdem il-mod li nixtieq li taħdem. 1631 01:14:25,970 --> 01:14:29,950 Hawn xi ħadd li tixtieq li tieħu xi sparatura fil guessing għaliex dan kien qed jiġri? 1632 01:14:29,950 --> 01:14:34,430 Hija għandha tagħmel il-mod li l-affarijiet differenti huma 1633 01:14:34,430 --> 01:14:38,172 maħżuna f'diversi mkejjen fil-memorja. 1634 01:14:38,172 --> 01:14:39,377 >> KOLLOX SEW. 1635 01:14:39,377 --> 01:14:41,960 Allura inti guys ma jkollhomx għalfejn tinkwieta wisq dwar dan id-dritt issa. 1636 01:14:41,960 --> 01:14:46,610 Iżda nafu li s kubu lokali varjabbli kienu aub, 1637 01:14:46,610 --> 01:14:49,230 għaliex hawnhekk fil-funzjoni tagħna, konna ddikjarat aub 1638 01:14:49,230 --> 01:14:53,570 bħala l-varjabbli li jeżistu fi ħdan kubu, dik il-funzjoni. 1639 01:14:53,570 --> 01:14:59,490 Imma kif tista 'tara, il-parametri li huwa jieħu fil, jiġu maħżuna hawn. 1640 01:14:59,490 --> 01:15:01,370 Iżda aħna ma kinux fil-fatt jirritornaw xejn. 1641 01:15:01,370 --> 01:15:03,120 Aħna ma kienu attwalment qed jinbidlu x uy. 1642 01:15:03,120 --> 01:15:04,440 Konna biss tibdil ta 'u b. 1643 01:15:04,440 --> 01:15:08,340 >> Kellna kkupjati x uy fis xi ħaġa imsejħa u b. 1644 01:15:08,340 --> 01:15:11,092 Imma fil-fatt aħna qatt manipulati x uy infushom. 1645 01:15:11,092 --> 01:15:12,800 Huma inti guys jaraw kif dan qed jiġri? 1646 01:15:12,800 --> 01:15:16,140 Hija li konna sempliċiment kkupjata fuq, iżda aħna ma attwalment miżmuma 1647 01:15:16,140 --> 01:15:18,030 kont ta 'fejn kienu fil-memorja. 1648 01:15:18,030 --> 01:15:20,127 >> U hekk issa l-kompjuter qed tfittex, oh, stajt 1649 01:15:20,127 --> 01:15:21,960 run dan il-ħaġa permezz din il-funzjoni sabiħ. 1650 01:15:21,960 --> 01:15:23,690 Iżda xuy għadhom xuy. 1651 01:15:23,690 --> 01:15:26,240 Xejn ġara minnhom minħabba l-fatt 1652 01:15:26,240 --> 01:15:28,340 li dawk il-parametri u varjabbli lokali 1653 01:15:28,340 --> 01:15:30,150 huma maħżuna differenti post fil-memorja. 1654 01:15:30,150 --> 01:15:32,030 U dan huwa ta 'livell ogħla kunċett li aħna ser 1655 01:15:32,030 --> 01:15:34,300 tibda tara aktar tard fil-kors. 1656 01:15:34,300 --> 01:15:36,950 Iżda biss taf li dan huwa problema li jista 'jiġri 1657 01:15:36,950 --> 01:15:41,400 u li aħna ser insemmu modi dwar kif jittrattaw dan aktar tard fil-kors. 1658 01:15:41,400 --> 01:15:41,900 KOLLOX SEW. 1659 01:15:41,900 --> 01:15:47,750 1660 01:15:47,750 --> 01:15:48,250 Kull dritt. 1661 01:15:48,250 --> 01:15:51,780 Allura l-aħħar kunċett aħna qed verament se tkopri 1662 01:15:51,780 --> 01:15:53,880 li għaddej biex tkun utli għall-pset din il-ġimgħa 1663 01:15:53,880 --> 01:15:56,060 huma liema huma msejħa argumenti kmand linja. 