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[Daqq ta mużika]

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SPEAKER 1: Kull dritt.

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Kulħadd merħba lura għat-taqsima.

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Nispera li intom kollha huma b'suċċess
rkuprati minn kwizz tiegħek

7
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mill-aħħar ġimgħa.

8
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Naf huwa ftit crazy f'ħinijiet.

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Kif I kien qal qabel, jekk int
fi ħdan id-devjazzjoni standard,

10
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ma verament tinkwieta dwar dan, speċjalment
għal taqsima inqas komdi.

11
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Dan huwa madwar fejn inti għandek tkun.

12
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>> Jekk inti għamilt kbir, imbagħad biża.

13
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Kudos lilek.

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U jekk inti tħoss bħal għandek bżonn
ftit aktar għajnuna, jekk jogħġbok

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tħossok liberu li jilħqu
out għal xi TFS.

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Aħna lkoll hawn biex jgħinu.

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>> C'est pourquoi aħna jgħallmu.

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C'est pourquoi jien hawn kull Tnejn għalik
guys u fl-uffiċċju sigħat nhar ta 'Ħamis.

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Allura jekk jogħġbok tħossok liberu li let me know
jekk int inkwetat dwar xi ħaġa

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jew jekk hemm xi ħaġa fuq l-kwizz
li youd verament tixtieq tindirizza.

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>> Għalhekk l-aġenda għal-lum huwa
kollha dwar strutturi ta 'dejta.

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Uħud minn dawn huma biss ser tkun biss
biex inti tikseb familiarized ma 'dawn.

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Inti tista 'ma qatt jimplimentaw
minnhom f'din il-klassi.

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Xi wħud minnhom inti se,
bħal per pset speller tiegħek.

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>> Inti ser ikollok l-għażla tiegħek
bejn tabelli hash u tipprova.

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Allura aħna ser definittivament jkunu għaddejjin fuq dawk.

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Li għaddej biex tkun definittivament aktar ta 'tip
ta 'sezzjoni livellata għoli llum, għalkemm,

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minħabba li hemm ħafna minnhom, u jekk
aħna marru fis-dettalji ta 'implimentazzjoni

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fuq kollha ta 'dawn, aħna se le
anki nikseb permezz ta 'listi marbuta

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u forsi xi ftit ta 'tabelli hash.

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>> Allura jkollhom miegħi.

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Aħna mhux se tkun qed twettaq
daqshekk kodifikazzjoni dan iż-żmien.

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Jekk għandek xi mistoqsijiet dwar dan
jew inti tixtieq li tara implimentata

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jew jippruvaw hija għalik innifsek,
I definitely jirrakkomandaw

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ser study.cs50.net, li
għandha eżempji ta 'dawn kollha.

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Hija ser ikollhom powerpoints tiegħi
man-noti li aħna

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għandhom tendenza li jużaw kif ukoll xi programmazzjoni
eżerċizzji, speċjalment għall-affarijiet

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bħal listi konnessi u binarja
stacks siġar u cues.

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Allura ftit aktar livell għoli, li
jista 'jkun sbieħ għall inti guys.

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>> Allura ma 'dan, aħna ser tibda.

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U wkoll, kwizzijiet yes--.

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Naħseb li ħafna minnkom li huma fil-
taqsima tiegħi jkollhom kwizzijiet tiegħek,

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iżda xi ħadd jiġi fl jew xi raġuni inti
ma, dawn qed dritt hawn fl-quddiem.

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>> Hekk listi marbuta.

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Naf li dan it-tip ta 'tmur
li back qabel kwizz tiegħek.

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Dan kien l-ġimgħa qabel
li aħna tgħallmu dwar dan.

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Iżda f'dan il-każ, aħna ser biss
jmorru ftit aktar fil-fond.

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>> Allura għaliex jista nagħżlu
marbut lista fuq firxa?

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Dak li jiddistingwihom minnhom?

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Iva?

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>> UDJENZA: Inti tista 'tespandi a marbut
lista versus daqs fiss ta 'firxa.

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SPEAKER 1: Dritt.

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Firxa ffissat daqs billi
lista marbuta għandu daqs varjabbli.

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Hekk jekk ma nafux kif
kemm aħna tixtieq li taħżen,

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lista marbuta jagħtina kbir
mod biex tagħmel dan għaliex nistgħu biss

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żid fuq node ieħor u żid fuq
node u ieħor żid fuq node ieħor.

