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>> DAVID Malan: Kull dritt.

3
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Merħba lura għall CS50.

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Dan huwa l-bidu tal-ġimgħa d 8.

5
00:00:16,190 --> 00:00:21,320
U tfakkar li problema sett 5 intemm
bi ftit ta 'sfida.

6
00:00:21,320 --> 00:00:25,210
Allura jekk wieħed jassumi inti rkuprati kollha ta 'tiegħek
Fellows tagħlim u ritratti CA

7
00:00:25,210 --> 00:00:30,480
fil-fajl card.raw, inti eliġibbli
li issa jsibu kollha ta 'dawk in-nies, u

8
00:00:30,480 --> 00:00:34,510
rebbieħ wieħed xxurtjati se jimxu dar ma 'wieħed
ta 'dawn l-affarijiet, il-mozzjoni qabża

9
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mezz li tista 'tuża għall finali
proġetti, per eżempju.

10
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>> Dan, kull sena, iwassal għal
daqsxejn ta creepiness.

11
00:00:39,860 --> 00:00:43,480
U hekk dak li ħsibt I d tagħmel huwa sehem
miegħek xi wħud mill-noti li għandhom

12
00:00:43,480 --> 00:00:47,370
marret quddiem u lura fuq
il-lista tal-persunal ta tard.

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Per eżempju, biss aħħar lejl, kwotazzjoni
unquote, minn wieħed mill-istaff

14
00:00:51,110 --> 00:00:55,000
membri, "I biss kellhom riperkussjonijiet student
fuq bieb tiegħi li jieħdu ritratt miegħi.

15
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Stalkers, I jgħidlek. "Bdiet
pjuttost deskrittiva u mbagħad aħna mċaqalqa

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fuq, kull siegħa jew hekk aktar tard, "I kellhom
student stennija għalija wara taqsima

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u kellu kollha ta 'ismijiet tagħna u ritratti
fuq xi folji tal-karta. "Kull dritt.

18
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Hekk organizzat, iżda mhux
dak kollu li creepy għadu.

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>> Imbagħad, "I kien barra mill-belt din weekend,
u meta sirt lura, kien hemm waħda fil

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tiegħi

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kamra tas-sodda. "[Rires]

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DAVID Malan: kwotazzjoni Next minn staff
membru, "student waslet għall-dar tiegħi fil

23
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Somerville fil 04:00 dalgħodu. "Li jmiss
persunal, "I ltqajna biex lukanda tiegħi f'San

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Francisco u student kien stennija għal
me fil-lobby bi tliet DSLRs. "

25
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Tip ta 'kamera.

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"Jien ma anki fuq staff dan is-semestru,
iżda student kissru fis-dar tiegħi dan

27
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filgħodu u rreġistrati l-ħaġa sħiħa
ma 'Google ħġieġ. "U mbagħad fl-aħħar,

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"Mill-inqas 12-il persuna kienu eagerly
jistennew għalija meta I ltqajna barra tal tiegħi

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LIMO, u mbagħad I

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woke up. "Kull dritt.

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Allura fost l-ritratti, kif inti tista '
ifakkar, huma dan sħabi hawnhekk, li inti

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tista 'tkun taf kif Milo Banana, li jgħix
ma Lauren Carvalho, ras tagħna

33
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tagħlim Fellow.

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Milo, Milo, jiġu hawn boy.

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Milo.

36
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Milo.

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Mind you, hu liebes Google ħġieġ, hekk
aħna ser nuruk kollha ta 'dan wara.

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Allura dan huwa Milo jekk inti tixtieq li
jieħdu ritratt miegħu afterward.

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00:02:16,190 --> 00:02:18,240
Jekk inti tixtieq li toqgħod attent
fil-udjenza hemm.

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OK.

41
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C'est footage tajba.

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Ukoll, Milo Banana.

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Oh, ma tagħmel dan.

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>> [Daħk]

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>> OK.

46
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Allura kelma imbagħad fuq dak li jinsab quddiem,
għaliex kif aħna jibdew transizzjoni,

47
00:02:34,550 --> 00:02:38,410
din il-ġimgħa speċifikament, minn Ċ
kmand linja ambjentali għall PHP u

48
00:02:38,410 --> 00:02:42,720
JavaScript u SQL u HTML u CSS fl
ambjent fuq l-internet, aħna ser tkun

49
00:02:42,720 --> 00:02:44,490
jgħammru inti ma 'l-
aktar għarfien għal

50
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proġetti finali li huma potenzjali.

51
00:02:46,010 --> 00:02:49,240
Lejn dan il-għan, il-kors għandu
tradizzjoni li jsiru seminars li

52
00:02:49,240 --> 00:02:50,950
huma dwar suġġetti tanġenzjali
għall-kors.

53
00:02:50,950 --> 00:02:54,330
Ħafna x'jaqsmu mal-programmazzjoni u l-
iżvilupp app u oħrajn, iżda

54
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mhux neċessarjament esplorata billi
sillabu stess il-kors tal.

55
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>> Mela jekk inti jistgħu jkunu interessati fil waħda
jew aktar ta 'seminars din is-sena,

56
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jirreġistraw fil cs50.net/seminar.

57
00:03:02,530 --> 00:03:06,170
Hemm seminars anzjani
fil cs50.net/seminars.

58
00:03:06,170 --> 00:03:10,620
U fuq ir-roster s'issa din is-sena
huma Apps Web aqwa mal Ruby fuq

59
00:03:10,620 --> 00:03:13,580
Binarji, li hija alternattiva
lingwa li PHP.

60
00:03:13,580 --> 00:03:14,900
Lingwistika komputazzjonali.

61
00:03:14,900 --> 00:03:18,710
Introduzzjoni għall IOS, li hija l-
pjattaforma li użaw għall-iPhone u

62
00:03:18,710 --> 00:03:19,850
iżvilupp iPad.

63
00:03:19,850 --> 00:03:22,890
JavaScript għal apps Web, aħna ser ikopru
li, iżda dan is-seminar, inti ser tmur

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00:03:22,890 --> 00:03:24,070
aktar fid-dettall.

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00:03:24,070 --> 00:03:27,390
>> Qabża Mozzjoni, hekk aħna ser attwalment ikollhom xi
tal-ħbieb tagħna mill Leap Mozzjoni,

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il-kumpanija stess, jingħaqdu magħna.

67
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Għada, fil-fatt, li jipprovdu
hands-on seminar, jekk

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ta 'interess għalik.

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Meteor.js, teknika alternattiva għal
użu JavaScript mhux fil-browser,

70
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iżda fuq server.

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00:03:39,970 --> 00:03:42,110
Node.js, li huwa ferm
f'dak vina kif ukoll.

72
00:03:42,110 --> 00:03:43,650
Sleek Disinn Android.

73
00:03:43,650 --> 00:03:46,990
Android tkun alternattiva popolari ħafna
għall IOS u Windows Phone

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00:03:46,990 --> 00:03:48,790
u pjattaformi mobbli oħra.

75
00:03:48,790 --> 00:03:51,180
U Web Sigurtà Difiża Attiva.

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>> Allura fil-fatt, jekk inti tixtieq
li jidħlu għal din, let me

77
00:03:54,590 --> 00:03:55,840
jagħmlu nota ta 'dan.

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00:03:55,840 --> 00:03:57,790
Aħna kuntenti ħafna li jgħidu li
ħbieb tagħna fuq Leap

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Mozzjoni, li hija l-istartjar -

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dan il-mezz verament biss daħal
out ftit xhur ilu -

81
00:04:01,300 --> 00:04:05,960
tkun graciously mogħtija 30 dawn il-mezzi
għall-klassi għal kif ħafna studenti, jekk

82
00:04:05,960 --> 00:04:08,670
inti tixtieq li jissellef il-hardware
lejn tmiem semestru u jużawh għall-

83
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proġett finali attwali.

84
00:04:10,390 --> 00:04:11,890
Huma jappoġġaw numru ta 'lingwi.

85
00:04:11,890 --> 00:04:16,040
Ħadd minnhom C, ħadd minnhom PHP, sabiex
tirrealizza wieħed jew aktar minn dawn is-seminars

86
00:04:16,040 --> 00:04:16,899
jistgħu jkunu ta 'interess.

87
00:04:16,899 --> 00:04:19,730
U kollha se jkunu iffilmjati
F'każ li m'intix kapaċi

88
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biex jattendu personalment.

89
00:04:21,380 --> 00:04:25,000
L-iskeda jitħabbru permezz
email kif aħna ssolidifikat kmamar.

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00:04:25,000 --> 00:04:28,460
>> U fl-aħħar, jekk inti tmur
projects.cs.50.net, din hija website

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għandna tinżamm kull sena li nistiednu
folks mill-komunità, fakultà,

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dipartimenti, persunal, u kemm
fi barra ta 'CS50 li

93
00:04:36,420 --> 00:04:37,730
tipproponi ideat għall-proġetti.

94
00:04:37,730 --> 00:04:39,050
Affarijiet ta 'interess għall gruppi ta' studenti.

95
00:04:39,050 --> 00:04:40,600
Things ta 'interess għall-dipartimenti.

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00:04:40,600 --> 00:04:43,990
Allura mbagħad hemm jekk int qed jitħabtu
l-inċertezza dwar dak li

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00:04:43,990 --> 00:04:46,700
yourself tixtieq tindirizza.

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>> Allura aħħar darba aħna introduċiet forsi
struttura tad-data aktar kumplessi minn aħna'd

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00:04:51,760 --> 00:04:53,300
jidhru fil-ġimgħat li għaddew.

100
00:04:53,300 --> 00:04:56,550
Aħna'd kienu jużaw arrays pretty
heureusement bħala utli jekk

101
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struttura tad-data simplistiku.

102
00:04:58,160 --> 00:05:00,570
Imbagħad aħna introdotti dawn, li
naturalment huma listi marbuta.

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U dak kien wieħed mill-motivazzjonijiet għall-
introduzzjoni ta 'din l-istruttura tad-data?

104
00:05:05,470 --> 00:05:06,930
Yeah?

105
00:05:06,930 --> 00:05:07,250
X'hemm li?

106
00:05:07,250 --> 00:05:08,080
>> UDJENZA: Daqs Dynamic.

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>> DAVID Malan: Daqs Dynamic.

108
00:05:09,040 --> 00:05:11,890
Allura billi array, inti għandek
taf daqs tagħha bil-quddiem meta

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00:05:11,890 --> 00:05:12,740
inti tatiha.

110
00:05:12,740 --> 00:05:14,380
Fil-lista marbuta, inti ma
għandek tkun taf li.

111
00:05:14,380 --> 00:05:17,610
Inti tista 'sempliċement malloc, jew b'mod iktar ġenerali,
jalloka addizzjonali

112
00:05:17,610 --> 00:05:20,720
node, biex ngħidu hekk, kwalunkwe ħin li inti
tixtieq li daħħal data aktar.

113
00:05:20,720 --> 00:05:22,670
U node tkun tifsira ebda predeterminat.

114
00:05:22,670 --> 00:05:25,580
Huwa biss terminu ġeneriku li jiddeskrivi
xi tip ta 'kontenitur li aħna qed

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00:05:25,580 --> 00:05:29,610
użu fl-istruttura tad-data tagħna biex jaħżnu
xi oġġett ta 'interess, li f'dan il-

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00:05:29,610 --> 00:05:31,750
każ jiġri li jkun interi.

117
00:05:31,750 --> 00:05:33,160
>> Iżda hemm dejjem tradeoff.

118
00:05:33,160 --> 00:05:38,070
Allura irridu jiksbu daqsijiet dinamiċi tad-data
istruttura, iżda b'liema prezz inħallsu?

119
00:05:38,070 --> 00:05:40,040
X'hemm l-tnaqqis ta 'listi marbuta?

120
00:05:40,040 --> 00:05:41,006
Yeah?

121
00:05:41,006 --> 00:05:41,980
>> UDJENZA: Jirrikjedi memorja aktar.

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>> DAVID Malan: Hija teħtieġ aktar
memorja, kif eżattament?

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00:05:44,240 --> 00:05:46,440
>> UDJENZA: [inaudible].

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00:05:46,440 --> 00:05:47,050
>> DAVID Malan: Eżattament.

125
00:05:47,050 --> 00:05:50,460
Allura issa għandna pointers bidu
memorja addizzjonali li aħna qabel

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ma kellhomx bżonn, minħabba li l-vantaġġ
ta 'firxa, naturalment, huwa li

127
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kollox huwa kontigwa, lura
lura biex lura, li

128
00:05:54,860 --> 00:05:56,380
jagħtik aċċess bl-addoċċ.

129
00:05:56,380 --> 00:06:00,710
Minħabba biss bl-użu bracket kwadru
notazzjoni, jew teknikament aktar pointer

130
00:06:00,710 --> 00:06:03,580
aritmetika, minbarra sempliċi ħafna,
inti tista 'aċċess kwalunkwe

131
00:06:03,580 --> 00:06:05,700
elementi fil-ħin kostanti.

132
00:06:05,700 --> 00:06:08,975
U fil-fatt, li tip ta 'ssemmi
prezz ieħor li aħna qed tħallas bil-

133
00:06:08,975 --> 00:06:09,760
lista marbuta.

134
00:06:09,760 --> 00:06:13,890
>> X'jiġri mill-running time ta '
xi ħaġa simili Search, jekk irrid

135
00:06:13,890 --> 00:06:17,270
ssib xi valur u ġewwa
ta 'lista marbut?

136
00:06:17,270 --> 00:06:20,290
X'jagħmel running time tiegħi sar?

137
00:06:20,290 --> 00:06:21,560
Big O ta 'n.

138
00:06:21,560 --> 00:06:24,060
Jekk huwa magħżula għal?

139
00:06:24,060 --> 00:06:25,440
X'jiġri jekk s magħżula l-istruttura tad-data?

140
00:06:25,440 --> 00:06:28,640
Nista 'nagħmel aħjar minn big
O ta 'n għat-tiftix?

141
00:06:28,640 --> 00:06:31,700
Le, għaliex fl-agħar każ tista '
tajjeb ħafna jiġu magħżula, iżda n-numru

142
00:06:31,700 --> 00:06:32,950
qed tfittex jista 'jkun kbir.

143
00:06:32,950 --> 00:06:35,370
Jista 'jkun in-numru 100, li
jista 'jiġri li tkun kollha

144
00:06:35,370 --> 00:06:36,410
il-mod fl-aħħar.

145
00:06:36,410 --> 00:06:39,950
U għaliex inti tista 'biss aċċess linked
lista f'dan l-implimentazzjoni mill-

146
00:06:39,950 --> 00:06:42,690
mod ta 'l-ewwel node tagħha, int
xorta tip ta 'minn xortih.

147
00:06:42,690 --> 00:06:47,450
Int għandek travers il-ħaġa sħiħa
mill-ewwel għall-aħħar sabiex isibu

148
00:06:47,450 --> 00:06:49,150
li l-valur kbar bħall 100.

149
00:06:49,150 --> 00:06:51,350
Jew biex jiddeterminaw jekk huwa
lanqas hemm.

150
00:06:51,350 --> 00:06:55,960
>> Allura ma nistgħux nagħmlu dak algoritmu fi data
struttura li tidher bħal dan?

151
00:06:55,960 --> 00:06:59,460
Aħna ma tistax tagħmel tfittxija binarju, minħabba
tfittxija binarju meħtieġ li kellna

152
00:06:59,460 --> 00:07:00,740
aċċess bl-addoċċ.

153
00:07:00,740 --> 00:07:04,500
Nistgħu biss qabża minn post għal
post mingħajr ma jkollhom isegwu

154
00:07:04,500 --> 00:07:07,080
dawn frak tal-ħobż fil-forma
ta 'dawn pointers.

155
00:07:07,080 --> 00:07:08,300
>> Issa, kif ma nimplimentaw dan?