1664 01:15:56,060 --> 01:16:00,820 Allura Rob fil lecture tiegħu għaddiet tip ta 'qosor dwar kif jaħdmu dawn. 1665 01:16:00,820 --> 01:16:02,770 Essenzjalment jafu li meta int bil-miktub 1666 01:16:02,770 --> 01:16:06,280 bħal funzjoni prinċipali, meta aħna kiteb funzjonijiet qabel fil-passat, 1667 01:16:06,280 --> 01:16:07,804 kellna null prinċipali int. 1668 01:16:07,804 --> 01:16:10,470 U r-raġuni kellna nulli hemm kien għaliex programmi tagħna ma 1669 01:16:10,470 --> 01:16:12,520 jeħtieġ li l-valuri input jiddekorri, right? 1670 01:16:12,520 --> 01:16:16,020 Meta I dam Mario, I ma kellhomx bżonn li attwalment biss it-tip fil xi ħaġa 1671 01:16:16,020 --> 01:16:16,970 meta I dam Mario. 1672 01:16:16,970 --> 01:16:20,170 I tista 'twassal lill-utent aktar tard. 1673 01:16:20,170 --> 01:16:22,450 Iżda dan mhux dejjem ikun il-każ. 1674 01:16:22,450 --> 01:16:24,980 >> Per eżempju, f'dan il- problema ġimgħa settijiet, 1675 01:16:24,980 --> 01:16:28,365 int ser jiġi mistoqsi li, Minbarra għall-ispejjeż kurrenti program tiegħek, 1676 01:16:28,365 --> 01:16:30,990 int tmur jridu input ċerti affarijiet fil dritta kif inti 1677 01:16:30,990 --> 01:16:32,050 run program tiegħek. 1678 01:16:32,050 --> 01:16:34,720 Allura l-mod kif nagħmlu li tissejjaħ argument linja tal-kmand, li 1679 01:16:34,720 --> 01:16:37,280 hija bħal argument inti tista 'input direttament 1680 01:16:37,280 --> 01:16:39,260 kif int tipprova tmexxi programm tiegħek. 1681 01:16:39,260 --> 01:16:44,680 >> Allura l-notazzjoni għal dan, huwa pjuttost kumplessi tħares, 1682 01:16:44,680 --> 01:16:47,320 imma huwa verament mhux li diffiċli. Allura int main-- 1683 01:16:47,320 --> 01:16:48,910 li jinsab biss funzjoni prinċipali tiegħek. 1684 01:16:48,910 --> 01:16:52,110 Fis virgola argc parentesi ARGV sekwenza. 1685 01:16:52,110 --> 01:16:56,040 Allura dak kollu li kien qal huwa li dan int argc-- dak kollu li tghidlek 1686 01:16:56,040 --> 01:17:00,560 hija li dawk huma n-numru ta ' argumenti tal-kompjuter għandu jistenna. 1687 01:17:00,560 --> 01:17:03,130 >> Allura ħaġa waħda li tassew importanti li jżommu rekord ta 1688 01:17:03,130 --> 01:17:07,080 huwa l-isem fiżika tal-programm tiegħek jgħodd bħala wieħed minn dawk l-argumenti. 1689 01:17:07,080 --> 01:17:11,080 Mela jekk jien ridt li jkollhom programm tiegħi run plus wieħed linja tal-kmand addizzjonali 1690 01:17:11,080 --> 01:17:13,310 argument, jien attwalment ser ikollhom tnejn. 1691 01:17:13,310 --> 01:17:15,080 Argc attwalment se tkun tnejn. 1692 01:17:15,080 --> 01:17:18,010 U mbagħad string ARGV bracket-- dak kollu li qed tagħmel, 1693 01:17:18,010 --> 01:17:20,410 huwa jagħti me firxa ta 'kordi li l- 1694 01:17:20,410 --> 01:17:24,870 ser biss wiri u jaħżnu dak kollha dawn l-argumenti kmand linja huma. 1695 01:17:24,870 --> 01:17:34,090 >> Għalhekk, per eżempju, jekk jien ridt li jkollhom din programm, ./copy infile outfile, id-dritt? 1696 01:17:34,090 --> 01:17:37,330 Li jinsab biss kmand tipiku Linux. 