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Imma dak li jista 'jkun kompromess?

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Ħadd ma tiftakar il-kompromess
bejn arrays u listi marbuta?

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Mmhmm?

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>> UDJENZA: Inti għandek biex
jgħaddu-triq kollha

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permezz tal-lista marbuta
isibu element f'lista.

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Fil-firxa, inti tista
biss issib element.

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>> SPEAKER 1: Dritt.

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Allura ma arrays--

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>> UDJENZA: [inaudible].

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>> SPEAKER 1: Bil arrays, għandna
dak li sejjaħ aċċess bl-addoċċ.

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Ifisser li jekk irridu dak li huwa
qatt il-ħames punt ta 'lista

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jew il-ħames punt ta 'tagħna
firxa, nistgħu biss grab dan.

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Jekk huwa lista marbuta, għandna
li jtenni permezz, id-dritt?

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Allura aċċess element fil
firxa huwa żmien kostanti,

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billi ma 'lista marbuta li kieku
jkun x'aktarx ħin lineari għaliex forsi

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element tagħna huwa l-triq kollha fl-aħħar.

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Irridu tfittxija permezz kollox.

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Allura ma 'dawn id-data kollha
istrutturi aħna qed tmur

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li tkun infiq ftit aktar ħin fuq,
liema huma l-pluses u negattivi.

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Meta tista irridu
tuża wieħed fuq l-ieħor?

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U dak l-tip ta 'l-
ħaġa akbar għal take away.

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>> Allura għandna hawnhekk l-
definizzjoni ta 'node.

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Huwa simili element wieħed fl
lista marbuta tagħna, id-dritt?

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Allura aħna qed kollha familjari
mal structs typedef tagħna,

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li aħna marru fuq fl-analiżi aħħar darba.

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Kien bażikament biss joħolqu
tip ieħor data li nistgħu jużaw.

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>> U f'dan il-każ, huwa xi node
li ser ikollu xi numru sħiħ fil.

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U allura x'inhu l-tieni parti hawn?

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Xi ħadd?

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>> UDJENZA: [inaudible].

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>> SPEAKER 1: Yeah.

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Huwa pointer għall-node li jmiss.

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Allura dan għandu attwalment ikun up here.

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Din hija pointer tat-tip
node għall-ħaġa li jmiss.

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U dan huwa dak li
jinkludi node tagħna.

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Kessaħ.

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>> Kull dritt, hekk bil-tfittxija, kif konna
biss qal qabel l-idejn, jekk int

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ser tfittex permezz,
inti għandek attwalment jtenni

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permezz lista marbuta tiegħek.

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Hekk jekk aħna qed tfittex għan-numru
9, aħna se tibda fil-kap tagħna

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u li l-punti magħna fil-bidu
tal-lista marbuta tagħna, id-dritt?

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U aħna ngħidu, OK, ma dan
node fih in-numru 9?

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No?

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>> Kull dritt, mur l-wieħed li jmiss.

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Segwi dan.

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Ma fiha n-numru 9?

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No

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Segwi l-wieħed li jmiss.

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>> Allura aħna għandna biex effettivament jtenni
permezz lista marbuta tagħna.

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Ma nistgħux sempliċement tmur direttament lejn fejn 9 hu.

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U jekk inti guys fil-fatt tixtieq li
tara xi psewdo-kodiċi up hemm.

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Għandna xi funzjoni ta 'tfittxija hawn
li jieħu in-- dak li ma jieħdu fil-?

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00:05:10,420 --> 00:05:13,110

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What do you think?

112
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Wieħed daqshekk faċli.

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X'inhu dan?

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UDJENZA: [inaudible].

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SPEAKER 1: L-għadd aħna qed tfittex.

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Dritt?

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U dak li dan jikkorrispondi għall?

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Huwa pointer li?

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>> UDJENZA: A node.

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>> SPEAKER 1: A node għal-lista
li aħna qed tħares lejn, id-dritt?

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Allura aħna għandna xi glandoli huma pointer hawn.

122
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Dan huwa punt li għaddej biex
attwalment jtenni permezz lista tagħna.

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Waqqafna din ugwali għall-lista
għaliex dan huwa biss

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dan ikun iffissat ugwali għall-
bidu tal-lista marbuta tagħna.