156
00:07:08,300 --> 00:07:12,830
Ukoll, jekk immorru l-iskrin hawn, jekk
nistgħu malajr reimplement din id-data

157
00:07:12,830 --> 00:07:13,440
istruttura -

158
00:07:13,440 --> 00:07:15,670
kalligrafija tiegħi li mhux kollha li
kbira hawn, iżda aħna ser nippruvaw.

159
00:07:15,670 --> 00:07:22,030
Struct Allura typedef, u dak li għamlet I
tixtieq li sejħa dan ħaġa up here?

160
00:07:22,030 --> 00:07:22,960
Node.

161
00:07:22,960 --> 00:07:24,580
So I ser tingħata us beda.

162
00:07:24,580 --> 00:07:27,860
U issa, dak li jeħtieġ li jkun ġewwa ta '
l-istruttura tad-data għal dak weħidhom

163
00:07:27,860 --> 00:07:28,430
marbuta lista?

164
00:07:28,430 --> 00:07:29,950
Kif oqsma ħafna?

165
00:07:29,950 --> 00:07:30,450
>> Allura tnejn.

166
00:07:30,450 --> 00:07:31,570
Wieħed huwa pjuttost faċli.

167
00:07:31,570 --> 00:07:33,050
Allura int n.

168
00:07:33,050 --> 00:07:35,930
U aħna tista 'sejħa n xejn irridu,
iżda għandu jkun int jekk aħna qed

169
00:07:35,930 --> 00:07:37,660
implimentazzjoni ta 'lista marbuta għall ints.

170
00:07:37,660 --> 00:07:41,920
U issa dak ma-tieni
qasam għandhom ikunu?

171
00:07:41,920 --> 00:07:43,460
Struct node *.

172
00:07:43,460 --> 00:07:50,570
Mela jekk nagħmel Struct node *, u mbagħad I
tista 'sejħa dan ukoll kwalunkwe I jixtiequ,

173
00:07:50,570 --> 00:07:53,510
iżda biss li tkun ċara I ser sejħa
dan li jmiss, kif aħna kont qed tagħmel.

174
00:07:53,510 --> 00:07:55,270
U allura jien ser tagħlaq braces kaboċċi tiegħi.

175
00:07:55,270 --> 00:08:00,700
>> U issa, kif l-aħħar darba,
Nressaq node stabbiliti hawn.

176
00:08:00,700 --> 00:08:03,830
Imma jekk jien tiddikjara dan huwa bħala
node, għaliex ma I jolqot li huma tant

177
00:08:03,830 --> 00:08:07,320
verbose hawn fil tiddikjara Struct
node * li jmiss, għall-kuntrarju

178
00:08:07,320 --> 00:08:09,210
għal ftit node * jmiss?

179
00:08:09,210 --> 00:08:09,904
Yeah?

180
00:08:09,904 --> 00:08:12,810
>> UDJENZA: [inaudible].

181
00:08:12,810 --> 00:08:14,050
>> DAVID Malan: Eżattament.

182
00:08:14,050 --> 00:08:14,530
Eżattament.

183
00:08:14,530 --> 00:08:18,320
Minħabba C verament tieħdok litteralment u
biss jara d-definizzjoni ta node

184
00:08:18,320 --> 00:08:21,230
mod stabbiliti hawn, inti ma tistax
jirreferu għaliha up here.

185
00:08:21,230 --> 00:08:24,760
Allura aħna għandna dan it-tip ta 'preemptive
dikjarazzjoni hawnhekk, li hija ċertament

186
00:08:24,760 --> 00:08:25,390
aktar verbose.

187
00:08:25,390 --> 00:08:27,810
Struct node, dan ifisser
aħna issa tista 'aċċess

188
00:08:27,810 --> 00:08:29,760
ġewwa tal-istruttura tad-data.

189
00:08:29,760 --> 00:08:33,370
>> U bħala twarrib, għaliex dan huwa
isir ftit aktar suġġettiva issa,

190
00:08:33,370 --> 00:08:36,230
l-istilla jistgħu teknikament mur hawn,
ikun jista 'jimxi hawn, tista'

191
00:08:36,230 --> 00:08:37,179
anki jmorru fin-nofs.

192
00:08:37,179 --> 00:08:39,890
Imxejna adottat, fil-Gwida tal-Istil għall
il-kors, il-konvenzjoni ta 'tqegħid

193
00:08:39,890 --> 00:08:42,299
l-istilla dritt li jmiss għall-informazzjoni
tip, li f'dan il-każ,

194
00:08:42,299 --> 00:08:43,460
ikun node Struct.

195
00:08:43,460 --> 00:08:46,620
Iżda realizzata fil-lott ta 'kotba u
referenzi online, inti tista 'tabilħaqq

196
00:08:46,620 --> 00:08:48,450
tara fuq in-naħa l-oħra.

197
00:08:48,450 --> 00:08:52,200
Iżda biss jirrealizzaw li kemm fil-fatt se
jaħdmu u inti għandek sempliċement tkun

198
00:08:52,200 --> 00:08:52,970
konsistenti.

199
00:08:52,970 --> 00:08:53,580
>> Kull dritt.

200
00:08:53,580 --> 00:08:55,630
Allura li kien dikjarazzjoni tagħna
ta node Struct.

201
00:08:55,630 --> 00:08:59,430
Imma allura aħna bdiet tagħmel aktar
affarijiet sofistikati.

202
00:08:59,430 --> 00:09:03,410
Per eżempju, aħna iddeċieda li jintroduċi
xi ħaġa bħal tabella hash.

203
00:09:03,410 --> 00:09:08,160
Allura hawnhekk huwa tabella hash tal n daqs,
indiċjati minn 0 fuq il-quċċata xellug għal n

204
00:09:08,160 --> 00:09:09,690
minus 1 fuq il-qiegħ tax-xellug.

205
00:09:09,690 --> 00:09:11,640
Dan jista 'jkun hash
tabella għal xejn.

206
00:09:11,640 --> 00:09:15,340
Imma liema tipi ta 'affarijiet ma nitkellmu
dwar l-użu ta 'tabella hash għall?

207
00:09:15,340 --> 00:09:18,370
Kif taħżen liema?

208
00:09:18,370 --> 00:09:18,800
>> Ismijiet.

209
00:09:18,800 --> 00:09:20,870
Stajna nagħmlu ismijiet simili
għamilna aħħar darba.

210
00:09:20,870 --> 00:09:22,200
U tassew, inti jista 'jaħżen xejn.

211
00:09:22,200 --> 00:09:24,640
U aħna ser tara dan mill-ġdid fl
PHP u JavaScript.

212
00:09:24,640 --> 00:09:28,550
A tabella hash huwa tip sbieħ ta 'Swiss
Sikkina Armata li tippermetti int taħżen

213
00:09:28,550 --> 00:09:33,690
pretty ħafna xi trid ġewwa tal
dan billi jassoċjaw ċwievet b'valuri.

214
00:09:33,690 --> 00:09:34,770
Keys b'valuri.

215
00:09:34,770 --> 00:09:37,800
>> Issa f'dan il-każ sempliċi, tagħna
ċwievet huma biss numri.

216
00:09:37,800 --> 00:09:40,380
Aħna qed timplimenta hash
tabella bħala firxa.

217
00:09:40,380 --> 00:09:43,500
U għalhekk il-keys huma 0,
1, 2, u oħrajn.

218
00:09:43,500 --> 00:09:47,200
U hekk aħna, bħala bnedmin, iddeċieda aħħar
ġimgħa li inti taf liema, jekk aħna qed

219
00:09:47,200 --> 00:09:50,410
ser ismijiet taħżen, ejja biss
arbitrarju, iżda pjuttost raġonevolment,

220
00:09:50,410 --> 00:09:54,680
jassumu li Alice, isem A,
biss se jiġu indiċjati fis 0.

221
00:09:54,680 --> 00:09:58,030
U Bob, isem B, se jiġu indiċjati
fis 1, u oħrajn.

222
00:09:58,030 --> 00:10:02,490
Allura kellna mapping bejn inputs,
li huma kordi, u l-hash

223
00:10:02,490 --> 00:10:04,560
postijiet, li huma numri.

224
00:10:04,560 --> 00:10:07,740
>> Allura dak il-proċess hija ġeneralment magħrufa bħala
funzjoni hash, u inti tista 'verament

225
00:10:07,740 --> 00:10:09,130
timplimentah fil-kodiċi.

226
00:10:09,130 --> 00:10:12,080
Jekk jien ridt li jimplimenta funzjoni hash
li ma eżattament dak li aħna

227
00:10:12,080 --> 00:10:17,070
biss deskritta minn aħħar darba, I jista
tiddikjara funzjoni li jieħu, bħala

228
00:10:17,070 --> 00:10:18,330
input per eżempju -

229
00:10:18,330 --> 00:10:22,190
u ejja tagħmel dan fuq dan
iskrin hawn fuq.

230
00:10:22,190 --> 00:10:26,180
Jekk jien ridt li timplimenta hash
funzjoni, I jista 'jgħid

231
00:10:26,180 --> 00:10:27,410
xi ħaġa bħal din.

232
00:10:27,410 --> 00:10:29,030
>> Huwa ser jirritorna int.

233
00:10:29,030 --> 00:10:33,600
Huwa ser jiġi msejjaħ hash, u huwa
ser jaċċetta bħala argument a

234
00:10:33,600 --> 00:10:38,920
spag, jew nistgħu nkunu aktar xierqa issa,
u jgħidu char *, aħna ser sejħa hija s.

235
00:10:38,920 --> 00:10:43,840
U allura dan kollu funzjoni għandha tagħmel,
finalment, huwa jirritorna l-int.

236
00:10:43,840 --> 00:10:45,990
Issa, kif tagħmlu li jista
ma jkunx tant ċara.

237
00:10:45,990 --> 00:10:49,510
Jien ser timplimenta din mingħajr ebda
forma ta 'żball verifika dritt issa.

238
00:10:49,510 --> 00:10:55,740
Jien biss ser addoċċ ngħid, ritorn
dak kollu li huwa fil-parentesi s 0, minus,

239
00:10:55,740 --> 00:10:58,850
ejja ngħidu, il-kapital A virgola.

240
00:10:58,850 --> 00:10:59,960
>> Totalment imkisser.

241
00:10:59,960 --> 00:11:02,620
Huwa mhux perfett għax
wieħed, dak li jekk i huwa null?

242
00:11:02,620 --> 00:11:04,000
Affarijiet ħżiena huma jiġri.

243
00:11:04,000 --> 00:11:07,940
Żewġ, dak li jekk l-ewwel ittra f'dan
isem mhuwiex ittra kapitali?

244
00:11:07,940 --> 00:11:09,860
Li mhux se jduru
out ukoll lanqas.

245
00:11:09,860 --> 00:11:11,970
Jista 'jkun ittra lowercase
jew mhux ittra fil-livelli kollha.

246
00:11:11,970 --> 00:11:15,520
Allura totalment isir sforz akbar,
iżda din hija l-idea bażika.

247
00:11:15,520 --> 00:11:19,010
>> Dak li aħna deskritti aħħar ġimgħa verbalment kif
biss proċess ta 'immappjar Alice biex

248
00:11:19,010 --> 00:11:23,360
0 u Bob sa 1 jista 'jiġi espress
ċertament aktar formulaically bħala C

249
00:11:23,360 --> 00:11:24,320
jiffunzjonaw hawn.

250
00:11:24,320 --> 00:11:28,630
Imsejħa mill-ġdid hash, tieħu string bħala
input, u mbagħad b'xi mod ma xi ħaġa

251
00:11:28,630 --> 00:11:31,020
ma 'dak input li jipproduċi output.

252
00:11:31,020 --> 00:11:34,130
Mhux b'differenza deskrizzjoni tagħna kaxxa sewda
li konna twil isir.

253
00:11:34,130 --> 00:11:36,550
I do not know kif dan jista 'jkun
taħdem taħt il-barnuża.

254
00:11:36,550 --> 00:11:40,120
>> Għal problema sett 6, waħda mill-isfidi
hija għalik li jiddeċiedu liema

255
00:11:40,120 --> 00:11:41,920
se funzjoni hash tiegħek tkun?

256
00:11:41,920 --> 00:11:45,760
Dak li għaddej biex tkun ġewwa ta 'dik iswed
kaxxa, u preżumibbilment, li ser tkun

257
00:11:45,760 --> 00:11:50,380
ftit aktar interessanti minn dan, u
definittivament aktar suxxettibbli għall-iżbalji

258
00:11:50,380 --> 00:11:53,180
verifika minn din partikolari
implimentazzjoni.

259
00:11:53,180 --> 00:11:54,580
>> Imma l-problemi jistgħu jinqalgħu, right?

260
00:11:54,580 --> 00:11:57,760
Jekk għandna struttura data bħal din
waħda, x'hemm waħda mill-problemi

261
00:11:57,760 --> 00:12:01,600
inti tista 'taħdem fis maż-żmien kif inti daħħal
aktar u aktar ismijiet fil-

262
00:12:01,600 --> 00:12:02,880
tabella hash?

263
00:12:02,880 --> 00:12:04,630
Ikollok kolliżjonijiet, id-dritt?

264
00:12:04,630 --> 00:12:07,560
X'jiġri jekk ikollok Alice u Aaron,
żewġ persuni li isimhom ġara

265
00:12:07,560 --> 00:12:08,190
biex tibda bil A?

266
00:12:08,190 --> 00:12:11,660
Li iqajjem il-kwistjoni, fejn inti
tpoġġi t-tieni bħall-isem?

267
00:12:11,660 --> 00:12:15,050
>> Ukoll, inti tista 'naively biss jitqiegħed
fejn Bob jappartjeni, iżda mbagħad Bob huwa

268
00:12:15,050 --> 00:12:17,300
tip ta 'invitat jekk inti tipprova
daħħal l-isem tiegħu li jmiss u

269
00:12:17,300 --> 00:12:18,240
hemm l-ebda lok għalih.

270
00:12:18,240 --> 00:12:21,400
Allura inti tista 'tpoġġi Bob fejn Charlie huwa,
u tista 'timmaġina dan malajr ħafna

271
00:12:21,400 --> 00:12:23,020
jiddevolvu fis daqsxejn ta 'mess.

272
00:12:23,020 --> 00:12:25,600
Xi ħaġa lineari fl-aħħar, fejn inti
biss għandek tfittex l-ħaġa sħiħa

273
00:12:25,600 --> 00:12:28,190
tfittex Alice jew Bob
jew Aaron jew Charlie.

274
00:12:28,190 --> 00:12:33,230
>> Allura minflok aħna propost, minflok sempliċiment
linearment probing għal spazji miftuħa

275
00:12:33,230 --> 00:12:36,450
u plopping-ismijiet hemmhekk, aħna
pproponiet approċċ fancier.

276
00:12:36,450 --> 00:12:41,740
A tabella hash implimentati xorta ma '
firxa ta 'indiċi, iżda t-tip ta' data

277
00:12:41,740 --> 00:12:44,500
dawk indiċijiet issa kienu pointers.

278
00:12:44,500 --> 00:12:47,360
Pointers għal dak?

279
00:12:47,360 --> 00:12:48,730
Pointers għal listi marbuta.

280
00:12:48,730 --> 00:12:53,330
>> Minħabba recall li lista marbut huwa
verament ftit pointer għal node, u

281
00:12:53,330 --> 00:12:57,110
l-node għandha qasam li jmiss, u li node
għandha kamp li jmiss, u oħrajn.

282
00:12:57,110 --> 00:13:00,690
Allura inti issa tista 'taħseb dan array fuq
in-naħa tax-xellug ta 'tabella hash bħala

283
00:13:00,690 --> 00:13:01,820
jwassal għal lista marbuta.

284
00:13:01,820 --> 00:13:07,000
Il-vantaġġ ta 'liema hija jekk ikollok
ħabta bejn Alice u Aaron,

285
00:13:07,000 --> 00:13:09,300
x'tagħmel mal-
tieni persuna?