1697 01:17:37,330 --> 01:17:38,830 X'inhu dak li attwalment hu argc? 1698 01:17:38,830 --> 01:17:41,320 Kemm argumenti kmand linja hemm attwalment f'dan? 1699 01:17:41,320 --> 01:17:45,130 Dan kollu ma huwa jagħmel kopja ta ' l infile 'l-isem tal-fajl wieħed 1700 01:17:45,130 --> 01:17:47,070 u it kopji fis fajl ieħor, id-dritt? 1701 01:17:47,070 --> 01:17:48,700 Li dan kollu qed tagħmel. 1702 01:17:48,700 --> 01:17:53,080 Kif tistgħu taraw, jien tagħmel dan fuq linja waħda mingħajr ma attwalment bżonn il-programm. 1703 01:17:53,080 --> 01:17:55,380 >> X'inhu argc tagħna f'dan il-każ? 1704 01:17:55,380 --> 01:17:58,968 Kemm argumenti għandna? 1705 01:17:58,968 --> 01:17:59,634 UDJENZA: Tliet? 1706 01:17:59,634 --> 01:18:01,200 ANDI Peng: Aħna tlieta, eżattament. 1707 01:18:01,200 --> 01:18:05,030 Allura huwa ħafna intuwittivi biex biss jaħsbu li huwa biss 1708 01:18:05,030 --> 01:18:06,290 l infile u l outfile. 1709 01:18:06,290 --> 01:18:10,190 Iżda nafu li l-isem fiżika tal- programm int taħdem għadd bħala wieħed. 1710 01:18:10,190 --> 01:18:13,220 Allura f'dan il-każ, argc huwa attwalment tlieta. 1711 01:18:13,220 --> 01:18:15,860 Kif dwar, dak li huwa ARGV 0? 1712 01:18:15,860 --> 01:18:18,180 Ftakar, kollha tal- argumenti kmand linja 1713 01:18:18,180 --> 01:18:20,500 kienu maħżuna fil-firxa ta 'spag. 1714 01:18:20,500 --> 01:18:24,140 Mela jekk jien jippruvaw li jkollhom aċċess għaliha, liema ikun ARGV bracket 0 jagħtu me? 1715 01:18:24,140 --> 01:18:25,364 >> UDJENZA: [inaudible]. 1716 01:18:25,364 --> 01:18:26,155 ANDI Peng: Eżattament. 1717 01:18:26,155 --> 01:18:28,550 Ikun agħtini l-dot slash kopja, minħabba li l 1718 01:18:28,550 --> 01:18:31,070 l-element 0, il- ewwel element ta 'firxa tiegħi. 1719 01:18:31,070 --> 01:18:33,236 What about ARGV 1? 1720 01:18:33,236 --> 01:18:33,945 >> UDJENZA: Infile. 1721 01:18:33,945 --> 01:18:35,070 ANDI Peng: Infile, eżattament. 1722 01:18:35,070 --> 01:18:36,272 What about ARGV 2? 1723 01:18:36,272 --> 01:18:37,022 UDJENZA: Outfile. 1724 01:18:37,022 --> 01:18:38,190 ANDI Peng: Outfile. 1725 01:18:38,190 --> 01:18:39,290 Dan huwa daqsxejn delikata issa. 1726 01:18:39,290 --> 01:18:42,630 What do you guys think ARGV 3 se tkun tajtu lili 1727 01:18:42,630 --> 01:18:45,522 jekk I ppruvaw li jistampaw li minn? 1728 01:18:45,522 --> 01:18:48,260 >> UDJENZA: [inaudible]? 1729 01:18:48,260 --> 01:18:50,164 >> ANDI Peng: Kellek idejn up? 1730 01:18:50,164 --> 01:18:50,663 Yeah. 1731 01:18:50,663 --> 01:18:51,550 >> UDJENZA: Alternattiva. 1732 01:18:51,550 --> 01:18:52,341 >> ANDI Peng: Eżattament. 1733 01:18:52,341 --> 01:18:55,440 Mela ftakar fil lecture li aħna jkollhom fl-aħħar ta xi ħaġa razza 1734 01:18:55,440 --> 01:18:56,640 imsejħa terminatur null? 1735 01:18:56,640 --> 01:18:58,890 Aħna ser jsibu rwieħhom dan ukoll aktar 'il quddiem fil-klassi. 