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>> U filwaqt li huwa ma NULL, filwaqt li
aħna xorta jkollhom affarijiet fil-lista tagħna,

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tikkontrolla biex tara jekk dik node għandha
in-numru aħna qed tfittex.

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Ritorn vera.

128
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Inkella, jaġġornah, id-dritt?

129
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>> Jekk huwa NULL, aħna ħruġ tagħna
filwaqt loop u r-ritorn foloz

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għaliex dan ifisser li aħna ma sabu dan.

131
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Does kulħadd nikseb kif din taħdem?

132
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OK.

133
00:06:11,548 --> 00:06:14,940

134
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>> Allura ma inserzjoni, inti
għandhom tliet modi differenti.

135
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Tista prepend, inti tista 'tehmeż
u inti tista 'daħħal fis assortiti.

136
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F'dan il-każ, aħna qed
se tagħmel prepend.

137
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Ħadd ma jaf kif dawk
tliet każijiet jistgħu jvarjaw?

138
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>> Allura prepend ifisser li inti tpoġġi
huwa fuq quddiem tal-lista tiegħek.

139
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Allura dan ikun ifisser li l-ebda kwistjoni
dak node tiegħek huwa, irrelevanti

140
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dak il-valur huwa, int ser
li tqiegħed lilha dritt hawn fuq quddiem, OK?

141
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Li għaddej biex tkun l-ewwel
element fil-lista tiegħek.

142
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>> Jekk inti tehmeż dan, li għaddej
biex tmur fil-dahar tal-lista tiegħek.

143
00:06:49,510 --> 00:06:54,010
U daħħal fis assortiti ifisser li int
ser jitqiegħdu fil-fatt fil-post

144
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fejn iżomm lista marbuta tiegħek magħżula.

145
00:06:57,700 --> 00:07:00,810
Għal darb'oħra, kif tuża
dawn u meta tuża

146
00:07:00,810 --> 00:07:02,530
minnhom se jvarjaw skond il-każ tiegħek.

147
00:07:02,530 --> 00:07:05,834

148
00:07:05,834 --> 00:07:07,750
Jekk ma bżonn
jiġu magħżula, prepend tendenza

149
00:07:07,750 --> 00:07:10,460
li jkun dak li ħafna nies
jużaw għaliex inti ma

150
00:07:10,460 --> 00:07:15,680
għandhom jgħaddu l-lista sħiħa
biex isibu l-aħħar iżżidhiex fuq, id-dritt?

151
00:07:15,680 --> 00:07:17,720
Inti tista 'biss stick dan id-dritt fil-.

152
00:07:17,720 --> 00:07:21,930
>> Allura aħna se jmorru permezz ta '
inserzjoni 1 id-dritt issa.

153
00:07:21,930 --> 00:07:26,360
Ħaġa Allura wieħed li jien ser
jirrakkomanda ħafna fuq dan pset

154
00:07:26,360 --> 00:07:29,820
huwa li tiġbed l-affarijiet out, bħal dejjem.

155
00:07:29,820 --> 00:07:35,130
Huwa importanti ħafna li inti aġġornament
pointers tiegħek fl-ordni korretta

156
00:07:35,130 --> 00:07:38,620
għaliex jekk inti taġġornahom
ftit out of order,

157
00:07:38,620 --> 00:07:42,210
int ser jispiċċaw
jitilfu partijiet tal-lista tiegħek.

158
00:07:42,210 --> 00:07:49,680
>> Hekk per eżempju, f'dan il-każ, aħna qed
javżak-ras għal ftit punt 1.

159
00:07:49,680 --> 00:07:56,070
Jekk aħna biss tagħmel dan
mingħajr iffrankar dan 1,

160
00:07:56,070 --> 00:07:58,570
aħna għandna ebda idea dak li
1 għandu jindika li issa

161
00:07:58,570 --> 00:08:02,490
għaliex aħna tilfu dak
il-kap indikat.

162
00:08:02,490 --> 00:08:05,530
Allura ħaġa waħda li tiftakar
meta int tagħmel prepend

163
00:08:05,530 --> 00:08:09,630
hu li jsalva dak li l-
punti Head sa l-ewwel,

164
00:08:09,630 --> 00:08:15,210
imbagħad jassenja mill-ġdid, u mbagħad taġġorna
dak node ġdid tiegħek għandu jindika.