286
00:13:09,300 --> 00:13:14,150
Inti biss ehmeż lilu jew tagħha għall-
aħħar, jew saħansitra l-bidu

287
00:13:14,150 --> 00:13:15,490
ta 'dik il-lista marbuta.

288
00:13:15,490 --> 00:13:17,340
>> U fil-fatt, ejja biss noodle permezz
li għal ftit tieni.

289
00:13:17,340 --> 00:13:18,640
Fejn jagħmel l-iktar sens?

290
00:13:18,640 --> 00:13:22,060
Jekk I daħħal Alice u hi jispiċċa fil
l-ewwel post, imbagħad I jippruvaw

291
00:13:22,060 --> 00:13:25,310
daħħal l-isem Aaron, u hemm
ovvjament ħabta, għandu nressaq

292
00:13:25,310 --> 00:13:27,400
lilu fil-bidu
tal-lista marbuta?

293
00:13:27,400 --> 00:13:30,944
C'est f'dak ewwel post,
jew fl-aħħar?

294
00:13:30,944 --> 00:13:31,440
>> UDJENZA: [inaudible].

295
00:13:31,440 --> 00:13:31,990
>> DAVID Malan: OK.

296
00:13:31,990 --> 00:13:32,490
Smajt bidu.

297
00:13:32,490 --> 00:13:33,903
Għaliex fil-bidu?

298
00:13:33,903 --> 00:13:34,750
>> UDJENZA: [inaudible].

299
00:13:34,750 --> 00:13:34,940
>> DAVID Malan: OK.

300
00:13:34,940 --> 00:13:36,520
Huwa alfabetika, hekk li sbieħ.

301
00:13:36,520 --> 00:13:37,330
Li l-proprjetà tajba.

302
00:13:37,330 --> 00:13:39,335
Hija se jiffrankaw me xi żmien potenzjalment.

303
00:13:39,335 --> 00:13:43,290
Dan mhux se let me do tfittxija binarja, iżda I
jista inqas ikunu jistgħu break out

304
00:13:43,290 --> 00:13:47,340
ta 'linja jekk I realizzata, ukoll, jien mod
passat kienu Aaron ma jkunx f'din

305
00:13:47,340 --> 00:13:48,310
magħżula lista linked.

306
00:13:48,310 --> 00:13:50,360
I ma jkollhom l-iskart ħin tiegħi tfittex
it-triq kollha sa l-aħħar.

307
00:13:50,360 --> 00:13:51,530
Allura dak raġonevoli.

308
00:13:51,530 --> 00:13:54,710
Għaliex inkella jista inti tixtieq li daħħal
l-isem jaħbtu fl-

309
00:13:54,710 --> 00:13:56,660
bidu tal-lista?

310
00:13:56,660 --> 00:13:57,397
X'hemm li?

311
00:13:57,397 --> 00:13:58,680
>> UDJENZA: [inaudible].

312
00:13:58,680 --> 00:14:00,820
>> DAVID Malan: Hija tista 'tieħu żmien twil
biex jiksbu l-aħħar tal-lista.

313
00:14:00,820 --> 00:14:02,490
U fil-fatt, aktar u aktar.

314
00:14:02,490 --> 00:14:04,920
L-ismijiet aktar inti daħħal li
tibda bil A, l-itwal li

315
00:14:04,920 --> 00:14:06,280
katina hija se tikseb.

316
00:14:06,280 --> 00:14:07,890
L-itwal li marbuta
lista hija se tikseb.

317
00:14:07,890 --> 00:14:09,420
Allura int verament ftit
ħela ta 'ħin tiegħek.

318
00:14:09,420 --> 00:14:14,070
Forsi int aħjar off żamma
ħin tad-dħul kostanti, big O ta '1,

319
00:14:14,070 --> 00:14:18,470
billi dejjem tqegħid-isem jaħbtu fi
il-bidu tal-lista marbuta,

320
00:14:18,470 --> 00:14:21,230
u mhux inkwetanti kemm
dwar issortjar.

321
00:14:21,230 --> 00:14:22,600
>> X'inhu l-aħjar risposta?

322
00:14:22,600 --> 00:14:23,320
Huwa ċar.

323
00:14:23,320 --> 00:14:26,140
Huwa tip ta 'tiddependi fuq dak li l-
distribuzzjoni huwa, dak li l-mudell huwa

324
00:14:26,140 --> 00:14:27,850
mill-ismijiet inti ddaħħal.

325
00:14:27,850 --> 00:14:29,430
Mhuwiex neċessarjament
risposta ovvja.

326
00:14:29,430 --> 00:14:33,100
Iżda hawn biex, għal darb'oħra, huwa
opportunità disinn.

327
00:14:33,100 --> 00:14:37,220
>> Allura aħna mbagħad ħares lejn din il-ħaġa, li
huwa verament l-opportunità kbira oħra

328
00:14:37,220 --> 00:14:38,180
għal p-set 6.

329
00:14:38,180 --> 00:14:41,770
U jirrealizzaw, jekk inti ma jkunux diġà,
Ads Zamyla fis kemm ta 'dawn, hash

330
00:14:41,770 --> 00:14:43,260
tabelli u tipprova, f'aktar dettall.

331
00:14:43,260 --> 00:14:45,630
U l-walkthrough video huwa
inkorporati fil-p-set spec.

332
00:14:45,630 --> 00:14:46,590
Dan kien trie -

333
00:14:46,590 --> 00:14:51,670
T-R-I-E. U dak li kien interessanti dwar
dan kienet li l-running time

334
00:14:51,670 --> 00:14:59,510
ta 'tiftix għal isem, bħal Maxwell
aħħar darba, kien big O ta 'dak?

335
00:14:59,510 --> 00:15:01,040
X'hemm li?

336
00:15:01,040 --> 00:15:01,920
>> UDJENZA: In-numru ta 'ittri.

337
00:15:01,920 --> 00:15:02,550
>> DAVID Malan: Numru ta 'ittri.

338
00:15:02,550 --> 00:15:03,210
Smajt żewġ affarijiet.

339
00:15:03,210 --> 00:15:04,630
Numru ta 'ittri u l-ħin kostanti.

340
00:15:04,630 --> 00:15:05,540
Mela ejja jmorru ma 'dak l-ewwel.

341
00:15:05,540 --> 00:15:06,410
In-numru ta 'ittri.

342
00:15:06,410 --> 00:15:10,195
Ukoll, din l-istruttura tad-data, recall, huwa
bħal siġra, siġra tal-familja, li kull wieħed

343
00:15:10,195 --> 00:15:12,860
lymph li huma magħmula minn arrays.

344
00:15:12,860 --> 00:15:16,300
U dawk arrays huma pointers għal
lymph oħra bħal dawn, jew oħra bħal

345
00:15:16,300 --> 00:15:17,670
arrays fil-siġra.

346
00:15:17,670 --> 00:15:22,890
>> Hekk jekk ridna li mbagħad tiddetermina
jekk Maxwell hija fil hawn, I jista 'jmur

347
00:15:22,890 --> 00:15:26,890
għall-ewwel firxa, fuq nett tal-
l-siġra, l-għerq hekk imsejħa, quċċata ta '

348
00:15:26,890 --> 00:15:30,521
il-trie, u mbagħad segwi l-pointer m,
allura l-pointer a, allura x,

349
00:15:30,521 --> 00:15:31,710
w, e, l, l.

350
00:15:31,710 --> 00:15:34,910
U mbagħad meta nara xi simbolu speċjali,
denotat hawn bħala trijangolu.

351
00:15:34,910 --> 00:15:38,480
Fil kodiċi tkun taf tara nipproponu li inti
implimentati bħala bool, biss qal iva

352
00:15:38,480 --> 00:15:40,540
jew xejn, ta 'kelma jieqaf hawn.

353
00:15:40,540 --> 00:15:45,270
>> Ukoll, ladarba aħna ħadthom marret M-A-X-W-E-L-L,
jħoss simili seba, forsi

354
00:15:45,270 --> 00:15:48,910
tmienja jekk immorru waħda passat, tmien
passi biex isibu Maxwell.

355
00:15:48,910 --> 00:15:53,050
Jew ejja sejħa hija K. Imma recall aħħar
time, I argumentat li jekk hemm

356
00:15:53,050 --> 00:15:57,540
realistikament tul massimu fuq
kelma, bħal karattri 40-xi-fard, a

357
00:15:57,540 --> 00:16:00,810
tul massimu jimplika
valur kostanti.

358
00:16:00,810 --> 00:16:05,770
Allura verament, iva, huwa teknikament O big
tat-8 jew 7, jew O verament kbir ta 'K. Imma

359
00:16:05,770 --> 00:16:09,420
jekk ikun hemm limitu finite dwar liema
K jista 'jkun, huwa kostanti.

360
00:16:09,420 --> 00:16:12,080
U dan huwa big O ta '1 fil-
l-aħħar tal-ġurnata.

361
00:16:12,080 --> 00:16:13,040
>> Mhux fid-dinja reali.

362
00:16:13,040 --> 00:16:15,960
Mhux meta inti attwalment tibda jaraw
arloġġ tiegħek bħala running program tiegħek.

363
00:16:15,960 --> 00:16:20,690
Huwa assolutament se tkun daqsxejn
aktar kajman milli verament kostanti

364
00:16:20,690 --> 00:16:21,840
ħin ma 'pass wieħed.

365
00:16:21,840 --> 00:16:25,540
Huwa ser jkun ta 'seba' jew tmien passi,
iżda xorta dan huwa ħafna, ħafna aħjar

366
00:16:25,540 --> 00:16:30,080
minn algoritmu bħal big O ta 'n li
jiddependi mid-daqs ta 'x'hemm fil-

367
00:16:30,080 --> 00:16:31,220
struttura tad-data.

368
00:16:31,220 --> 00:16:34,970
>> Avviż tal-rasu hawnhekk hija li nistgħu daħħal
miljun ismijiet aktar fis dan

369
00:16:34,970 --> 00:16:38,170
struttura tad-data, imma kif ħafna aktar passi
huwa se jieħu magħna biex isibu

370
00:16:38,170 --> 00:16:40,480
Maxwell f'dak il-każ?

371
00:16:40,480 --> 00:16:40,780
Xejn.

372
00:16:40,780 --> 00:16:41,820
Hu affettwat.

373
00:16:41,820 --> 00:16:45,480
U sal-lum, ma naħsibx Rajna
eżempju ta 'struttura data jew

374
00:16:45,480 --> 00:16:48,560
algoritmu li kienet kompletament
affettwat mill esterna

375
00:16:48,560 --> 00:16:50,040
imgieba bħal dik.

376
00:16:50,040 --> 00:16:51,160
Iżda dan ma jistax ikun aqwa.

377
00:16:51,160 --> 00:16:52,900
Dan ma jistax ikun l-unika soluzzjoni
għall-p-set

378
00:16:52,900 --> 00:16:53,570
>> U mhuwiex.

379
00:16:53,570 --> 00:16:55,980
Dan mhuwiex neċessarjament id-data
istruttura għandek ixaqilbu,

380
00:16:55,980 --> 00:16:58,220
għaliex bħal tabelli hash, tradeoff.

381
00:16:58,220 --> 00:17:00,500
X'hemm-prezz li inti tħallas hawn?

382
00:17:00,500 --> 00:17:00,940
Memorja.

383
00:17:00,940 --> 00:17:02,890
I mean, dan huwa atroċi
ammont tal-memorja.

384
00:17:02,890 --> 00:17:05,569
U inti ma tistax pjuttost tara hawnhekk għaliex
l-awtur ta 'din l-istampa

385
00:17:05,569 --> 00:17:09,420
ovvjament maqtugħ kollha tal-arrays,
u aħna mhux qed jaraw lottijiet ta 'A u

386
00:17:09,420 --> 00:17:12,700
Tal-B u C tal-u l-Q u l-Y
u Z f'dawn l-arrays.

387
00:17:12,700 --> 00:17:13,630
Iżda dawn qed hemmhekk.

388
00:17:13,630 --> 00:17:17,660
>> Kull wieħed minn dawn lymph huwa firxa sħiħa
ta 'xi 26 jew aktar bytes, b'kull wieħed minn

389
00:17:17,660 --> 00:17:19,170
li jirrappreżenta ittra.

390
00:17:19,170 --> 00:17:22,920
27 fil-każ tagħna, sabiex inkunu nistgħu appoġġ
apostrophes fil-problema sett.

391
00:17:22,920 --> 00:17:27,030
Allura din l-istruttura tad-data huwa verament,
verament dens u wiesa '.

392
00:17:27,030 --> 00:17:30,880
U li waħdu jista 'jispiċċa jonqos
affarijiet isfel, jew għall-inqas jiswew inti

393
00:17:30,880 --> 00:17:32,240
spazju ħafna aktar.

394
00:17:32,240 --> 00:17:34,020
Iżda għal darb'oħra, nistgħu tiġbed
paraguni hawn.

395
00:17:34,020 --> 00:17:39,190
>> Recall ftit lura, ksibna ħafna
żmien aktar eċċitanti running fl-għażla

396
00:17:39,190 --> 00:17:42,880
meta nużaw tip jingħaqdu, imma l-prezz
aħna mħallsa biex tinkiseb n log n għall jingħaqdu

397
00:17:42,880 --> 00:17:46,930
sort meħtieġ li aħna jonfqu
aktar dak riżorsa?

398
00:17:46,930 --> 00:17:47,690
Aktar spazju.

399
00:17:47,690 --> 00:17:50,530
Għandna bżonn firxa sekondarja li
kopja nies fi, bħad

400
00:17:50,530 --> 00:17:51,620
għamilna hawn fuq il-palk.

401
00:17:51,620 --> 00:17:55,880
Għalhekk għal darb'oħra, l-ebda rebbieħa ċari,
iżda biss disinn suġġettiva

402
00:17:55,880 --> 00:17:57,710
deċiżjonijiet li jridu jittieħdu.

403
00:17:57,710 --> 00:17:58,060
>> Kull dritt.

404
00:17:58,060 --> 00:17:59,130
Allura kif dwar dan?

405
00:17:59,130 --> 00:18:02,050
Kulħadd jirrikonoxxu li D-Hall?

406
00:18:02,050 --> 00:18:02,440
OK.

407
00:18:02,440 --> 00:18:03,170
Allura tlieta minna.

408
00:18:03,170 --> 00:18:03,750
Mather House.

409
00:18:03,750 --> 00:18:05,070
Allura dan huwa għall dining Mather tal.

410
00:18:05,070 --> 00:18:09,650
I ser bet l-swali dining jkollhom
munzelli ta 'dixxijiet bħal dan.

411
00:18:09,650 --> 00:18:11,950
U dan huwa attwalment rappreżentattiv
ta 'xi ħaġa konna

412
00:18:11,950 --> 00:18:13,050
ovvjament jidher diġà.

413
00:18:13,050 --> 00:18:14,850
Aħna hija imsejħa litteralment munzell.

414
00:18:14,850 --> 00:18:18,970
U l-munzell, f'termini ta 'tiegħek
memorja tal-kompjuter, huwa fejn tmur data

415
00:18:18,970 --> 00:18:20,460
filwaqt funzjonijiet qed ikunu msejjħa.

416
00:18:20,460 --> 00:18:23,410
>> Per eżempju, liema tipi ta 'affarijiet imorru
fuq il-munzell rigward il-

417
00:18:23,410 --> 00:18:27,420
tqassim memorja konna diskussi
fil-ġimgħat li għaddew?

418
00:18:27,420 --> 00:18:28,736
X'hemm li?

419
00:18:28,736 --> 00:18:29,670
>> UDJENZA: Sejħiet għall-funzjonijiet.

420
00:18:29,670 --> 00:18:30,260
>> DAVID Malan: Jien sorry.