1736 01:18:58,890 --> 01:19:02,472 Iżda nafu li notazzjoni, il-mod tal-kompjuter tiegħek 1737 01:19:02,472 --> 01:19:04,430 jaf li huwa l-aħħar tal-firxa huwa li 1738 01:19:04,430 --> 01:19:07,310 tpoġġi xi ħaġa imsejħa null terminatur jew sing żero. 1739 01:19:07,310 --> 01:19:12,047 >> Mela jekk inti tipprova l-aċċess ARGV 3, int ser jintlaqtu dan sing 0. 1740 01:19:12,047 --> 01:19:13,630 Dan huwa saħansitra aktar ta 'kwistjoni trick. 1741 01:19:13,630 --> 01:19:17,020 What about ARGV 4? 1742 01:19:17,020 --> 01:19:20,920 Allura dan huwa terminatur null passat, passat il-limiti ta 'firxa tagħna. 1743 01:19:20,920 --> 01:19:24,380 What do you think se jiġri meta aħna tipprova tagħmel dan? 1744 01:19:24,380 --> 01:19:25,842 >> UDJENZA: [inaudible]? 1745 01:19:25,842 --> 01:19:26,550 ANDI Peng: Jiddispjacini? 1746 01:19:26,550 --> 01:19:28,025 Jgħidu li ftit louder? 1747 01:19:28,025 --> 01:19:29,086 >> UDJENZA: [inaudible]. 1748 01:19:29,086 --> 01:19:29,710 ANDI Peng: Iva. 1749 01:19:29,710 --> 01:19:32,420 Dan huwa l-isem tal- qasam tkun taf aktar probabbli tikseb. 1750 01:19:32,420 --> 01:19:36,610 Iżda nafu li ARGV 4-- li jippermettilek li aċċess 1751 01:19:36,610 --> 01:19:38,610 postijiet fil-kompjuter tiegħek memorja li int verament 1752 01:19:38,610 --> 01:19:41,650 m'għandux ikun jmissu, minħabba dritt issa inti taf liema ARGV huwa. 1753 01:19:41,650 --> 01:19:46,220 Inti taf li huwa firxa ta 'daqs 3 li għandha kopja dot, infile u outfile. 1754 01:19:46,220 --> 01:19:50,200 >> Jekk inti tipprova tmur s'issa lil hinn minn dik li int passat l-terminatur null, 1755 01:19:50,200 --> 01:19:53,050 kompjuter tiegħek probabbilment xi ħaġa maħżuna ARGV 4. 1756 01:19:53,050 --> 01:19:55,790 U int verament ma għandu jkun jingħataw aċċess għal ARGV 4, 1757 01:19:55,790 --> 01:19:58,130 għaliex għandek fajl kabinett u int biss 1758 01:19:58,130 --> 01:19:59,790 jingħataw aċċess għal dawk it-tliet ixkafef. 1759 01:19:59,790 --> 01:20:02,870 Imma jekk inti tipprova tilħaq lil hinn mill l-ixkaffa ta 'fejn inti huma permessi, 1760 01:20:02,870 --> 01:20:04,930 int ser tibda messing mal affarijiet oħra fil-memorja tal-kompjuter tiegħek. 1761 01:20:04,930 --> 01:20:06,690 Li għaddej biex tkun tassew, tassew ħżiena. 1762 01:20:06,690 --> 01:20:07,440 Hekk biss jafu li. 1763 01:20:07,440 --> 01:20:10,370 Oqgħod attent ħafna li inti ma biss saltwarjament jibdew 1764 01:20:10,370 --> 01:20:14,772 aċċess elementi fil-firxa li ma kinux fil dak li riedu joħolqu. 1765 01:20:14,772 --> 01:20:17,114 Yep. 1766 01:20:17,114 --> 01:20:18,430 >> KOLLOX SEW. 1767 01:20:18,430 --> 01:20:26,360 Allura aħna qed tmur biex tagħmel ieħor eżempju terminal hawn. 1768 01:20:26,360 --> 01:20:27,300 KOLLOX SEW. 1769 01:20:27,300 --> 01:20:29,900 Allura Rob malajr fil lecture l-oħra jum marru 1770 01:20:29,900 --> 01:20:35,040 permezz ta 'dan eżempju, fejn hu kellhom int ARGV int prinċipali string argc 1771 01:20:35,040 --> 01:20:39,090 parentesi, li huwa javżak me li jien ser ikollhom argumenti linja ta 'kmand. 