165
00:08:15,210 --> 00:08:20,870

166
00:08:20,870 --> 00:08:22,560
F'dan il-każ, dan huwa mod wieħed biex tagħmel dan.

167
00:08:22,560 --> 00:08:25,440
>> Hekk jekk aħna kienu għamlu dan il-mod
fejn aħna biss assenjati mill-ġdid tar-ras,

168
00:08:25,440 --> 00:08:30,320
aħna jitilfu bażikament tagħna
lista sħiħa, id-dritt?

169
00:08:30,320 --> 00:08:38,000
Mod wieħed biex tagħmel dan huwa li jkollhom 1 punt li
jmiss, u mbagħad ikollhom punt ras għal 1.

170
00:08:38,000 --> 00:08:42,650
Jew inti tista 'tagħmel it-tip ta bħall-
ħażna temporanja, li jiena tkellem dwar.

171
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>> Iżda jassenjaw mill-ġdid tiegħek
pointers fl-ordni korretta

172
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se tkun ħafna, ħafna
importanti għal din pset.

173
00:08:48,750 --> 00:08:53,140
Inkella, int se jkollhom hash
mejda jew jipprova li jinsab biss se tkun

174
00:08:53,140 --> 00:08:56,014
parti biss tal-kliem li inti
tixtieq u mbagħad mmhmm you're--?

175
00:08:56,014 --> 00:08:58,930
UDJENZA: Liema kienet l-temporanja
Ħaġa ħażna inti kienu jitkellem dwar?

176
00:08:58,930 --> 00:09:00,305
SPEAKER 1: Il-ħażna temporanja.

177
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Allura bażikament ieħor
mod inti tista 'tagħmel dan

178
00:09:02,760 --> 00:09:07,650
huwa jaħżen il-kap ta 'xi ħaġa, bħal
jaħżnuh il-varjabbli temporanju.

179
00:09:07,650 --> 00:09:11,250
Tassenja din għal 1 u
imbagħad jaġġornaw 1 punt

180
00:09:11,250 --> 00:09:13,830
għal dak kollu ras użati għall-punt li.

181
00:09:13,830 --> 00:09:16,920
Dan il-mod huwa ovvjament
aktar eleganti għaliex inti

182
00:09:16,920 --> 00:09:20,770
m'għandhomx bżonn valur temporanju, iżda
ftit joffru mod ieħor biex tagħmel dan.

183
00:09:20,770 --> 00:09:23,999

184
00:09:23,999 --> 00:09:25,790
U għandna attwalment do jkollhom
xi kodiċi għal dan.

185
00:09:25,790 --> 00:09:28,080
Allura għal-lista marbuta, aħna
attwalment ikollhom xi kodiċi.

186
00:09:28,080 --> 00:09:31,930
Allura daħħal hawn, dan huwa prepending.

187
00:09:31,930 --> 00:09:34,290
Allura dan jidħol dan fil-ras.

188
00:09:34,290 --> 00:09:38,820
>> Allura l-ewwel ħaġa, għandek bżonn li
joħolqu node ġdid tiegħek, naturalment,

189
00:09:38,820 --> 00:09:40,790
u ċċekkja għall NULL.

190
00:09:40,790 --> 00:09:43,250
Dejjem tajjeb.

191
00:09:43,250 --> 00:09:47,840
U allura inti għandek bżonn biex tassenja l-valuri.

192
00:09:47,840 --> 00:09:51,260
Kull meta inti toħloq node ġdid, inti
ma jafux liema huwa tipponta lejn jmiss,

193
00:09:51,260 --> 00:09:54,560
sabiex inti tixtieq li initialize li NULL.

194
00:09:54,560 --> 00:09:58,760
Jekk ma jispiċċaw tipponta lejn xi ħaġa
inkella, jiġrilha riassenjata u huwa multa.

195
00:09:58,760 --> 00:10:00,740
Jekk huwa l-ewwel ħaġa
fil-lista, jeħtieġ

196
00:10:00,740 --> 00:10:04,270
għall-punt li NULL għaliex
dak l-aħħar tal-lista.