421
00:18:30,260 --> 00:18:31,210
>> UDJENZA: Sejħiet għall-funzjonijiet.

422
00:18:31,210 --> 00:18:33,590
>> DAVID Malan: Sejħiet għall-funzjonijiet, iżda
speċifikament, x'hemm ġewwa ta 'kull

423
00:18:33,590 --> 00:18:35,340
dawk frames?

424
00:18:35,340 --> 00:18:37,220
Liema tip ta 'affarijiet?

425
00:18:37,220 --> 00:18:37,460
Yeah.

426
00:18:37,460 --> 00:18:38,500
Allura varjazzjonijiet lokali.

427
00:18:38,500 --> 00:18:43,080
Ghaċ aħna għandna bżonn ftit ħażna lokali,
bħal argument, jew int I, jew int

428
00:18:43,080 --> 00:18:45,940
temperatura, jew kull lokali
varjabbli, aħna kont qed

429
00:18:45,940 --> 00:18:47,210
tpoġġija ta 'dak fuq il-munzell.

430
00:18:47,210 --> 00:18:49,610
U aħna sejħa hija ta 'ċumnija minħabba
ta 'dik l-idea saffi.

431
00:18:49,610 --> 00:18:52,940
Just tip ta 'logħbiet up mar-realtà,
il-kunċett tiegħu.

432
00:18:52,940 --> 00:18:56,650
>> Iżda jirriżulta li munzell jistgħu wkoll
titqies bħala struttura data, l-

433
00:18:56,650 --> 00:19:00,110
alternattiva għal firxa, alternattiva
għal lista marbuta.

434
00:19:00,110 --> 00:19:02,770
Xi ħaġa kunċettwalment aktar interessanti
li xorta tista 'tkun

435
00:19:02,770 --> 00:19:06,030
implimentata bl-użu jew ta 'dawk
affarijiet, imma hija tip differenti ta '

436
00:19:06,030 --> 00:19:09,140
struttura tad-data ta 'sostenn, verament,
biss żewġ operazzjonijiet.

437
00:19:09,140 --> 00:19:11,000
Iżda int tista 'żżid fuq fancier
karatteristiċi minn dawn.

438
00:19:11,000 --> 00:19:12,180
Iżda dawn huma l-baŜi -

439
00:19:12,180 --> 00:19:13,510
timbotta u pop.

440
00:19:13,510 --> 00:19:19,240
>> U l-idea ma 'munzell hija li jekk jien
jkollhom hawn, bi jew mingħajr Annenberg

441
00:19:19,240 --> 00:19:22,880
jafu, trej minn bieb li jmiss
bin-numru 9 fuq dan.

442
00:19:22,880 --> 00:19:23,870
Allura biss int.

443
00:19:23,870 --> 00:19:26,990
U nixtieq li timbotta din fuq id-dejta
istruttura, li bħalissa hija vojta.

444
00:19:26,990 --> 00:19:28,790
Ikkunsidra dan il-qiegħ tal-munzell.

445
00:19:28,790 --> 00:19:33,150
Nixtieq push dan in-numru 9 fuq il-
munzell, u issa huwa hemm dritt.

446
00:19:33,150 --> 00:19:36,040
>> Imma l-ħaġa interessanti dwar munzell
hija li jekk jien issa tixtieq li timbotta

447
00:19:36,040 --> 00:19:40,210
xi valur, bħall 17, u I imbotta
dan fuq il-munzell, jien ser tagħmel

448
00:19:40,210 --> 00:19:43,290
l-unika ħaġa intuwittivi, jien biss ser
biex tpoġġi dan id-dritt fejn aħna bnedmin

449
00:19:43,290 --> 00:19:45,180
ikunu inklinati li tqiegħed lilha, fuq nett.

450
00:19:45,180 --> 00:19:48,850
Imma x'hemm interessanti issa
hija, kif nista 'nikseb fuq 9?

451
00:19:48,850 --> 00:19:50,670
You know, I do mhux mingħajr xi sforz.

452
00:19:50,670 --> 00:19:54,070
>> Allura x'hemm interessanti dwar
munzell huwa li permezz tad-disinn,

453
00:19:54,070 --> 00:19:56,330
huwa struttura data LIFO.

454
00:19:56,330 --> 00:19:59,680
Mod iblah li jiddeskrivu
aħħar, l-ewwel out.

455
00:19:59,680 --> 00:20:03,280
Allura l-aħħar numru fis
f'dan il-ħin kien 17.

456
00:20:03,280 --> 00:20:07,540
Mela jekk jien tixtieq li pop xi ħaġa off
tal-munzell, jista 'jkun biss 17.

457
00:20:07,540 --> 00:20:11,890
Allura hemm ordni obbligatorja ta '
operazzjonijiet hawn, fejn l-aħħar oġġett

458
00:20:11,890 --> 00:20:14,260
fl għandu jkun l-ewwel wieħed out.

459
00:20:14,260 --> 00:20:16,440
Għalhekk l-akronimu, LIFO.

460
00:20:16,440 --> 00:20:19,160
>> Allura għaliex jista 'dan jiġi utli?

461
00:20:19,160 --> 00:20:22,690
Huma kuntesti tagħhom li youd
tixtieq struttura data bħal din?

462
00:20:22,690 --> 00:20:24,810
Ukoll, huwa ċertament kien utli
ġewwa ta 'kompjuter.

463
00:20:24,810 --> 00:20:29,050
Sistemi tantx jaħdmu jużaw dan b'mod ċar
tip ta 'struttura tad-data għall stacks.

464
00:20:29,050 --> 00:20:32,800
Aħna ser tara wkoll l-istess idea
meta niġu għall-paġni web.

465
00:20:32,800 --> 00:20:35,890
Allura din il-ġimgħa u ġimgħa d-dieħla u lil hinn,
u kif inti tibda timplimenta web

466
00:20:35,890 --> 00:20:39,490
paġni f'lingwa msejħa HTML, inti tista '
attwalment jużaw struttura data bħal

467
00:20:39,490 --> 00:20:42,690
dan biex jiddeterminaw jekk il-paġna
huwa formattjati b'mod korrett.

468
00:20:42,690 --> 00:20:47,170
Għaliex aħna ser tara l-paġni web jsegwu
speċi ta 'ġerarkija, indentazzjoni

469
00:20:47,170 --> 00:20:52,030
li se, fl-aħħar tal-ġurnata, ikun
struttura ta 'siġra taħt il-barnuża.

470
00:20:52,030 --> 00:20:53,620
Allura aktar fuq li fi ftit ftit.

471
00:20:53,620 --> 00:20:56,560
>> Iżda għal issa, ejja suġġeriti għal
mument, kif nistgħu tmur dwar

472
00:20:56,560 --> 00:20:58,830
li jirrappreżenta dak munzell hu?

473
00:20:58,830 --> 00:21:03,370
Let me tipproponi li nimplimentaw
munzell bil-kodiċi bħal dan.

474
00:21:03,370 --> 00:21:07,990
Allura munzell hu ser ikollhom ġewwa ta 'dan
żewġ affarijiet, l-firxa, imsejħa trejs,

475
00:21:07,990 --> 00:21:09,510
biss sabiex ikunu konsistenti mal-demo.

476
00:21:09,510 --> 00:21:12,660
U kull wieħed mill-oġġetti f'dak array
se tkun int tip.

477
00:21:12,660 --> 00:21:14,740
U l-kapaċità x'aktarx li huwa dak?

478
00:21:14,740 --> 00:21:18,796
Għaliex stajt ma jkunx miktub il-
definizzjoni sħiħa hawn.

479
00:21:18,796 --> 00:21:21,535
>> Huwa probabbilment l-massimu
daqs tal-array.

480
00:21:21,535 --> 00:21:25,150
U huwa probabbilment ddikjarat bħala sharp
jiddefinixxu fil-quċċata tal-fajl, xi

481
00:21:25,150 --> 00:21:28,450
tip ta 'kostanti kif implikat
is-sempliċi kapitalizzazzjoni.

482
00:21:28,450 --> 00:21:32,250
Allura x'imkien saħħa hija definita
id-daqs massimu possibbli.

483
00:21:32,250 --> 00:21:35,590
Sadanittant, ġewwa tal-istruttura tad-data
magħrufa bħala munzell se jkun hemm

484
00:21:35,590 --> 00:21:38,630
tkun numru sħiħ biss magħrufa
sempliċement bħala daqs.

485
00:21:38,630 --> 00:21:43,400
>> Mela jekk jien kienu jirrappreżentaw dan issa
pictorially, ejja nassumu li din

486
00:21:43,400 --> 00:21:48,070
kaxxa s-sewda kollu jirrappreżenta munzell tiegħi.

487
00:21:48,070 --> 00:21:50,070
Ġewwa ta 'dan huwa ta' żewġ varjabbli.

488
00:21:50,070 --> 00:21:54,780
Hekk jien ser tiġbed l-
ewwel wieħed bħala daqs.

489
00:21:54,780 --> 00:21:57,420
U t-tieni waħda jien ser
biex tiġbed bħala firxa.

490
00:21:57,420 --> 00:22:01,060
>> Iżda biss li żżomm affarijiet ordnat,
normalment I jiġbed firxa bħal

491
00:22:01,060 --> 00:22:04,910
dan, iżda dan l-xorta ta 'sbieħ
jekk aħna logħba realtà, jew

492
00:22:04,910 --> 00:22:06,230
jaqblu mal-mudell mentali.

493
00:22:06,230 --> 00:22:12,880
So let me minflok jiġbed l-array
vertikalment, li huwa biss, għal darb'oħra,

494
00:22:12,880 --> 00:22:13,840
konsenja artist.

495
00:22:13,840 --> 00:22:16,610
Ma verament kwistjoni dak li
huwa taħt il-barnuża.

496
00:22:16,610 --> 00:22:20,350
U aħna ser ngħidu li, awtomatikament,
kapaċità se tkun tlieta.

497
00:22:20,350 --> 00:22:23,480
Allura dan se jkun post 0, dan
se jkun post 1, dan

498
00:22:23,480 --> 00:22:25,740
se jkun post 2.

499
00:22:25,740 --> 00:22:29,330
>> Jekk I jixtru bil-ballun stress, kieku
xi ħadd jixtieq li toħroġ u tmexxi l-

500
00:22:29,330 --> 00:22:30,870
jitla 'abbord hawn għal ftit mument?

501
00:22:30,870 --> 00:22:31,960
OK, raw idejn tiegħek l-ewwel.

502
00:22:31,960 --> 00:22:33,950
Come fuq up.

503
00:22:33,950 --> 00:22:36,500
Kull dritt.

504
00:22:36,500 --> 00:22:38,760
So I jemmnu li huwa Steven.

505
00:22:38,760 --> 00:22:40,035
Come fuq up.

506
00:22:40,035 --> 00:22:40,770
Kull dritt.

507
00:22:40,770 --> 00:22:46,760
>> Imma jissoponi issa aħna Rewind għall-bidu
istat tad-dinja fejn I

508
00:22:46,760 --> 00:22:52,180
għadek iddikjarat munzell, u huwa
se jkun ta 'kapaċità tlieta.

509
00:22:52,180 --> 00:22:54,470
Iżda d-daqs għadu ma ġiex determinat.

510
00:22:54,470 --> 00:22:56,100
Trays għadu ma ġiex determinat.

511
00:22:56,100 --> 00:22:57,300
Allura koppja ta 'mistoqsijiet ewwel.

512
00:22:57,300 --> 00:23:01,310
U let me jagħtuk mic sabiex inti tista '
ikollhom sehem aktar attiv f'dan.

513
00:23:01,310 --> 00:23:05,190
>> Allura dak li hu ġewwa ta 'daqs f'dan il-mument
fil-ħin jekk I kollha għamlu huwa

514
00:23:05,190 --> 00:23:09,340
iddikjarata munzell ma
linja waħda tal-kodiċi?

515
00:23:09,340 --> 00:23:10,100
>> STEVEN: Mhux ħafna.

516
00:23:10,100 --> 00:23:12,080
>> DAVID Malan: OK, mhux wisq.

517
00:23:12,080 --> 00:23:14,410
Nafu x'hemm ġewwa ta 'daqs,
nafu x'hemm ġewwa

518
00:23:14,410 --> 00:23:16,330
ta 'dan array hawn?

519
00:23:16,330 --> 00:23:18,630
>> STEVEN: kodiċi Just każwali, right?

520
00:23:18,630 --> 00:23:20,220
Just -

521
00:23:20,220 --> 00:23:23,230
>> DAVID Malan: Yeah, jien ser
sejħa hija kodiċi, iżda każwali -

522
00:23:23,230 --> 00:23:23,820
>> STEVEN: Things.

523
00:23:23,820 --> 00:23:28,290
>> DAVID Malan: Affarijiet simili każwali

524
00:23:28,290 --> 00:23:28,870
>> STEVEN: Bits.

525
00:23:28,870 --> 00:23:29,530
>> DAVID Malan: Bits, right?

526
00:23:29,530 --> 00:23:31,190
Allura valuri taż-żibel, id-dritt?

527
00:23:31,190 --> 00:23:33,470
Allura permutazzjonijiet ta 'l-0 u 1 ta.

528
00:23:33,470 --> 00:23:35,920
Fdalijiet ta 'użanzi ta' qabel
ta 'dan il-memorja.

529
00:23:35,920 --> 00:23:38,150
U aħna ma verament jafu liema l-valuri
huma, hekk aħna tipikament tiġbed minnhom

530
00:23:38,150 --> 00:23:38,930
bħala trade marks in kwistjoni.

531
00:23:38,930 --> 00:23:41,990
>> Allura l-ewwel ħaġa li għandna qed preżumibbilment
tmur jridu nagħmlu hawnhekk -

532
00:23:41,990 --> 00:23:46,630
u let me jagħtu f'dan il-qasam ġewwa
li jkun hemm l-isem - trays.

533
00:23:46,630 --> 00:23:49,540
X'għandu aħna preżumibbilment initialize
daqs għal jekk irridu

534
00:23:49,540 --> 00:23:51,040
tibda tuża din munzell?

535
00:23:51,040 --> 00:23:53,070
>> STEVEN: Tray huwa sub 3.

536
00:23:53,070 --> 00:23:53,910
>> DAVID Malan: Allura, OK.

537
00:23:53,910 --> 00:23:56,710
Biex ikunu ċari, il-kapaċità hija dikjarata
f'postijiet oħra kif tlieta.

538
00:23:56,710 --> 00:23:58,570
U dan huwa dak li stajt użati
li jallokaw l-array.

539
00:23:58,570 --> 00:24:03,535
Daqs se jirreferu għal kemm
trejs huma bħalissa fuq il-munzell.

540
00:24:03,535 --> 00:24:03,880
>> STEVEN: Zero.

541
00:24:03,880 --> 00:24:04,460
>> DAVID Malan: Għalhekk għandu jkun żero.

542
00:24:04,460 --> 00:24:07,760
Allura aqbad, u ma 'kwalunkwe finger,
jiġbed żero fid-daqs.

543
00:24:07,760 --> 00:24:08,440
Kull dritt.

544
00:24:08,440 --> 00:24:10,920
Allura issa, x'hemm ġewwa ta 'dan
hawn, ma nafux.

545
00:24:10,920 --> 00:24:12,160
Dawn huma verament valuri taż-żibel biss.

546
00:24:12,160 --> 00:24:14,800
Allura aħna jista 'jiġbed trade marks in kwistjoni, iżda
ejja iżommu l-bord nadif għal issa

547
00:24:14,800 --> 00:24:16,300
għaliex ma jimpurtax
x'hemm hemmhekk.

548
00:24:16,300 --> 00:24:19,130
Aħna ma bżonn li initialize-firxa
għal xejn, għaliex jekk aħna nafu li

549
00:24:19,130 --> 00:24:23,100
id-daqs tal-munzell huwa żero, ukoll, aħna
m'għandhomx ikunu tħares lejn xejn fil

550
00:24:23,100 --> 00:24:25,590
din array xorta waħda fuq
dan il-punt fil-ħin.