1772 01:20:39,090 --> 01:20:41,860 >> Huwa għandu, jekk argc ugwali ugwali 2-- ftakar, 1773 01:20:41,860 --> 01:20:45,070 ugwali ugwali jfisser paragun. 1774 01:20:45,070 --> 01:20:47,980 Jekk tkun ugwali 2, allura jien morna għall-istampa hello, 1775 01:20:47,980 --> 01:20:51,190 ikun x'ikun l-ewwel element tad-firxa hija. 1776 01:20:51,190 --> 01:20:54,100 Print Else, bonjour dinja. 1777 01:20:54,100 --> 01:20:56,300 X'inhu dan se jiġri essenzjalment? 1778 01:20:56,300 --> 01:21:00,570 Jista xi ħadd biss tispjega fid Ingliż dak dan il-programm qed tagħmel? 1779 01:21:00,570 --> 01:21:01,272 Yeah. 1780 01:21:01,272 --> 01:21:08,160 >> UDJENZA: Jekk xi ħadd ittajpjat fil-kmand u qal ewwel u l-aħħar isem tagħhom, 1781 01:21:08,160 --> 01:21:12,096 dan mhux biss se jistampaw il- ewwel waħda u jgħidu, hello, 1782 01:21:12,096 --> 01:21:14,090 tkun xi tkun l-ewwel isem tiegħek huwa. 1783 01:21:14,090 --> 01:21:15,410 >> ANDI Peng: OK, ejja run. 1784 01:21:15,410 --> 01:21:22,470 Għalhekk, per eżempju, jekk I kellhom jagħmlu dan il-fajl jagħmlu bonjour to-- bonjour 1785 01:21:22,470 --> 01:21:24,500 to-- dak li tridu lili biex input? 1786 01:21:24,500 --> 01:21:25,900 >> UDJENZA: L-ewwel u l-aħħar isem. 1787 01:21:25,900 --> 01:21:27,280 >> ANDI Peng: L-ewwel u l-aħħar isem? 1788 01:21:27,280 --> 01:21:28,180 Spazji? 1789 01:21:28,180 --> 01:21:29,690 >> UDJENZA: Yeah. 1790 01:21:29,690 --> 01:21:33,490 >> ANDI Peng: Jista 'xi ħadd tell me dritt issa, dak li huwa argc? 1791 01:21:33,490 --> 01:21:35,630 Just hemm dritt? 1792 01:21:35,630 --> 01:21:36,290 Oops, sorry. 1793 01:21:36,290 --> 01:21:37,920 Let me jmorru lura. 1794 01:21:37,920 --> 01:21:40,740 Kemm argumenti kmand linja are-- inti guys ma tistax verament tara. 1795 01:21:40,740 --> 01:21:43,760 Imma jien ser jippruvaw li zoom. 1796 01:21:43,760 --> 01:21:44,290 Qed nipprova. 1797 01:21:44,290 --> 01:21:45,414 Yeah, hemm tlieta, id-dritt? 1798 01:21:45,414 --> 01:21:48,750 Huwa dot mmejla hello, huwa Andi, u huwa Peng. 1799 01:21:48,750 --> 01:21:51,870 >> Allura dak li inti guys think dan programm se tkun l-istampar out? 1800 01:21:51,870 --> 01:21:55,550 1801 01:21:55,550 --> 01:21:56,060 Oh. 1802 01:21:56,060 --> 01:21:57,120 Oh, sorry. 1803 01:21:57,120 --> 01:21:57,810 Isem ħażin. 1804 01:21:57,810 --> 01:22:03,630 1805 01:22:03,630 --> 01:22:06,130 Huwa istampar out, bonjour dinja. 1806 01:22:06,130 --> 01:22:09,603 Hawn xi ħadd li tixtieq li jispjegaw għaliex dak li qed jiġri? 1807 01:22:09,603 --> 01:22:10,103 Yeah? 1808 01:22:10,103 --> 01:22:11,019 >> UDJENZA: [inaudible]. 1809 01:22:11,019 --> 01:22:14,439 1810 01:22:14,439 --> 01:22:15,230 ANDI Peng: Eżattament. 1811 01:22:15,230 --> 01:22:19,940 Allura hawnhekk, huma kondizzjonali huwa, jekk argc ugwali ugwali 2. 1812 01:22:19,940 --> 01:22:23,650 Allura biss fil-każ li hemm żewġ argumenti kmand linja. 