197
00:10:04,270 --> 00:10:12,410
>> Hekk allura li daħħalha, naraw hawnhekk aħna
jassenjaw il-valur li jmiss ta 'node tagħna

198
00:10:12,410 --> 00:10:17,380
li jkun x'ikun ras hija,
li huwa dak li kellna hawn.

199
00:10:17,380 --> 00:10:19,930
Dak hu li aħna biss għamlet.

200
00:10:19,930 --> 00:10:25,820
U allura aħna qed jassenjaw ras il-punt
biex node ġdid tagħna, għaliex ftakar,

201
00:10:25,820 --> 00:10:31,090
ġdid hija xi pointer għal node,
u dan huwa eżattament dak li ras hija.

202
00:10:31,090 --> 00:10:34,370
Dan huwa eżattament għaliex aħna
jkollhom din vleġġa accessor.

203
00:10:34,370 --> 00:10:37,030

204
00:10:37,030 --> 00:10:37,530
Kessaħ?

205
00:10:37,530 --> 00:10:38,130
Mmhmm?

206
00:10:38,130 --> 00:10:41,100
>> UDJENZA: Do irridu
initialize jmiss ġdid għall NULL ewwel,

207
00:10:41,100 --> 00:10:44,240
jew nistgħu sempliċement initialize dan li ras?

208
00:10:44,240 --> 00:10:48,210
>> SPEAKER 1: li jmiss New
jeħtieġ li jkun NULL biex tibda

209
00:10:48,210 --> 00:10:53,760
għaliex inti ma tafx
fejn huwa għaddej biex tkun.

210
00:10:53,760 --> 00:10:56,100
Ukoll, dan huwa tip ta '
bħad paradigma.

211
00:10:56,100 --> 00:10:59,900
Int tkun qed tissettja ugwali għal NULL biss li tagħmel
żgur li bażijiet kollha tiegħek huma koperti

212
00:10:59,900 --> 00:11:04,070
qabel ma tagħmel xi assenjar sabiex
int dejjem garantit li se

213
00:11:04,070 --> 00:11:08,880
tkun tipponta lejn valur speċifiku
versus bħal valur żibel.

214
00:11:08,880 --> 00:11:12,210
Minħabba, yeah, aħna tassenja
awtomatikament ġdid li jmiss,

215
00:11:12,210 --> 00:11:15,420
iżda huwa aktar biss bħal
prattika tajba li initialize dan

216
00:11:15,420 --> 00:11:19,270
b'dak il-mod u mbagħad jassenja mill-ġdid.

217
00:11:19,270 --> 00:11:23,420
>> OK, listi marbuta hekk doppjament issa.

218
00:11:23,420 --> 00:11:24,601
What do naħsbu?

219
00:11:24,601 --> 00:11:26,350
X'hemm differenti ma
listi marbuta doppjament?

220
00:11:26,350 --> 00:11:30,750

221
00:11:30,750 --> 00:11:34,300
>> Allura fil-listi marbuta tagħna, nistgħu
biss jimxu f'direzzjoni waħda, id-dritt?

222
00:11:34,300 --> 00:11:35,270
Aħna biss li jmiss.

223
00:11:35,270 --> 00:11:36,760
Nistgħu biss jimxu 'l quddiem.

224
00:11:36,760 --> 00:11:40,300
>> Ma 'lista marbuta doppjament,
nistgħu wkoll jimxu lura.

225
00:11:40,300 --> 00:11:44,810
Allura aħna għandna mhux biss il-
Numru li aħna tixtieq li taħżen,

226
00:11:44,810 --> 00:11:50,110
għandna fejn hija tirreferi għall jmiss
u fejn aħna biss ġew minn.

227
00:11:50,110 --> 00:11:52,865
Allura dan jippermetti
xi traversal aħjar.

228
00:11:52,865 --> 00:11:56,620

229
00:11:56,620 --> 00:12:01,240
>> Lymph hekk doppjament marbuta,
simili ħafna, id-dritt?

230
00:12:01,240 --> 00:12:05,000
Differenza Biss issa hija aħna
ikollhom jmiss u preċedenti.

231
00:12:05,000 --> 00:12:06,235
Hu l-unika differenza.