551
00:24:25,590 --> 00:24:29,970
>> Allura issa I jissoponi li timbotta l-
numru 9 fuq il-munzell.

552
00:24:29,970 --> 00:24:33,750
Kif nistgħu taġġorna l-istruttura tad-data
ġewwa ta 'din il-kaxxa sewda?

553
00:24:33,750 --> 00:24:35,540
Dak valuri bżonn għall-bidla?

554
00:24:35,540 --> 00:24:36,200
>> STEVEN: Fi -

555
00:24:36,200 --> 00:24:37,400
id-daqs?

556
00:24:37,400 --> 00:24:37,650
>> DAVID Malan: OK.

557
00:24:37,650 --> 00:24:38,770
Daqs għandu jsir dak?

558
00:24:38,770 --> 00:24:39,580
>> STEVEN: Daqs tkun waħda.

559
00:24:39,580 --> 00:24:39,870
>> DAVID Malan: OK.

560
00:24:39,870 --> 00:24:41,110
Allura daqs għandha ssir waħda.

561
00:24:41,110 --> 00:24:42,540
Allura inti tista 'tagħmel dan fil-modi koppja.

562
00:24:42,540 --> 00:24:46,920
Ħalli nagħtikom, issa tiegħek
saba huwa Eraser.

563
00:24:46,920 --> 00:24:47,260
Kull dritt.

564
00:24:47,260 --> 00:24:49,960
Allura issa finger tiegħek huwa brush.

565
00:24:49,960 --> 00:24:50,330
Kull dritt.

566
00:24:50,330 --> 00:24:52,820
U issa x'iktar għandha tinbidel,
ovvjament, fl-istruttura tad-data?

567
00:24:52,820 --> 00:24:57,060
>> STEVEN: Aħna qed tmur minn
bottom up sa 9.

568
00:24:57,060 --> 00:24:57,760
>> DAVID Malan: 9.

569
00:24:57,760 --> 00:24:58,420
OK, Good.

570
00:24:58,420 --> 00:25:01,550
Allura xorta ma jimpurtax x'hemm fuq
post wieħed jew tnejn għaliex qed

571
00:25:01,550 --> 00:25:04,520
Valuri taż-żibel, imma aħna ma għandhom jolqot
tfittex hemmhekk minħabba d-daqs huwa

572
00:25:04,520 --> 00:25:07,540
tgħidilna li biss l-ewwel element
huwa attwalment leġittimu.

573
00:25:07,540 --> 00:25:10,400
Allura issa I imbotta 17 fuq il-lista.

574
00:25:10,400 --> 00:25:11,830
X'jiġri din l-istampa?

575
00:25:11,830 --> 00:25:14,720
>> STEVEN: Allura daqs huwa se jmorru għal tnejn.

576
00:25:14,720 --> 00:25:15,300
>> DAVID Malan: OK.

577
00:25:15,300 --> 00:25:16,070
Inti Eraser -

578
00:25:16,070 --> 00:25:16,810
oops.

579
00:25:16,810 --> 00:25:18,026
Int Eraser.

580
00:25:18,026 --> 00:25:18,840
>> STEVEN: Eraser.

581
00:25:18,840 --> 00:25:19,720
>> DAVID Malan: Inti brush.

582
00:25:19,720 --> 00:25:20,560
>> STEVEN: xkupilja.

583
00:25:20,560 --> 00:25:20,920
>> DAVID Malan: OK.

584
00:25:20,920 --> 00:25:21,600
U x'iktar?

585
00:25:21,600 --> 00:25:22,600
>> STEVEN: U allura aħna -

586
00:25:22,600 --> 00:25:22,915
>> DAVID Malan: Aħna imbuttat 17.

587
00:25:22,915 --> 00:25:24,760
>> STEVEN: Aħna nimxu 17 fuq, hekk -

588
00:25:24,760 --> 00:25:25,710
>> DAVID Malan: OK, tajba.

589
00:25:25,710 --> 00:25:27,040
>> STEVEN: - qatra l-isfel.

590
00:25:27,040 --> 00:25:27,530
>> DAVID Malan: Kull dritt.

591
00:25:27,530 --> 00:25:27,940
Huwa jkollna faċli.

592
00:25:27,940 --> 00:25:29,300
Jien ma jmur biex jgħinek dan iż-żmien.

593
00:25:29,300 --> 00:25:30,510
Imbotta 22.

594
00:25:30,510 --> 00:25:31,720
>> STEVEN: Magħmul.

595
00:25:31,720 --> 00:25:34,870
Issir Eraser.

596
00:25:34,870 --> 00:25:37,340
Jien issir brush.

597
00:25:37,340 --> 00:25:39,340
U mbagħad I am tqegħid 22.

598
00:25:39,340 --> 00:25:40,100
>> DAVID Malan: 22.

599
00:25:40,100 --> 00:25:40,620
Eċċellenti.

600
00:25:40,620 --> 00:25:41,380
Allura wieħed aktar ħin.

601
00:25:41,380 --> 00:25:44,280
Jien issa ser timbotta
fuq il-munzell 26.

602
00:25:44,280 --> 00:25:46,350
>> STEVEN: Ooh.

603
00:25:46,350 --> 00:25:50,278
Oh gosh.

604
00:25:50,278 --> 00:25:52,520
Int verament maqbuda me off guard.

605
00:25:52,520 --> 00:25:53,703
>> DAVID Malan: Inti ma
tara dan ġejjin?

606
00:25:53,703 --> 00:25:55,930
>> STEVEN: I ma tara dan ġejjin.

607
00:25:55,930 --> 00:25:58,756
Nistgħu kapaċità jerġgħu inizjali?

608
00:25:58,756 --> 00:25:59,790
>> DAVID Malan: Dik hija mistoqsija tajba.

609
00:25:59,790 --> 00:26:02,360
Allura konna tip ta 'miżbugħa nfusna
fil-kantuniera hawn.

610
00:26:02,360 --> 00:26:06,740
M'hemm l-ebda verament out tajba għall Steven
għaliex aħna ħadthom allokat dan array

611
00:26:06,740 --> 00:26:09,130
statikament, biex ngħidu hekk, ġewwa
tal-istruttura tad-data.

612
00:26:09,130 --> 00:26:12,170
U konna essenzjalment hard kodifikati
li jkun ta 'daqs tlieta.

613
00:26:12,170 --> 00:26:14,170
Allura ma nistgħux verament jallokah.

614
00:26:14,170 --> 00:26:20,020
>> Nistgħu jekk aħna marru lura fi, aħna
definiti mill-ġdid trejs li tkun pointer li

615
00:26:20,020 --> 00:26:22,300
aħna mbagħad jużaw malloc għall-memorja idejn biex.

616
00:26:22,300 --> 00:26:25,050
Għaliex jekk aħna ltqajna l-memorja minn
-munzell permezz malloc, aħna

617
00:26:25,050 --> 00:26:26,430
allura tista 'jeħles minnu.

618
00:26:26,430 --> 00:26:29,630
Iżda qabel ħelsien dan, nistgħu
jirriallokaw blokki akbar ta 'memorja,

619
00:26:29,630 --> 00:26:31,330
taġġorna l-pointer, u oħrajn.

620
00:26:31,330 --> 00:26:33,500
Iżda għal issa, dan huwa verament
l-aħjar li nistgħu nagħmlu.

621
00:26:33,500 --> 00:26:36,360
Imbotta u pop huma preżumibbilment tmur
li jkollhom mmarkati xi żball.

622
00:26:36,360 --> 00:26:40,270
>> Allura per eżempju, l-implimentazzjoni tagħna
ta 'push tista tirritorna bool li

623
00:26:40,270 --> 00:26:42,390
lura qabel vera, vera, vera.

624
00:26:42,390 --> 00:26:48,390
Iżda l-raba 'darba, li għaddej biex ikollhom
li jirritornaw foloz, per eżempju.

625
00:26:48,390 --> 00:26:48,540
Kull dritt.

626
00:26:48,540 --> 00:26:49,540
Ħafna isir ukoll.

627
00:26:49,540 --> 00:26:50,060
Prosit.

628
00:26:50,060 --> 00:26:52,160
You ħadthom qalgħu ballun stress tiegħek illum.

629
00:26:52,160 --> 00:26:53,110
>> [Applause]

630
00:26:53,110 --> 00:26:54,382
>> STEVEN: Grazzi.

631
00:26:54,382 --> 00:26:55,680
>> DAVID Malan: Grazzi.

632
00:26:55,680 --> 00:26:59,740
OK, sabiex dan jidher li mhux wisq
ta 'pass' il quddiem, id-dritt?

633
00:26:59,740 --> 00:27:01,410
Aħna deskritti din l-istruttura tad-data.

634
00:27:01,410 --> 00:27:02,320
Huwa kien konvinċenti, right?

635
00:27:02,320 --> 00:27:03,200
Sistemi operattivi bhalu.

636
00:27:03,200 --> 00:27:06,360
Apparentement il-web tista 'tagħmel użu ta' dan,
u applikazzjonijiet oħra għadhom.

637
00:27:06,360 --> 00:27:10,870
Imma dak limitazzjoni stupid li aħna qed
lura għall tip ta 'ġimgħa żewġ limiti

638
00:27:10,870 --> 00:27:12,880
fejn għandna fissi arrays daqs.

639
00:27:12,880 --> 00:27:15,010
>> Allura hemm tabilħaqq huma koppja ta '
modi nistgħu issolvi din.

640
00:27:15,010 --> 00:27:18,750
Nistgħu dinamikament jallokaw il-firxa,
mhux billi hard kodifika bħala stajt

641
00:27:18,750 --> 00:27:22,600
jsir hawn, iżda minflok li tiddikjara mill-ġdid
dan, biss li tkun ċara, kif

642
00:27:22,600 --> 00:27:23,830
xi ħaġa bħal din.

643
00:27:23,830 --> 00:27:29,040
Int * trejs, mhux deċiż
fuq kapaċità s'issa.

644
00:27:29,040 --> 00:27:35,460
Imma meta I jiddikjara l-munzell x'imkien ieħor
fil-kodiċi tiegħi, I jistgħu mbagħad is-sejħa malloc,

645
00:27:35,460 --> 00:27:38,250
jiksbu l-indirizz ta 'blokki ta'
memorja, u I jistgħu jassenjaw

646
00:27:38,250 --> 00:27:39,980
dak l-indirizz għall-trejs.

647
00:27:39,980 --> 00:27:43,340
>> U mbagħad, għaliex huwa biss blokki ta '
memorja, I jistgħu jkomplu jużaw kwadri

648
00:27:43,340 --> 00:27:45,450
notazzjoni bracket bil-mod normali.

649
00:27:45,450 --> 00:27:49,020
Minħabba darb'oħra, hemm tip ta 'dan
ekwivalenti funzjonali ta 'arrays u

650
00:27:49,020 --> 00:27:50,820
biċċiet ta 'memorja li ġejjin
lura mill malloc.

651
00:27:50,820 --> 00:27:53,090
Nistgħu jittrattaw lil bħall-oħra
użu aritmetika pointer jew

652
00:27:53,090 --> 00:27:54,440
notazzjoni bracket kwadru.

653
00:27:54,440 --> 00:27:55,660
Allura dak l-approċċ wieħed.

654
00:27:55,660 --> 00:28:00,120
>> Imma kif inkella jista nimplimentaw dan
struttura tad-data istess, potenzjalment?

655
00:28:00,120 --> 00:28:00,280
Dritt?

656
00:28:00,280 --> 00:28:04,530
Inħoss bħal aħna biss solvuta din
problema bħal ġimgħa ilu.

657
00:28:04,530 --> 00:28:08,860
Liema kienet l-soluzzjoni għal din il-problema
li Steven dam fis?

658
00:28:08,860 --> 00:28:10,370
Listi Allura marbuta, id-dritt.

659
00:28:10,370 --> 00:28:13,410
>> Jekk il-problema hija li aħna qed pittura
lilna nfusna fis-kantuniera billi jallokaw

660
00:28:13,410 --> 00:28:17,580
bil-quddiem memorja ftit wisq li aħna
mbagħad ikollhom li b'xi mod jittrattaw, ukoll,

661
00:28:17,580 --> 00:28:19,880
għaliex mhux biss evitat li
joħroġ għal kollox?

662
00:28:19,880 --> 00:28:26,170
Għaliex mhux biss tiddikjara trejs biex tkun
pointer għal node, ergo lista marbuta,

663
00:28:26,170 --> 00:28:30,740
u mbagħad sempliċement talloka lymph ġodda
kull darba Steven meħtieġ biex jitwaħħal

664
00:28:30,740 --> 00:28:32,400
numru fl-istruttura tad-data.

665
00:28:32,400 --> 00:28:34,200
>> Allura l-istampa jkollha għall-bidla.

666
00:28:34,200 --> 00:28:38,220
Huwa mhux ser tkun nadifa u bħala
sempliċi kemm biss firxa ta 'tliet ints.

667
00:28:38,220 --> 00:28:42,970
Issa li għaddej biex tkun pointer għal
Struct, u li Struct se

668
00:28:42,970 --> 00:28:44,830
ikollhom int u werrej li jmiss.

669
00:28:44,830 --> 00:28:47,670
Huwa ser twassal permezz ta 'dak pointer
li Struct ieħor tali

670
00:28:47,670 --> 00:28:48,600
Struct oħra bħal din.

671
00:28:48,600 --> 00:28:50,560
Allura l-istampa fil-fatt
jiksbu Messier daqsxejn.

672
00:28:50,560 --> 00:28:52,950
U aħna'd jkollhom vleġeġ irbit
kollox flimkien.

673
00:28:52,950 --> 00:28:55,280
>> Iżda li l-multa, id-dritt, għaliex
Rajna kif għandek tagħmel dan.

674
00:28:55,280 --> 00:28:58,180
U ladarba inti tikseb komda
xi ħaġa implimentazzjoni bħal linked

675
00:28:58,180 --> 00:29:01,450
lista, li inti ser ikollok tagħmel jekk inti
jagħżlu li jimplimentaw tabella hash ma

676
00:29:01,450 --> 00:29:05,120
chaining separata għal p-set 6, inti tista '
jużawha bħala blokk bini, jew

677
00:29:05,120 --> 00:29:08,870
ingredjent, jew Scratch jitkellmu, a
proċedura, xi ħaġa li inti tpoġġi, inti

678
00:29:08,870 --> 00:29:12,560
maħluqa biċċa tiegħek puzzle stess
li inti tista 'mbagħad użu mill-ġdid.

679
00:29:12,560 --> 00:29:17,090
Kompromessi hekk, imma soluzzjonijiet potenzjali
li konna fil-fatt rajna qabel.

680
00:29:17,090 --> 00:29:20,560
>> Allura ħafna drabi, inti tara dan kull
sena jew tnejn meta rilaxxi Apple

681
00:29:20,560 --> 00:29:23,060
xi ħaġa ġdida, u l-poplu crazy
line up barra tal-Apple

682
00:29:23,060 --> 00:29:27,050
taħżen jixtru marġinali tagħhom
upgrade fuq il-hardware.

683
00:29:27,050 --> 00:29:30,420
Jien ngħid dan, huwa OK, għaliex
Jiena wieħed minn dawk in-nies.

684
00:29:30,420 --> 00:29:35,140
Allura liema tip ta 'struttura data
jafu jirrappreżentaw din ir-realtà?

685
00:29:35,140 --> 00:29:36,980
>> Well, ejja sejħa hija ta 'kju, linja.

686
00:29:36,980 --> 00:29:40,270
Allura British sejħa hija tipikament
kju xorta, dan huwa isem sbieħ.