1813 01:22:23,650 --> 01:22:25,850 Imbagħad jien ser jistampaw, hello, tkun xi tkun. 1814 01:22:25,850 --> 01:22:28,210 Imma inkella, jien ser print biss, bonjour dinja. 1815 01:22:28,210 --> 01:22:30,040 Allura ma xi ħadd jridu li tagħti me eżempju 1816 01:22:30,040 --> 01:22:35,050 ta 'kif I se jkunu jistgħu attwalment ġġibu li jistampaw il-valur tal ARGV 1? 1817 01:22:35,050 --> 01:22:38,600 >> X'għandu I għandhom input hawn? 1818 01:22:38,600 --> 01:22:39,840 Biss ħaġa waħda, id-dritt? 1819 01:22:39,840 --> 01:22:42,900 Minħabba li l-dot bonjour diġà jgħodd bħala l-ewwel argument. 1820 01:22:42,900 --> 01:22:43,930 I biss jkollhom waħda aktar. 1821 01:22:43,930 --> 01:22:46,470 Mela dot bonjour jekk I biss ma Andi. 1822 01:22:46,470 --> 01:22:47,270 Hello, Andi. 1823 01:22:47,270 --> 01:22:49,186 Ma kulħadd jifhem għaliex dak li qed jiġri? 1824 01:22:49,186 --> 01:22:49,602 Yeah. 1825 01:22:49,602 --> 01:22:52,500 >> UDJENZA: Allura l-ispazju bejn il- line-- kmand huwa [inaudible]? 1826 01:22:52,500 --> 01:22:56,247 1827 01:22:56,247 --> 01:22:56,830 ANDI Peng: Le 1828 01:22:56,830 --> 01:23:03,810 Allura l-ispazju fil-linja ta 'kmand argument, x, li tgħid kompjuter tiegħek 1829 01:23:03,810 --> 01:23:06,820 li dan huwa l-bidu ta 'sekwenza ġdida. 1830 01:23:06,820 --> 01:23:11,130 Allura ARGV string here-- it ħwienet kollha ta 'kmandi argumenti tiegħek linja 1831 01:23:11,130 --> 01:23:13,110 f'qatet. 1832 01:23:13,110 --> 01:23:17,420 U għalhekk l-ispazju fil-linja tal-kmand argument-- dak kollu li ma huwa jgħidlek, 1833 01:23:17,420 --> 01:23:21,030 dan huwa fl-aħħar tal sekwenza waħda u wasal iż-żmien li wieħed jgħaddi għall-ieħor. 1834 01:23:21,030 --> 01:23:21,990 >> Yeah. 1835 01:23:21,990 --> 01:23:23,530 Dan huwa pretty importanti għall pset tiegħek, għax int 1836 01:23:23,530 --> 01:23:24,613 ser jiġu ittestjar dawn. 1837 01:23:24,613 --> 01:23:29,300 Allura ħadd ma jkollu xi mistoqsijiet dwar dan? 1838 01:23:29,300 --> 01:23:30,016 OK, berred. 1839 01:23:30,016 --> 01:23:30,515 Yeah? 1840 01:23:30,515 --> 01:23:35,008 >> UDJENZA: Allura r-raġuni inti tpoġġi numru sħiħ argument calc minflok 1841 01:23:35,008 --> 01:23:40,059 ta [inaudible] ikun meta inti tixtieq tip informazzjoni addizzjonali lill 1842 01:23:40,059 --> 01:23:41,030 [Inaudible]? 1843 01:23:41,030 --> 01:23:42,090 >> ANDI Peng: Yeah, eżattament. 1844 01:23:42,090 --> 01:23:45,370 Xi programmi se jeħtieġu li inti għall-input argument linja ta 'kmand 1845 01:23:45,370 --> 01:23:47,732 li tgħaddi fi u li tuża dak. 1846 01:23:47,732 --> 01:23:49,035 Yeah. 1847 01:23:49,035 --> 01:23:50,410 UDJENZA: Allura dak li jekk [inaudible]? 1848 01:23:50,410 --> 01:23:55,440 1849 01:23:55,440 --> 01:23:58,870 >> ANDI Peng: Well, dak għandi għall-bidla imbagħad fil-programm tiegħi? 1850 01:23:58,870 --> 01:23:59,870 >> UDJENZA: Just 3. 