232
00:12:06,235 --> 00:12:09,570

233
00:12:09,570 --> 00:12:14,790
>> Hekk jekk konna biex prepend jew append-- aħna
ma jkollhom ebda kodiċi għall dan up here--

234
00:12:14,790 --> 00:12:17,830
imma jekk ġejt biex jippruvaw u
daħħalha, il-ħaġa importanti

235
00:12:17,830 --> 00:12:19,980
huwa inti bżonn tagħmel
żgur li int qed assenjazzjoni

236
00:12:19,980 --> 00:12:23,360
kemm preċedenti tiegħek u tiegħek
pointer jmiss korrett.

237
00:12:23,360 --> 00:12:29,010
Allura f'dan il-każ, inti
mhux biss initialize jmiss,

238
00:12:29,010 --> 00:12:31,820
inti initialize preċedenti.

239
00:12:31,820 --> 00:12:36,960
Jekk aħna qed fil-kap tal-lista, aħna
mhux biss tagħmel ras ugwali ġdid,

240
00:12:36,960 --> 00:12:41,750
iżda għandha preċedenti ġdida tagħna
punt għall-ras, id-dritt?

241
00:12:41,750 --> 00:12:43,380
>> Dik hija l-unika differenza.

242
00:12:43,380 --> 00:12:47,200
U jekk inti tixtieq aktar prattika ma
dawn ma 'listi marbuta, bil ddaħħal,

243
00:12:47,200 --> 00:12:49,900
ma tħassar, ma daħħal
fis lista assortiti,

244
00:12:49,900 --> 00:12:52,670
jekk jogħġbok iċċekkja study.cs50.net.

245
00:12:52,670 --> 00:12:54,870
Hemm mazz ta 'eżerċizzji kbira.

246
00:12:54,870 --> 00:12:55,870
I jirrakkomanda ħafna minnhom.

247
00:12:55,870 --> 00:12:59,210
Nixtieq kellna ħin biex tmur permezz tagħhom
imma hemm ħafna ta 'strutturi ta' dejta

248
00:12:59,210 --> 00:13:01,530
li tinkiseb permezz.

249
00:13:01,530 --> 00:13:02,650
>> OK, hekk tabelli hash.

250
00:13:02,650 --> 00:13:07,070
Din hija probabbilment l-aktar
bit utli għall pset tiegħek

251
00:13:07,070 --> 00:13:11,090
hawnhekk għaliex int ser tkun
implimentazzjoni waħda minn dawn, jew jipprova.

252
00:13:11,090 --> 00:13:12,200
I really simili tabelli hash.

253
00:13:12,200 --> 00:13:13,110
Huma qed pretty jibred.

254
00:13:13,110 --> 00:13:17,080
>> Allura bażikament dak
jiġri huwa tabella hash

255
00:13:17,080 --> 00:13:22,050
huwa meta aħna verament bżonn ta 'malajr
inserzjoni, tħassir, u Lookup.

256
00:13:22,050 --> 00:13:25,010
Dawk huma l-affarijiet li aħna qed
prijoritizzazzjoni f'tabella hash.

257
00:13:25,010 --> 00:13:29,500
Huma jistgħu jiksbu pretty big,
imma kif aħna ser tara mal tentattivi,

258
00:13:29,500 --> 00:13:33,040
hemm affarijiet li huma ħafna akbar.

259
00:13:33,040 --> 00:13:38,330
>> Imma bażikament, kollha hash
tabella hija funzjoni hash

260
00:13:38,330 --> 00:13:47,215
li jgħidlek liema barmil tpoġġi kull
tad-data tiegħek, kull wieħed mill-elementi tiegħek fil.

261
00:13:47,215 --> 00:13:51,140
A mod sempliċi biex jaħsbu ta 'tabella hash
hija li huwa biss bramel ta 'affarijiet,

262
00:13:51,140 --> 00:13:51,770
dritt?

263
00:13:51,770 --> 00:13:59,720
Allura meta inti qed issortjar affarijiet minn
bħall-ewwel ittra ta 'isem tagħhom,

264
00:13:59,720 --> 00:14:01,820
thats tip simili ta 'tabella hash.

265
00:14:01,820 --> 00:14:06,180
>> Mela jekk jien kienu li grupp inti guys huwa
fi gruppi ta 'min jibda l-isem tal-

266
00:14:06,180 --> 00:14:11,670
mal A hawn fuq, jew min birthday
hija f'Jannar, Frar, Marzu,

267
00:14:11,670 --> 00:14:15,220
tkun xi tkun, li tkun effettivament
ħolqien ta 'tabella hash.