687
00:29:40,270 --> 00:29:44,960
U ż-żewġ operazzjonijiet li kju
għandha tappoġġa aħna ser sejħa enqueue

688
00:29:44,960 --> 00:29:48,900
operazzjoni u operazzjoni dequeue,
li huma simili fil-

689
00:29:48,900 --> 00:29:50,120
ispirtu biex timbotta u pop.

690
00:29:50,120 --> 00:29:54,060
Huwa biss tip ta 'differenti
konvenzjoni, dak li aħna qed titlob dawn.

691
00:29:54,060 --> 00:29:57,680
Iżda biex enqueue xi ħaġa mezzi biex iżżid
jew daħħal għall-istruttura tad-data.

692
00:29:57,680 --> 00:29:59,570
Biex dequeue mezzi biex tneħħiha.

693
00:29:59,570 --> 00:30:05,170
Iżda billi munzell kien data LIFO
istruttura, kju hija l-ewwel fi,

694
00:30:05,170 --> 00:30:06,740
ewwel out istruttura tad-data.

695
00:30:06,740 --> 00:30:10,050
>> Jekk inti l-ewwel persuna fil-linja,
inti se tkun l-ewwel persuna li tikseb

696
00:30:10,050 --> 00:30:12,420
barra tal-linja u jixtru tagħmir ġdid tiegħek.

697
00:30:12,420 --> 00:30:18,070
Immaġina kif mqalleb dawn in-nies ikunu
jekk Apple minflok tintuża 'ċumnija, għal

698
00:30:18,070 --> 00:30:21,250
Pereżempju, biex jimplimentaw il-picking
up ta 'ġugarell ġdida tiegħek.

699
00:30:21,250 --> 00:30:24,310
Allura kjuwijiet jagħmel sens, ċertament, u
nistgħu naħsbu ta 'kull xorta ta'

700
00:30:24,310 --> 00:30:27,480
applikazzjonijiet, preżumibbilment, għal kjuwijiet,
speċjalment meta inti tixtieq ġustizzja.

701
00:30:27,480 --> 00:30:30,040
Allura kif tista 'nimplimentaw dawn
bħala struttura data?

702
00:30:30,040 --> 00:30:33,680
>> Well, nipproponi li aħna jistgħu
bżonn tagħmel dan il-mod.

703
00:30:33,680 --> 00:30:35,225
Hekk jien ser issa għandhom numri.

704
00:30:35,225 --> 00:30:38,190
Allura aħna ser jżommha sempliċi u mhux
neċessarjament jitkellmu f'termini ta 'dixxijiet.

705
00:30:38,190 --> 00:30:40,220
Just numri li n-nies ta gotten.

706
00:30:40,220 --> 00:30:43,760
Kapaċità se, għal darb'oħra, tiffissa l-
numru totali ta 'nies li jistgħu jkunu fil-

707
00:30:43,760 --> 00:30:46,900
din il-linja, bħala tlieta jew
x'ikun oħra valur.

708
00:30:46,900 --> 00:30:50,760
>> Imma jiena nipproponi li għandi bżonn li jżommu rekord
mhux biss tad-daqs tal-

709
00:30:50,760 --> 00:30:52,370
kju, affarijiet kemm huma fiha.

710
00:30:52,370 --> 00:30:56,310
Allura daqs huwa d-daqs attwali, il-kapaċità
huwa d-daqs massimu.

711
00:30:56,310 --> 00:30:58,540
Just mill-ġdid, in-nomenklatura
minn konvenzjoni.

712
00:30:58,540 --> 00:31:03,680
Għaliex għandi bżonn int addizzjonali ġewwa
ta 'kju biex iżżomm kont ta' min huwa fil-

713
00:31:03,680 --> 00:31:05,365
quddiem tal-linja?

714
00:31:05,365 --> 00:31:07,930

715
00:31:07,930 --> 00:31:10,910
Għaliex għandi bżonn li tagħmel dan f'dan il-każ?

716
00:31:10,910 --> 00:31:14,750

717
00:31:14,750 --> 00:31:16,190
>> Well, kif huwa din l-istampa
se jibdlu?

718
00:31:16,190 --> 00:31:19,280
I tista 'probabbilment użu mill-ġdid aktar
ta 'din l-istampa.

719
00:31:19,280 --> 00:31:21,480
Let me imorru quddiem u tħassar x'hemm hawn.

720
00:31:21,480 --> 00:31:24,580
Aħna ser tagħti dan ftit
isem differenti up here.

721
00:31:24,580 --> 00:31:28,930
Ejja jeħles mill-17, ejja jeħles
tal-9, ejja jeħles mill-3.

722
00:31:28,930 --> 00:31:30,410
U ejja żid ħaġa waħda oħra.

723
00:31:30,410 --> 00:31:34,710
Nipproponi li għandi bżonn biex iżżomm kont ta '
quddiem tal-lista, li huwa biss

724
00:31:34,710 --> 00:31:35,570
se tkun int ukoll.

725
00:31:35,570 --> 00:31:36,550
U aħna qed tmur biex jżommha sempliċi.

726
00:31:36,550 --> 00:31:37,740
Nru lista marbuta għal issa.

727
00:31:37,740 --> 00:31:40,900
>> Aħna ser jammettu li aħna qed tmur biex
bump up kontra dan il-limitu.

728
00:31:40,900 --> 00:31:43,720
Imma dak li nixtieq li tara
jiġri dan iż-żmien?

729
00:31:43,720 --> 00:31:47,240
So I jissoponi aqbad u l-ewwel
persuna tkun fil-linja, u

730
00:31:47,240 --> 00:31:48,560
huwa n-numru 9.

731
00:31:48,560 --> 00:31:49,680
We do jkollhom blalen istress.

732
00:31:49,680 --> 00:31:51,330
Nista steal, ngħidu aħna, tnejn jew tliet persuni?

733
00:31:51,330 --> 00:31:52,690
Wieħed, tnejn, tlieta?

734
00:31:52,690 --> 00:31:53,120
Come fuq up.

735
00:31:53,120 --> 00:31:56,022
Dritt minn quddiem, għaliex
aħna ser jagħmlu dan wieħed malajr.

736
00:31:56,022 --> 00:31:59,415
>> Kull wieħed inti issa se tkun
tifel fan fil-linja fil Apple.

737
00:31:59,415 --> 00:32:03,970

738
00:32:03,970 --> 00:32:06,210
Inti mhux se jkun jirċievu Apple hardware
fl-aħħar ta 'dan għalkemm.

739
00:32:06,210 --> 00:32:06,500
Kull dritt.

740
00:32:06,500 --> 00:32:09,430
Allura int numru 9, int
numru 17, numru 22.

741
00:32:09,430 --> 00:32:12,130
Dawn huma numri arbitrarji, bħal
student IDs jew whatnot.

742
00:32:12,130 --> 00:32:14,550
U fi ftit mument, ejja tibda
biex tibda żżid affarijiet.

743
00:32:14,550 --> 00:32:16,000
U jien ser imexxu l-bord hawn dan iż-żmien.

744
00:32:16,000 --> 00:32:19,570
>> Allura f'dan il-każ, stajt initialized
quddiem li tkun -

745
00:32:19,570 --> 00:32:22,380
I attwalment ma verament kura dak l-
quddiem huwa, minħabba d-daqs huwa żero.

746
00:32:22,380 --> 00:32:24,480
Allura dan tista 'ukoll biss
tkun kwistjoni mark.

747
00:32:24,480 --> 00:32:26,170
Dawn huma kollha trade marks in kwistjoni.

748
00:32:26,170 --> 00:32:29,880
Allura issa aħna ser tibda attwalment tara xi
nies lining up fil-maħżen.

749
00:32:29,880 --> 00:32:33,320
>> Mela jekk numru 9, int l-ewwel waħda
hemm fil 5:00, imorru quddiem u line up,

750
00:32:33,320 --> 00:32:34,210
jew il-lejl ta 'qabel.

751
00:32:34,210 --> 00:32:34,580
OK.

752
00:32:34,580 --> 00:32:35,940
Allura issa 9 huwa hawnhekk.

753
00:32:35,940 --> 00:32:37,940
Allura 9 huwa quddiem tal-lista.

754
00:32:37,940 --> 00:32:41,440
Hekk jien ser jimxi 'l quddiem u taġġorna
id-daqs ta din id-data attwali

755
00:32:41,440 --> 00:32:44,740
istruttura li ma jkunux 0 jibqgħalu,
iżda li tkun 1.

756
00:32:44,740 --> 00:32:47,630
Jien ser tpoġġi 9 fil-
quddiem tal-lista.

757
00:32:47,630 --> 00:32:51,020
Let me imorru quddiem u toggle l-iskrin
hekk nistgħu naraw passat us hawn.

758
00:32:51,020 --> 00:32:53,220
>> U issa dak li nixtieq
biex fuq quddiem?

759
00:32:53,220 --> 00:32:56,240
Jien ser iżommu kont li l-
quddiem tal-kju dritt issa

760
00:32:56,240 --> 00:32:58,570
huwa fil-post 0.

761
00:32:58,570 --> 00:33:00,510
Għaliex dak li hu jmiss jiġri?

762
00:33:00,510 --> 00:33:03,000
Ukoll, ejja ngħidu issa I enqueue
17 ukoll.

763
00:33:03,000 --> 00:33:04,510
Allura ħops fil-linja hemmhekk.

764
00:33:04,510 --> 00:33:07,060
U għal darb'oħra, il-tip ta bieb għall-
maħżen se jkun hawn.

765
00:33:07,060 --> 00:33:08,700
Allura issa stajt miżjud 17.

766
00:33:08,700 --> 00:33:10,810
U anki jekk dawn guys huma imblukkar
l-iskrin, li OK,

767
00:33:10,810 --> 00:33:12,300
għaliex nistgħu naraw it up here.

768
00:33:12,300 --> 00:33:12,910
Jiddispjacini.

769
00:33:12,910 --> 00:33:13,810
>> UDJENZA: Nistgħu jiċċaqalqu -

770
00:33:13,810 --> 00:33:14,660
>> DAVID Malan: Le, li OK.

771
00:33:14,660 --> 00:33:16,000
Huwa enormi up hemm.

772
00:33:16,000 --> 00:33:18,580
Allura 17 issa huwa ġewwa tal-kju.

773
00:33:18,580 --> 00:33:21,332
I bżonn jaġġornaw li
oqsma issa għalkemm?

774
00:33:21,332 --> 00:33:23,210
OK, definittivament daqs.

775
00:33:23,210 --> 00:33:26,430
U kif madwar quddiem?

776
00:33:26,430 --> 00:33:27,040
OK, l-ebda.

777
00:33:27,040 --> 00:33:30,200
Front m'għandux jinbidel, għax
b'differenza munzell, aħna

778
00:33:30,200 --> 00:33:31,370
tixtieq li tinżamm l-ġustizzja.

779
00:33:31,370 --> 00:33:35,150
Mela jekk 9 daħal fl-ewwel, irridu 9
tkun l-ewwel barra tal-linja

780
00:33:35,150 --> 00:33:36,420
u fil-maħżen.

781
00:33:36,420 --> 00:33:37,220
>> Fil-fatt, ejja ara dak.

782
00:33:37,220 --> 00:33:42,235
Qabel ma aħna daħħal 22, ejja
imorru quddiem u dequeue 9.

783
00:33:42,235 --> 00:33:42,970
X'hemm isem tiegħek mill-ġdid?

784
00:33:42,970 --> 00:33:43,680
>> UDJENZA: Jake.

785
00:33:43,680 --> 00:33:45,440
>> DAVID Malan: Jake se
li għandha dequeued issa.

786
00:33:45,440 --> 00:33:48,050
Allura ikollok biex jimxu fil-maħżen.

787
00:33:48,050 --> 00:33:49,880
U nippretendu li l-maħżen
huwa hemmhekk.

788
00:33:49,880 --> 00:33:51,970
Allura issa dak li jeħtieġ - dit-dit-dit!

789
00:33:51,970 --> 00:33:53,400
Dak li jeħtieġ li jiġri issa?

790
00:33:53,400 --> 00:33:54,490
Deċiżjoni disinn.

791
00:33:54,490 --> 00:33:56,825
Allura mhux istint ħażina, iżda -
dak l-isem tiegħek mill-ġdid?

792
00:33:56,825 --> 00:33:57,090
>> UDJENZA: David.

793
00:33:57,090 --> 00:33:57,500
>> DAVID Malan: David.

794
00:33:57,500 --> 00:33:58,810
Allura dak li ma David tagħmel?

795
00:33:58,810 --> 00:34:02,590
Huwa kien qed jipprova biex issolvi tad tiffissa d-data
istruttura u jimxu minn post tiegħu

796
00:34:02,590 --> 00:34:04,100
fis lokalità preċedenti Jake.

797
00:34:04,100 --> 00:34:06,740
U li l-multa jekk aħna qed lesti
li jaċċetta li bħala

798
00:34:06,740 --> 00:34:08,199
dettall implimentazzjoni.

799
00:34:08,199 --> 00:34:11,100
Iżda l-ewwel, ejja jaġġornaw l-informazzjoni
istruttura qabel nagħmlu dan.

800
00:34:11,100 --> 00:34:14,139
Għaliex jien ma Predisposizzjoni l-idea ta 'kulħadd
il-poplu ċaqliq fil-linja.

801
00:34:14,139 --> 00:34:17,360
>> Huwa no big deal jekk David ma dan ma
pass wieħed, iżda għal darb'oħra, jaħsbu lura

802
00:34:17,360 --> 00:34:20,360
meta aħna kellna tmien voluntiera fuq l-
istadju u aħna ghamilt like inserzjoni

803
00:34:20,360 --> 00:34:22,600
sort, fejn kellna biex tibda
jiċċaqalqu kulħadd madwar.

804
00:34:22,600 --> 00:34:23,790
Li ltqajna għaljin, right?

805
00:34:23,790 --> 00:34:28,330
Li jagħmel me cringe dwar big O
ta 'ln, big O ta' n kwadrat mill-ġdid.

806
00:34:28,330 --> 00:34:30,650
Mhuwiex sensazzjoni bħal
riżultat ideali.

807
00:34:30,650 --> 00:34:32,080
>> Mela ejja taġġorna dan biss.

808
00:34:32,080 --> 00:34:35,120
Allura l-daqs tal-kju
m'għadux 2.

809
00:34:35,120 --> 00:34:37,090
Huwa issa sempliċiment 1.

810
00:34:37,090 --> 00:34:40,360
Imma I issa tista 'taġġorna xi ħaġa
I ma taġġorna qabel, il-

811
00:34:40,360 --> 00:34:41,130
quddiem tal-lista.

812
00:34:41,130 --> 00:34:45,420
I tista 'biss jgħidu, huwa li post 1?

813
00:34:45,420 --> 00:34:49,770
Allura issa għandna valur żibel hawn,
valur żibel hawn, u David fil-

814
00:34:49,770 --> 00:34:51,469
nofs ta 'dan żibel.

815
00:34:51,469 --> 00:34:54,980
Iżda l-istruttura tad-data
hija għadhom intatti.

816
00:34:54,980 --> 00:34:58,540
>> U fil-fatt, jien ma anki ħtieġa li
jibdlu n-numru ex Jake

817
00:34:58,540 --> 00:35:00,460
9, minħabba quién.

818
00:35:00,460 --> 00:35:04,470
I jkollhom biżżejjed informazzjoni issa fil-
daqs li naf hemm persuna waħda

819
00:35:04,470 --> 00:35:05,030
dan kju.

820
00:35:05,030 --> 00:35:08,340
U naf li dik il-persuna
huwa fil-post 1, ma 0.

821
00:35:08,340 --> 00:35:09,760
Jien ma tingħadd.

822
00:35:09,760 --> 00:35:11,300
Allura 1 ukoll.

823
00:35:11,300 --> 00:35:13,410
Allura l-istruttura tad-data għadu OK.