1851 01:23:59,870 --> 01:24:12,460 1852 01:24:12,460 --> 01:24:15,020 >> ANDI Peng: Għaliex huwa li jiġri, taħseb? 1853 01:24:15,020 --> 01:24:18,940 >> UDJENZA: Minħabba li l-[inaudible]. 1854 01:24:18,940 --> 01:24:22,370 >> UDJENZA: Youd għandek bidla li 2 [inaudible]. 1855 01:24:22,370 --> 01:24:23,484 >> UDJENZA: 1 u 2. 1856 01:24:23,484 --> 01:24:24,650 ANDI Peng: 1 u 2, eżattament. 1857 01:24:24,650 --> 01:24:29,150 Allura f'dan il-każ, inti probabilment tixtieq li jkollok żewġ printf statements-- 1858 01:24:29,150 --> 01:24:32,601 wieħed li stampati ARGV 1 u il-wieħed li stampat ARGV 2. 1859 01:24:32,601 --> 01:24:33,100 Hawnhekk. 1860 01:24:33,100 --> 01:24:34,516 I jistgħu attwalment jagħmlu dan malajr reali. 1861 01:24:34,516 --> 01:24:46,720 1862 01:24:46,720 --> 01:24:47,320 Hemm inti tmur. 1863 01:24:47,320 --> 01:24:48,287 Oh. 1864 01:24:48,287 --> 01:24:49,370 Mhux pjuttost dak li riedu. 1865 01:24:49,370 --> 01:24:52,590 Imma jekk inti guys mess mal-madwar l-ifformattjar, se toħroġ. 1866 01:24:52,590 --> 01:24:54,981 Yeah. 1867 01:24:54,981 --> 01:24:55,480 Kessaħ. 1868 01:24:55,480 --> 01:24:57,670 Naf aħna qed daqsxejn qasir fil-ħin. 1869 01:24:57,670 --> 01:25:02,469 Imma jien biss se malajr jonfqu ftit minuti għaddejjin helpful-- 1870 01:25:02,469 --> 01:25:03,760 UDJENZA: Għandek żewġ minuti. 1871 01:25:03,760 --> 01:25:05,010 ANDI Peng: Għandi żewġ minuti? 1872 01:25:05,010 --> 01:25:06,340 Grazzi. 1873 01:25:06,340 --> 01:25:09,180 Xi tips pset malajr. 1874 01:25:09,180 --> 01:25:13,100 Allura għal dan pset, I jirrakkomanda ħafna, bħal I said, kulħadd biex taqra l-spec. 1875 01:25:13,100 --> 01:25:16,804 Int ser tkun bil-miktub tlieta wieħed programs-- imsejħa initials.c, wieħed imsejjaħ caesar.c, 1876 01:25:16,804 --> 01:25:17,720 wieħed imsejjaħ vigenere.c. 1877 01:25:17,720 --> 01:25:20,465 1878 01:25:20,465 --> 01:25:22,340 Xi tips importanti li inti guys verament irridu 1879 01:25:22,340 --> 01:25:25,040 li wieħed iżomm mind-- hekk hemm din il-funzjoni 1880 01:25:25,040 --> 01:25:27,770 imsejħa atoi-- kif Jien inħobb ngħid, a trois. 1881 01:25:27,770 --> 01:25:29,520 Ċar jekk dan huwa attwalment kif inti jgħidu li din. 1882 01:25:29,520 --> 01:25:32,510 Iżda dan kollu qed jagħmel, huwa inputjar. 1883 01:25:32,510 --> 01:25:34,320 Hija tikkonverti string għal int. 1884 01:25:34,320 --> 01:25:37,490 Allura tirrappreżenta ASCII li i numru sħiħ. 1885 01:25:37,490 --> 01:25:40,310 Huwa biss jikkonvertu ASCII valuri li Integer valuri. 1886 01:25:40,310 --> 01:25:44,510 Mela ftakar ARGV, il-firxa li l-ħażniet kollha ta 'jikkmanda tiegħek linja arguments-- 1887 01:25:44,510 --> 01:25:46,300 huwa jaħżen kollha bħala kordi. 1888 01:25:46,300 --> 01:25:50,010 U hekk jekk inti tixtieq li tkun tista ' jkollhom waħda minnhom issir integer, 1889 01:25:50,010 --> 01:25:52,750 int ser ikollhom li tuża dan il-valur hawnhekk. 