268
00:14:15,220 --> 00:14:18,120
Huwa biss joħolqu bramel li
inti sort elementi tiegħek fis

269
00:14:18,120 --> 00:14:19,520
sabiex inti tista 'issibhom aktar faċli.

270
00:14:19,520 --> 00:14:22,300
Allura dan il-mod meta I ħtieġa
biex isibu waħda minnkom,

271
00:14:22,300 --> 00:14:24,680
I ma jkollhomx biex tfittex
permezz ta 'kull ta' ismijiet tiegħek.

272
00:14:24,680 --> 00:14:29,490
I jistgħu jkunu simili, oh, naf li
Birthday Danielle hija in--

273
00:14:29,490 --> 00:14:30,240
UDJENZA: --April.

274
00:14:30,240 --> 00:14:30,948
SPEAKER 1: April.

275
00:14:30,948 --> 00:14:33,120
So I ħarsa f'April tiegħi
barmil, u ma 'kwalunkwe Xorti,

276
00:14:33,120 --> 00:14:38,270
hi ser tkun l-unika waħda fil hemm u
ħin tiegħi kien kostanti f'dan is-sens,

277
00:14:38,270 --> 00:14:41,230
billi jekk I jkollha tħares
permezz mazz sħiħ ta 'persuni,

278
00:14:41,230 --> 00:14:43,090
li għaddej biex jieħu ħafna aktar.

279
00:14:43,090 --> 00:14:45,830
Allura tabelli hash huma verament biss bramel.

280
00:14:45,830 --> 00:14:48,630
Mod faċli biex jaħsbu minnhom.

281
00:14:48,630 --> 00:14:52,930
>> Allura ħaġa importanti ħafna dwar
tabella hash hija funzjoni hash.

282
00:14:52,930 --> 00:14:58,140
Allura l-affarijiet I biss tkellmu dwar, bħal
ewwel ittra tiegħek ta 'l-ewwel isem tiegħek

283
00:14:58,140 --> 00:15:01,450
jew xahar birthday tiegħek,
dawn huma ideat li

284
00:15:01,450 --> 00:15:03,070
verament jikkorrelataw għal funzjoni hash.

285
00:15:03,070 --> 00:15:08,900
Huwa biss mod biex tiddeċiedi liema
barmil inti element qed tmur fi, OK?

286
00:15:08,900 --> 00:15:14,850
Allura għal dan pset, inti tista 'tfittex up
pretty ħafna xi funzjoni hash tixtieq.

287
00:15:14,850 --> 00:15:16,030
>> Ma għandhom ikunu tiegħek stess.

288
00:15:16,030 --> 00:15:21,140
Hemm xi dawk verament jibred out
hemmhekk li jagħmlu kull tip ta matematika crazy.

289
00:15:21,140 --> 00:15:25,170
U jekk inti tixtieq li tagħmel tiegħek
spellchecker super fast,

290
00:15:25,170 --> 00:15:27,620
Nixtieq definittivament
tħares lejn wieħed minn dawn.

291
00:15:27,620 --> 00:15:32,390
>> Imma hemm ukoll l-
dawk sempliċi, bħal jikkomputa

292
00:15:32,390 --> 00:15:39,010
is-somma tal-kliem, bħal
kull ittra għandha numru.

293
00:15:39,010 --> 00:15:39,940
Kkalkulata l-ammont.

294
00:15:39,940 --> 00:15:42,230
Li jiddetermina l-barmil.

295
00:15:42,230 --> 00:15:45,430
Huma għandhom ukoll dawk faċli li
huma biss simili kollha tal-li A hawn,

296
00:15:45,430 --> 00:15:47,050
kollha tal-B hawnhekk.

297
00:15:47,050 --> 00:15:48,920
Kwalunkwe wieħed minn dawk.

298
00:15:48,920 --> 00:15:55,770
>> Bażikament, hija biss jgħidlek liema
indiċi array element tiegħek għandhom imorru fis.

299
00:15:55,770 --> 00:15:58,690
Just tiddeċiedi l-bucket--
dan kollu funzjoni hash huwa.