824
00:35:13,410 --> 00:35:14,330
>> Ukoll, dak li jiġri li jmiss?

825
00:35:14,330 --> 00:35:15,010
Ejja enqueue -

826
00:35:15,010 --> 00:35:15,370
dak l-isem tiegħek?

827
00:35:15,370 --> 00:35:16,160
>> UDJENZA: Callen.

828
00:35:16,160 --> 00:35:16,580
>> DAVID Malan: Callen.

829
00:35:16,580 --> 00:35:20,770
Ejja enqueue a Callen, u
22 issa hija fil-kju.

830
00:35:20,770 --> 00:35:22,300
Allura issa dak li għandu jinbidel hawn?

831
00:35:22,300 --> 00:35:24,380
Front mhux se
bidla, ovvjament.

832
00:35:24,380 --> 00:35:27,160
Id-daqs huwa se jibdlu li jkun 2 għal darb'oħra.

833
00:35:27,160 --> 00:35:31,590
U 22 jispiċċa hawn, 9 għadu preżenti,
imma hija effettivament

834
00:35:31,590 --> 00:35:32,600
valur żibel issa.

835
00:35:32,600 --> 00:35:35,910
Huwa biss fdal ta 'Jake passat.

836
00:35:35,910 --> 00:35:39,200
>> Allura issa x'jiġri jekk
I dequeue David?

837
00:35:39,200 --> 00:35:41,560
Waħda mill-aħħar operazzjoni, dequeue David.

838
00:35:41,560 --> 00:35:46,070
Aħna jista 'jċaqlaq, imma jiena nipproponi ejja
do bħala xogħol inqas possibbli.

839
00:35:46,070 --> 00:35:50,280
Issa struttura tad-data tiegħi tmur
lura fid-daqs 2-1.

840
00:35:50,280 --> 00:35:53,730
Iżda l-quddiem tal-kju
issa jsir 2.

841
00:35:53,730 --> 00:35:56,640
I m'għandhomx bżonn li tibdel dawn in-numri
għadha biss, għaliex qed

842
00:35:56,640 --> 00:35:58,230
Valuri taż-żibel biss.

843
00:35:58,230 --> 00:35:59,720
>> Imma issa x'jiġri?

844
00:35:59,720 --> 00:36:03,280
Ejja ngħidu I enqueue myself, 26?

845
00:36:03,280 --> 00:36:05,890
Inħoss bħal I jappartjenu hawn fuq.

846
00:36:05,890 --> 00:36:06,890
Hekk jien qed enqueued.

847
00:36:06,890 --> 00:36:08,760
So I tip ta jappartjenu hawn.

848
00:36:08,760 --> 00:36:11,300
U anki jekk inti ma pjuttost
japprezzaw dan viżwalment fuq il-palk,

849
00:36:11,300 --> 00:36:15,075
għaliex għandna ħafna spazju, I għandhom
ma tkun wieqfa hawn, għaliex?

850
00:36:15,075 --> 00:36:16,290
>> UDJENZA: Inti barra mill-limiti.

851
00:36:16,290 --> 00:36:16,370
>> DAVID Malan: Dritt.

852
00:36:16,370 --> 00:36:16,940
Jien minn limiti.

853
00:36:16,940 --> 00:36:19,330
Stajt indiċjati lil hinn mill-
limiti ta 'din array.

854
00:36:19,330 --> 00:36:23,420
I really għandhom ikunu f'wieħed mill-
tliet postijiet possibbli.

855
00:36:23,420 --> 00:36:25,150
Issa, fejn l-aktar naturali biex tmur?

856
00:36:25,150 --> 00:36:27,760
Nipproponi aħna leveraged
ġimgħa trick waħda.

857
00:36:27,760 --> 00:36:30,150
L-operatur mod, persentaġġ.

858
00:36:30,150 --> 00:36:36,850
Għaliex jien teknikament wieqfa fil
post 3, iżda I do kapaċità mod 3,

859
00:36:36,850 --> 00:36:40,250
hekk 3, sinjal fil-mija, 3 -

860
00:36:40,250 --> 00:36:40,970
kapaċità għamilhom 3.

861
00:36:40,970 --> 00:36:41,720
X'hemm li?

862
00:36:41,720 --> 00:36:43,700
X'hemm l-bqija meta
inti jaqsam 3 minn 3?

863
00:36:43,700 --> 00:36:44,070
0.

864
00:36:44,070 --> 00:36:48,140
>> Allura li tpoġġi me Jake kienu kienet,
li huwa attwalment tajba.

865
00:36:48,140 --> 00:36:50,370
Allura issa l-implimentazzjoni
ta 'dan il-ħaġa li għaddej biex

866
00:36:50,370 --> 00:36:51,250
tkun daqsxejn ta 'ras.

867
00:36:51,250 --> 00:36:53,740
Huwa tassew biss linja waħda
uġigħ ta 'ras, tal-kodiċi.

868
00:36:53,740 --> 00:36:56,580
Imma l-anqas issa hemm żibel
valur hawn, iżda hemm żewġ

869
00:36:56,580 --> 00:36:57,910
ints leġittimi hawn.

870
00:36:57,910 --> 00:37:04,160
U jien jsostnu li issa għamilna
eżattament dak li għandna bżonn biex jagħmlu dan sakemm

871
00:37:04,160 --> 00:37:08,600
nagħmlu l-bidla dak tal Jake
valur kellha tkun 26.

872
00:37:08,600 --> 00:37:12,110
>> Issa għandna biżżejjed tagħrif li għadu
biex tinżamm l-integrità

873
00:37:12,110 --> 00:37:13,060
ta 'din l-istruttura tad-data.

874
00:37:13,060 --> 00:37:17,160
Aħna qed għadhom tip ta 'minn xortih meta aħna
tixtieq li daħħal erba 'jew aktar total

875
00:37:17,160 --> 00:37:20,740
elementi, iżda nista 'mill-anqas tagħmel pretty
użu effiċjenti ta 'din il-kostanti

876
00:37:20,740 --> 00:37:21,740
żmien, fil-fatt.

877
00:37:21,740 --> 00:37:27,150
I ma jkollhomx għalfejn tinkwieta dwar ċaqliq
kulħadd, kif inklinazzjoni David kien.

878
00:37:27,150 --> 00:37:30,816
>> Kwalunkwe mistoqsijiet dwar stacks,
jew dan kju?

879
00:37:30,816 --> 00:37:32,184
>> UDJENZA: Huwa r-raġuni għaliex
għandek bżonn daqs sabiex inti tkun taf

880
00:37:32,184 --> 00:37:34,010
fejn jkollha persuna?

881
00:37:34,010 --> 00:37:34,770
>> DAVID Malan: Eżattament.

882
00:37:34,770 --> 00:37:38,230
I bżonn ikunu jafu l-daqs tal-array
minħabba I bżonn tkun taf eżattament kif

883
00:37:38,230 --> 00:37:41,940
ħafna minn dawn il-valuri huma leġittimi,
u hekk li nista 'nsib fejn jitqiegħdu

884
00:37:41,940 --> 00:37:42,800
il-persuna li jmiss.

885
00:37:42,800 --> 00:37:43,300
Eżattament.

886
00:37:43,300 --> 00:37:44,580
Id-daqs huwa -

887
00:37:44,580 --> 00:37:46,360
attwalment, aħna ma jaġġornaw din s'issa.

888
00:37:46,360 --> 00:37:48,380
I miżjuda myself fuq 26.

889
00:37:48,380 --> 00:37:51,760
Id-daqs huwa issa, mhux 1, iżda 2.

890
00:37:51,760 --> 00:37:57,780
Allura issa dan tabilħaqq jgħin lili isibu l-
kap tal-lista, li mhix 0, mhux

891
00:37:57,780 --> 00:37:59,250
1, iżda huwa 2.

892
00:37:59,250 --> 00:38:01,665
Il-faċċata tal-lista
huwa tabilħaqq numru 22.

893
00:38:01,665 --> 00:38:05,120
Minħabba li huwa daħal fl-ewwel, hekk hu għandu
jitħallew fil-maħżen qabel me,

894
00:38:05,120 --> 00:38:08,780
anki jekk viżwalment jien wieqfa
eqreb lejn il-maħżen.

895
00:38:08,780 --> 00:38:09,220
>> Kull dritt?

896
00:38:09,220 --> 00:38:12,410
A rawnd ta 'applause għal dawn guys
u aħna ser ħallihom minn hemmhekk.

897
00:38:12,410 --> 00:38:17,090
>> [Applause]

898
00:38:17,090 --> 00:38:18,150
>> DAVID Malan: I tista let
inti żżomm il-trej.

899
00:38:18,150 --> 00:38:20,760
Nistgħu naraw x'jiġri jekk
trid, imma forsi le.

900
00:38:20,760 --> 00:38:21,590
Kull dritt.

901
00:38:21,590 --> 00:38:25,380
Allura dak li issa ma dan il-leave us?

902
00:38:25,380 --> 00:38:28,900
Well, let me tipproponi li hemm
ftit strutturi oħra ta 'data nistgħu

903
00:38:28,900 --> 00:38:33,810
tibda żżid li kit għodda tagħna li se
attwalment jiġi pjuttost, pjuttost rilevanti kif

904
00:38:33,810 --> 00:38:35,270
aħna adsa fis Jittieħed web.

905
00:38:35,270 --> 00:38:38,150
Li għal darb'oħra, għandu xi tip ta 'konnessjoni
siġar fil-forma ta '

906
00:38:38,150 --> 00:38:40,550
xi ħaġa imsejħa DOM, dokument
mudell oġġett.

907
00:38:40,550 --> 00:38:42,370
Iżda aħna ser tara aktar ta '
li qabel twil.

908
00:38:42,370 --> 00:38:46,260
>> Let me tipproponi definitionally li aħna
sejħa siġra issa dak li inti tista 'taf kif

909
00:38:46,260 --> 00:38:48,820
aktar ta 'siġra tal-familja, fejn inti
jkollhom xi antenat fil-

910
00:38:48,820 --> 00:38:49,790
għeruq tas-siġra.

911
00:38:49,790 --> 00:38:54,480
A matriarch patrijarkali jew fi
nett ta 'l-siġra.

912
00:38:54,480 --> 00:38:56,700
Mingħajr konjuġi tagħhom, f'dan il-każ.

913
00:38:56,700 --> 00:39:00,940
Imma issa għandna dak li aħna ser sejħa
tfal, li huma lymph li hang

914
00:39:00,940 --> 00:39:05,480
off-tfal tax-xellug jew il-wild dritt,
vleġeġ kif muri hawn.

915
00:39:05,480 --> 00:39:10,490
>> Fi kliem ieħor, fi struttura data siġra
fil-kompjuter, siġra għandha żero

916
00:39:10,490 --> 00:39:11,480
jew aktar nodes.

917
00:39:11,480 --> 00:39:13,500
Jekk ikun node mill-inqas wieħed,
li sejjaħ l-għerq.

918
00:39:13,500 --> 00:39:15,700
Hu l-affarijiet viżwalment li
aħna tiġbed fil-quċċata.

919
00:39:15,700 --> 00:39:20,280
U li node, bħal kull node oħra, tista '
jkollhom żero, wieħed, jew tnejn, jew tlieta,

920
00:39:20,280 --> 00:39:23,600
jew ħafna tfal madankollu l-
struttura tad-data jappoġġja.

921
00:39:23,600 --> 00:39:29,150
F'dan il-każ, l-għerq, il-ħażna tal-
valur wieħed, għandu żewġt itfal, 2 u 3,

922
00:39:29,150 --> 00:39:33,020
hekk aħna ġeneralment sejħa 2-xellug
tfal u 3-tfal dritt.

923
00:39:33,020 --> 00:39:36,940
>> U allura meta aħna tikseb sa 5, 6, u
7, 6 tista 'tissejjaħ il-wild nofs.

924
00:39:36,940 --> 00:39:38,940
Jekk għandek erbat itfal,
jiġrilha konfużjoni.

925
00:39:38,940 --> 00:39:42,260
Allura aħna tieqaf tuża dak it-tip
ta 'shortcut verbalment.

926
00:39:42,260 --> 00:39:44,580
Imma huwa verament ftit siġra tal-familja.

927
00:39:44,580 --> 00:39:48,880
U l-weraq hawn huma l-lymph li
infushom ikollhom l-ebda tfal.

928
00:39:48,880 --> 00:39:52,540
Huma hang off-qiegħ tas-siġra.

929
00:39:52,540 --> 00:39:56,940
>> Allura kif tista 'nimplimentaw siġra li
għandha biss żewġ tfal maximally?

930
00:39:56,940 --> 00:39:58,410
Aħna ser sejħa hija siġra binarju.

931
00:39:58,410 --> 00:40:00,960
Bi darb'oħra jfisser tnejn, f'dan
każ, bħal ma binarja.

932
00:40:00,960 --> 00:40:04,830
U hekk dan jista 'jkollu żero, wieħed,
jew żewġt itfal maximally.

933
00:40:04,830 --> 00:40:08,650
>> I ser nipproponi li nimplimentaw l-node
għal dik l-istruttura ma 'n int,

934
00:40:08,650 --> 00:40:11,910
u allura żewġ pointers, wieħed imsejjaħ
xellug, wieħed imsejjaħ dritt.

935
00:40:11,910 --> 00:40:14,830
Iżda dawn huma biss sbieħ
konvenzjonijiet arbitrarji.

936
00:40:14,830 --> 00:40:18,170
U x'hemm sbieħ issa, speċjalment jekk inti
tip ta 'tħabtu kunċettwalment ma

937
00:40:18,170 --> 00:40:21,300
recursion, jew ħasbu li ma kienx
verament soluzzjoni għal xejn,

938
00:40:21,300 --> 00:40:23,120
speċjalment jekk inti tista '
jispiċċaw tal-memorja.

939
00:40:23,120 --> 00:40:26,600
Issa li aħna qed jitkellem dwar data
istrutturi u algoritmi li jippermettu

940
00:40:26,600 --> 00:40:31,030
ahna travers u timmanipula minnhom,
Jirriżulta li recursion taqa 'lura fil-

941
00:40:31,030 --> 00:40:34,240
ħafna aktar konvinċenti
jekk mhux mod sabiħ.

942
00:40:34,240 --> 00:40:38,670
>> Allura dan nipproponi huwa l-implimentazzjoni
ta 'funzjoni Search.

943
00:40:38,670 --> 00:40:39,870
Minħabba żewġ inputs -

944
00:40:39,870 --> 00:40:41,570
sabiex jaħsbu ta 'dan bħala kaxxa sewda.

945
00:40:41,570 --> 00:40:46,560
Minħabba żewġ inputs, n, int, u
pointer għal siġra, a pointer għal

946
00:40:46,560 --> 00:40:50,020
node, jew verament l-għerq ta 'siġra, I
pretensjoni li din il-funzjoni tista 'ritorn

947
00:40:50,020 --> 00:40:53,530
vera jew falza, li l-valur n
huwa ġewwa ta 'din is-siġra.

948
00:40:53,530 --> 00:40:55,210
>> X'hemm ġewwa ta 'din il-kaxxa sewda?

949
00:40:55,210 --> 00:40:57,440
Ukoll, erba 'fergħat.

950
00:40:57,440 --> 00:40:58,385
L-ewwel biss kontrolli.

951
00:40:58,385 --> 00:41:00,490
Jekk siġra huwa null, biss ritorn foloz.

952
00:41:00,490 --> 00:41:04,580
Jekk hemm l-ebda node, hemm ebda n,
hemm l-ebda numru, biss ritorn foloz.

953
00:41:04,580 --> 00:41:12,330
Jekk għalkemm, n, il-valur li qed tfittex
għal, huwa inqas minn siġra vleġġa n, u

954
00:41:12,330 --> 00:41:15,180
biss li jkun ċar, dak ma jfisser meta
I jiktbu siġra u allura l-vleġġa

955
00:41:15,180 --> 00:41:18,150
notazzjoni, n?