1890 01:25:52,750 --> 01:25:56,690 >> Modulo, bħal aħna koperti kmieni fil-klassi llum, 1891 01:25:56,690 --> 01:25:59,550 jippermettilek li jkollhom l- bqija ta 'kwalunkwe għandek. 1892 01:25:59,550 --> 01:26:03,620 Mela jekk ikollna tassew, tassew numri kbar fil Caesar, 1893 01:26:03,620 --> 01:26:06,117 dak jekk aħna għandna l-aħħar ta 'sensiela ta' Vigenere? 1894 01:26:06,117 --> 01:26:08,450 Kif inti se tkun tista ' li tikseb li biex nagħlaq madwar? 1895 01:26:08,450 --> 01:26:11,330 Jekk I hit z u nixtieq li tmur lura għal, 1896 01:26:11,330 --> 01:26:13,650 kif am I se tikseb li biex nagħlaq madwar? 1897 01:26:13,650 --> 01:26:15,960 Probabilment tixtieq li tuża modulo fil hemm x'imkien. 1898 01:26:15,960 --> 01:26:19,190 >> It-tieni nett, jibbrawżjaw madwar librerija tiegħek. ctype.h. 1899 01:26:19,190 --> 01:26:20,680 Li l-librerija ġdida għandna. 1900 01:26:20,680 --> 01:26:25,270 Inti ser issib ħafna ta 'tassew, tassew isupper functions-- utli, islower, 1901 01:26:25,270 --> 01:26:27,681 toupper, tolower, isalpha, eċċetera. 1902 01:26:27,681 --> 01:26:30,680 Funzjonijiet kollha li se jkunu utli ħafna meta inti qed jippruvaw figura out, 1903 01:26:30,680 --> 01:26:33,780 huwa dan il-karattru ittra lowercase? 1904 01:26:33,780 --> 01:26:35,730 Kif nista jikkonvertu dan string għal uppercase? 1905 01:26:35,730 --> 01:26:38,146 Dawn l-affarijiet se jkunu ħafna, utli ħafna għall pset tiegħek. 1906 01:26:38,146 --> 01:26:42,720 1907 01:26:42,720 --> 01:26:45,500 KOLLOX SEW. 1908 01:26:45,500 --> 01:26:49,644 >> Ħinijiet tal-uffiċċju tonight huma 8:00 biex 11:00 fil-klassi TEAL għada 1909 01:26:49,644 --> 01:26:51,310 kif ukoll l-Erbgħa u l-Ħamis bil-lejl. 1910 01:26:51,310 --> 01:26:53,280 Ħinijiet tal-uffiċċju huma commons. 1911 01:26:53,280 --> 01:26:56,180 Ħafna jissuġġerixxu inti guys kollha tibda dritt bogħod, 1912 01:26:56,180 --> 01:27:00,490 għaliex inti ma tridx tkun dik kid li il-Ħamis bil-lejl għandu problemi 1913 01:27:00,490 --> 01:27:03,870 sottomissjoni pset tiegħek u huwa bħal, jien ma jafu x'għandhom jagħmlu. 1914 01:27:03,870 --> 01:27:05,870 I beda, I lest, I sottomessi. 1915 01:27:05,870 --> 01:27:09,737 Ipprova tagħti lilek innifsek xi kamra, għaliex dejjem jinqalgħu problemi kodiċi. 1916 01:27:09,737 --> 01:27:11,570 Inti tixtieq tagħmel ċert li inti tagħti lilek innifsek 1917 01:27:11,570 --> 01:27:14,810 ħafna ħin biex ikunu jistgħu biex jitlesta l-psets. 1918 01:27:14,810 --> 01:27:15,310 Kessaħ. 1919 01:27:15,310 --> 01:27:16,720 I ser hang madwar hawn. 1920 01:27:16,720 --> 01:27:18,226 >> UDJENZA: Huwa dan online diġà? 1921 01:27:18,226 --> 01:27:20,850 ANDI Peng: I do not know jekk huwa online diġà, iżda se jkun. 1922 01:27:20,850 --> 01:27:23,500 I ser hang madwar hawn jekk xi ħadd ikollu xi mistoqsijiet diġà. 1923 01:27:23,500 --> 01:27:25,390 Grazzi għall ġejjin. 1924 01:27:25,390 --> 01:27:27,105