956
00:41:18,150 --> 00:41:18,690
Eżattament.

957
00:41:18,690 --> 00:41:21,970
Dan ifisser li dereference
pointer imsejħa siġra.

958
00:41:21,970 --> 00:41:26,750
Jmorru hemm, u mbagħad jiksbu ġewwa ta 'dan
node u jiksbu qasam tagħha imsejħa n.

959
00:41:26,750 --> 00:41:30,810
U mbagħad iqabbel ir-n attwali li kien
għadda fis Fittex kontriha.

960
00:41:30,810 --> 00:41:35,390
>> Mela jekk n huwa inqas minn, il-valur n
fil-node siġra nnifisha, ukoll,

961
00:41:35,390 --> 00:41:36,720
dak ma jfisser?

962
00:41:36,720 --> 00:41:40,690
Dan ifisser xejn ewwel daqqa t'għajn.

963
00:41:40,690 --> 00:41:40,900
Dritt?

964
00:41:40,900 --> 00:41:45,560
Eżatt bħal meta jkollok firxa ta '
il-valuri, inti tista 'tixtieq tapplika binarju

965
00:41:45,560 --> 00:41:48,290
tfittxija bħala forma ta 'qasma
u conquer.

966
00:41:48,290 --> 00:41:51,790
Imma dak suppożizzjoni ma hemm bżonn li nagħmlu
għal tfittxija binarja li jaħdmu fil-livelli kollha

967
00:41:51,790 --> 00:41:54,510
fil-ktieb tat-telefon u
eżempji preċedenti?

968
00:41:54,510 --> 00:41:55,530
>> Kif jiġu magħżula.

969
00:41:55,530 --> 00:41:59,490
Mela ejja tirfina d-definizzjoni ta 'siġra
hawn mhux biex tkun biss siġra, li jista '

970
00:41:59,490 --> 00:42:00,880
jkollhom kwalunkwe numru ta 'tfal.

971
00:42:00,880 --> 00:42:04,700
Mhux biss siġra binarju, li jista '
għandhom 0, 1, 2 jew maximally.

972
00:42:04,700 --> 00:42:09,700
Iżda bħala siġra tfittxija binarju, jew BST,
li huwa biss mod fancy ta 'tgħid a

973
00:42:09,700 --> 00:42:15,430
siġra binarju tali li kull node tal
tifel xellug, jekk preżenti, huwa

974
00:42:15,430 --> 00:42:16,830
inqas mill-node.

975
00:42:16,830 --> 00:42:20,170
U tat-tfal kull node id-dritt,
jekk preżenti, huwa akbar

976
00:42:20,170 --> 00:42:21,740
mill-node innifsu.

977
00:42:21,740 --> 00:42:25,200
>> Allura fi kliem ieħor, jekk ġejt biex tiġbed
l-out siġra, kollha tal-numri huma

978
00:42:25,200 --> 00:42:30,620
bbilanċjati bir-reqqa bħal dan hekk li jekk
għandek 55 bħala l-għerq, 33 tista 'tmur

979
00:42:30,620 --> 00:42:33,090
għax-xellug tagħha għaliex dan huwa inqas minn 55.

980
00:42:33,090 --> 00:42:36,430
77 tista 'tmur dritt tagħha minħabba
huwa akbar minn 55.

981
00:42:36,430 --> 00:42:40,750
Imma issa avviż, l-istess definizzjoni,
huwa definizzjoni rikursivi verbalment,

982
00:42:40,750 --> 00:42:42,600
għandu japplika għal 33.

983
00:42:42,600 --> 00:42:47,610
Child Left 33 trid tkun inqas minn dan,
u tat-tfal dritt 33, l-44, għandu jkun

984
00:42:47,610 --> 00:42:48,580
akbar minn dan.

985
00:42:48,580 --> 00:42:51,670
>> Allura dan huwa siġra tfittxija binarju, u
Nipproponi, bl-użu ftit tal-

986
00:42:51,670 --> 00:42:53,910
recursion, nistgħu issa jsibu n.

987
00:42:53,910 --> 00:42:59,160
Mela jekk n huwa inqas mill-valur n li l-
node attwali, jien se jmorru

988
00:42:59,160 --> 00:43:04,090
quddiem u Punt, biex ngħidu hekk, u biss
ritorn ikun x'ikun l-tweġiba hija ta '

989
00:43:04,090 --> 00:43:08,470
tiftix għal n fuq il-
Child Left siġar.

990
00:43:08,470 --> 00:43:11,370
Avviż mill-ġdid, din il-funzjoni biss
jistenna stilla node, a

991
00:43:11,370 --> 00:43:12,780
pointer għal node.

992
00:43:12,780 --> 00:43:17,360
Allura żgur I tista 'biss tagħmel siġra
vleġġa xellug, li se jwassal

993
00:43:17,360 --> 00:43:18,400
me node ieħor.

994
00:43:18,400 --> 00:43:19,480
Imma dak hu li node?

995
00:43:19,480 --> 00:43:22,820
>> Ukoll, skond din id-dikjarazzjoni,
xellug huwa biss pointer, hekk li biss

996
00:43:22,820 --> 00:43:27,090
ifisser jien tgħaddi għall-funzjoni ta 'tfittxija
a pointer differenti, jiġifieri

997
00:43:27,090 --> 00:43:30,750
il-wieħed li jirrappreżenta
siġra tifel xellug tiegħi.

998
00:43:30,750 --> 00:43:36,040
Allura f'dan il-każ, il-pointer sa 33, jekk
dan huwa input kampjun tagħna Sadanittant, jekk

999
00:43:36,040 --> 00:43:40,740
n huwa akbar mill-valur n fil-
node attwali fil-siġra, allura jien

1000
00:43:40,740 --> 00:43:43,370
se jmorru quddiem u Punt fl-ieħor
direzzjoni u biss jgħidu, I ma

1001
00:43:43,370 --> 00:43:47,280
tkun taf jekk dan il-valur n huwa fil-siġra,
imma naf jekk huwa, huwa isfel tiegħi

1002
00:43:47,280 --> 00:43:49,090
fergħa dritt, biex ngħidu hekk.

1003
00:43:49,090 --> 00:43:53,120
So let me sejħa recursively tfittxija,
jgħaddu minn n-ġdid, iżda li tgħaddi fil-

1004
00:43:53,120 --> 00:43:54,580
pointer għat-tarbija dritt tiegħi.

1005
00:43:54,580 --> 00:44:00,020
>> Fi kliem ieħor, jekk jien bħalissa 55
u jien infittxu 99, naf li 99

1006
00:44:00,020 --> 00:44:04,270
huwa akbar minn 55, hekk bħad I Tore
il-ġimgħat ktieb tat-telefon ilu u aħna

1007
00:44:04,270 --> 00:44:07,140
marru dritt, bl-istess mod aħna
se jmorru dritt hawn.

1008
00:44:07,140 --> 00:44:11,960
U jien ma nafx jekk huwa fil-lemin tiegħi
tfal, u mhuwiex, 77 hemm, iżda

1009
00:44:11,960 --> 00:44:13,210
Naf huwa f'dik id-direzzjoni.

1010
00:44:13,210 --> 00:44:18,770
So I call tfittxija fuq tifel lemin tiegħi,
77, u ħalli figura tfittxija out minn

1011
00:44:18,770 --> 00:44:24,950
hemm jekk 99 f'dan arbitrarja
Eżempju huwa attwalment hemm.

1012
00:44:24,950 --> 00:44:26,900
>> Else, x'inhu l-każ finali?

1013
00:44:26,900 --> 00:44:28,620
Jekk siġra huwa null każ wieħed.

1014
00:44:28,620 --> 00:44:31,890
Jekk n huwa inqas mill-node tal attwali
valur huwa każ ieħor.

1015
00:44:31,890 --> 00:44:35,120
Jekk n hija akbar mill-kurrenti
valur node huwa terz każ.

1016
00:44:35,120 --> 00:44:38,250
X'hemm-raba 'u laħħar każ?

1017
00:44:38,250 --> 00:44:39,480
I think we qed barra ta 'każijiet, id-dritt?

1018
00:44:39,480 --> 00:44:44,690
Hija għandha tkun li n hija fil-
node attwali li jien fuq.

1019
00:44:44,690 --> 00:44:49,640
>> Mela jekk jien tiftix għal 55 f'dan il-punt
fl-istorja, dik il-fergħa ta 'l-

1020
00:44:49,640 --> 00:44:51,780
siġra se jerġa 'lura veru.

1021
00:44:51,780 --> 00:44:55,380
Allura x'hemm interessanti hawnhekk huwa li aħna
attwalment, b'differenza ġimgħat li għaddew, irridu tip

1022
00:44:55,380 --> 00:44:56,740
ta 'jkollu żewġ każijiet bażi.

1023
00:44:56,740 --> 00:44:58,300
U dawn ma jkollhom
ikunu kollha fil-quċċata.

1024
00:44:58,300 --> 00:45:01,390
Il-quċċata hija każ bażiku għaliex jekk il-
siġra huwa null, hemm xejn li jagħmlu.

1025
00:45:01,390 --> 00:45:03,410
Just jirritornaw hard kodifikata
valur ta 'riżultati foloz.

1026
00:45:03,410 --> 00:45:07,400
>> Il-fergħa tal-qiegħ huwa tip ta 'l-
default, fejn jekk konna ċċekkjati għal

1027
00:45:07,400 --> 00:45:11,550
null, konna ċċekkjati jekk għandu jkun
xellug, iżda ma għandu jkun, konna

1028
00:45:11,550 --> 00:45:14,640
ċċekkjati jekk għandu jkun dritt, iżda
m'għandux ikun, b'mod ċar għandu jkun

1029
00:45:14,640 --> 00:45:15,870
dritt fejn aħna.

1030
00:45:15,870 --> 00:45:16,780
Li l-każ bażi.

1031
00:45:16,780 --> 00:45:19,920
Allura hemm żewġ każijiet rikursivi
mgħaffeġ hemm fin-nofs.

1032
00:45:19,920 --> 00:45:21,630
Imma I setgħet bil-miktub
dan fi kwalunkwe ordni.

1033
00:45:21,630 --> 00:45:24,520
I maħsub biss tip ta 'ħass naturali
li l-ewwel jikkontrolla għal żball possibbli,

1034
00:45:24,520 --> 00:45:28,340
mbagħad tiċċekkja xellug, mbagħad tiċċekkja dritt, imbagħad
jassumi li int fil-node

1035
00:45:28,340 --> 00:45:30,630
int fil-fatt tfittex.

1036
00:45:30,630 --> 00:45:36,240
>> Allura għaliex jista 'dan jiġi utli?

1037
00:45:36,240 --> 00:45:37,910
Għalhekk jirriżulta li -

1038
00:45:37,910 --> 00:45:42,110
u let me jaqbżu teaser
hawn li fil-web.

1039
00:45:42,110 --> 00:45:44,920
Aħna ser tibda tuża mhux
programmazzjoni lingwa fl-ewwel, iżda

1040
00:45:44,920 --> 00:45:46,030
lingwa markup.

1041
00:45:46,030 --> 00:45:48,740
A lingwa markup hija waħda li l-
simili fl-ispirtu l-ipprogrammar

1042
00:45:48,740 --> 00:45:51,715
lingwa, iżda ma jagħtuk l-
ħila biex tesprimi ruħek loġikament.

1043
00:45:51,715 --> 00:45:55,070
Hija biss jagħtik l-abbiltà li
tesprimi lilek innifsek strutturalment.

1044
00:45:55,070 --> 00:45:57,960
>> Meta inti tixtieq li tqiegħed xi ħaġa
fuq il-paġna, il-paġna web?

1045
00:45:57,960 --> 00:45:59,200
Liema kulur inti tixtieq li tagħmel dan?

1046
00:45:59,200 --> 00:46:00,950
Liema daqs tat-tipa inti tixtieq li tagħmel dan?

1047
00:46:00,950 --> 00:46:02,970
Liema kliem do inti fil-fatt
trid fuq il-paġna web?

1048
00:46:02,970 --> 00:46:04,060
Allura dak lingwa markup.

1049
00:46:04,060 --> 00:46:07,690
Imma allura aħna ser jintroduċu malajr ħafna
JavaScript, li hija full-sħiħ

1050
00:46:07,690 --> 00:46:08,560
programmazzjoni lingwa.

1051
00:46:08,560 --> 00:46:12,530
Simili ħafna sintattikament fid-dehra
li C, iżda ser ikollhom xi

1052
00:46:12,530 --> 00:46:15,200
sbieħ, aktar qawwija, aktar
karatteristiċi faċli għall-utent.

1053
00:46:15,200 --> 00:46:18,050
>> U wieħed mill-frustrazzjonijiet f'dan
punt fil-semestru hija li aħna ser

1054
00:46:18,050 --> 00:46:22,065
Hekk jimplimentaw speller fil ferm inqas
linji ta 'kodiċi li jużaw lingwi

1055
00:46:22,065 --> 00:46:25,580
minn C nnifisha tippermetti, iżda għal raġuni ta
aħna ser dalwaqt jifhmu.

1056
00:46:25,580 --> 00:46:27,750
Dan se jkun l-ewwel paġna web tali.

1057
00:46:27,750 --> 00:46:30,120
Din se tkun kompletament underwhelming,
l-ewwel waħda nagħmlu.

1058
00:46:30,120 --> 00:46:31,400
Hija se sempliċement jgħidu, bonjour dinja.

1059
00:46:31,400 --> 00:46:34,010
Imma jekk inti stajt qatt raw dan
qabel, dan huwa HTML,

1060
00:46:34,010 --> 00:46:35,670
HyperText Markup Language.

1061
00:46:35,670 --> 00:46:39,310
>> Jekk inti tmur lil ċerti għażla menu fil
aktar xi browser, fuq kull paġna web fuq

1062
00:46:39,310 --> 00:46:43,160
l-internet, tista 'tara l-HTML
li xi nies kiteb

1063
00:46:43,160 --> 00:46:44,400
joħolqu dik il-paġna web.

1064
00:46:44,400 --> 00:46:47,850
U probabbilment ma tfittex
qosor jew kif pulita bħala dan.

1065
00:46:47,850 --> 00:46:51,400
Iżda se ssegwi l-mudell ta 'dawn
parentesi miftuħa u slashes u

1066
00:46:51,400 --> 00:46:53,660
ittri u n-numri potenzjalment.

1067
00:46:53,660 --> 00:46:56,770
>> Ħsibt I d jagħtik teaser
ta 'dak li inti ser tkun tista' tagħmel

1068
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wara li tieħu CS50.

1069
00:46:57,950 --> 00:47:02,620
Let me mur cs.harvard.edu / Rob,
homepage tagħna stess Bowden Rob tal.

1070
00:47:02,620 --> 00:47:06,080
Huwa għamel dan għalina.

1071
00:47:06,080 --> 00:47:07,490
Allura inti ser dalwaqt tkun kapaċi li jagħmlu dan.

1072
00:47:07,490 --> 00:47:10,660
U wkoll, dak li inti smajt
dalgħodu -

1073
00:47:10,660 --> 00:47:12,480
dak li inti smajt dalgħodu -

1074
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>> [Ħamster DANCE MUSIC]

1075
00:47:13,780 --> 00:47:15,702
>> - You'll ikunu jistgħu jagħmlu dan.

1076
00:47:15,702 --> 00:47:16,790
Li jistenna minna nhar l-Erbgħa.

1077
00:47:16,790 --> 00:47:17,791
Aħna se tara inti mbagħad.

1078
00:47:17,791 --> 00:47:22,950
>> [Ħamster DANCE MUSIC]

1079
00:47:22,950 --> 00:47:24,300
DAVID Malan: Fl-CS50 jmiss -

1080
00:47:24,300 --> 00:47:31,670