300
00:15:58,690 --> 00:16:04,180
Allura hawnhekk għandna eżempju li hija
biss l-ewwel ittra tas-sekwenza

301
00:16:04,180 --> 00:16:05,900
li I kien biss jitkellem dwar.

302
00:16:05,900 --> 00:16:11,900
>> Hekk ikollok xi hash li jinsab biss l-
ewwel ittra ta 'sekwenza tiegħek minus A,

303
00:16:11,900 --> 00:16:16,090
li se jagħtuk xi
numru bejn 0 u 25.

304
00:16:16,090 --> 00:16:20,790
U dak li trid tagħmel hu li
kun żgur li dan jirrappreżenta

305
00:16:20,790 --> 00:16:24,110
id-daqs tal-hash tiegħek table--
kemm bramel hemm.

306
00:16:24,110 --> 00:16:25,860
Ma 'ħafna minn dawn
funzjonijiet hash, dawn qed

307
00:16:25,860 --> 00:16:31,630
ser ikunu valuri jirritorna li tista
ikun ferm ogħla mill-għadd ta 'bramel

308
00:16:31,630 --> 00:16:33,610
li inti fil-fatt ikollhom
fit-tabella hash tiegħek,

309
00:16:33,610 --> 00:16:37,240
sabiex inti għandek bżonn tagħmel
żgur u MoD minn dawk.

310
00:16:37,240 --> 00:16:42,190
Inkella, li għaddej biex jgħidu,
oh, għandha tkun fil-barmil 5,000

311
00:16:42,190 --> 00:16:46,040
imma inti biss għandek 30
bramel fit-tabella hash tiegħek.

312
00:16:46,040 --> 00:16:49,360
U ovvjament, aħna lkoll nafu li l-
se jirriżulta xi żbalji crazy.

313
00:16:49,360 --> 00:16:52,870
Sabiex tagħmel ċert li Mod mill-
daqs tal-mejda hash tiegħek.

314
00:16:52,870 --> 00:16:58,430

315
00:16:58,430 --> 00:16:58,930
Kessaħ.

316
00:16:58,930 --> 00:17:00,506
Hekk kolliżjonijiet.

317
00:17:00,506 --> 00:17:02,620
Huwa kulħadd tajba s'issa?

318
00:17:02,620 --> 00:17:03,120
Mmhmm?

319
00:17:03,120 --> 00:17:05,900
>> UDJENZA: Għaliex kieku dan
ritorn ta 'tali valur enormi?

320
00:17:05,900 --> 00:17:09,210
>> SPEAKER 1: Jiddependi fuq l-algoritmu
dik il-funzjoni hash tiegħek juża.

321
00:17:09,210 --> 00:17:12,270
Xi wħud minnhom se do
multiplikazzjoni crazy.

322
00:17:12,270 --> 00:17:16,270
U dan kollu dwar jkollna
distribuzzjoni li,

323
00:17:16,270 --> 00:17:18,490
sabiex ikunu jagħmlu xi verament
affarijiet crazy kultant.

324
00:17:18,490 --> 00:17:20,960
Li kollox.

325
00:17:20,960 --> 00:17:22,140
Xi ħaġa oħra?

326
00:17:22,140 --> 00:17:22,829
OK.

327
00:17:22,829 --> 00:17:24,480
>> Hekk kolliżjonijiet.

328
00:17:24,480 --> 00:17:29,270
Bażikament, kif għidt qabel,
fix-xenarju aħjar każ,

329
00:17:29,270 --> 00:17:32,040
kwalunkwe barmil I tħares lejn huwa
se jkollhom ħaġa waħda,

330
00:17:32,040 --> 00:17:34,160
so I ma jkollhom ħarsa fil-livelli kollha, id-dritt?

331
00:17:34,160 --> 00:17:37,040
I jew taf huwa hemmhekk jew huwa
mhux, u dak hu li aħna verament irridu.

332
00:17:37,040 --> 00:17:43,960
Imma jekk ikollna għexieren ta 'eluf ta'
punti tad-data u inqas minn dak in-numru

333
00:17:43,960 --> 00:17:48,700
ta 'bramel, aħna qed tmur biex ikollhom
kolliżjonijiet fejn eventwalment xi ħaġa

334
00:17:48,700 --> 00:17:54,210
se jkollhom jispiċċaw fil-
barmil li diġà għandu element.

335
00:17:54,210 --> 00:17:57,390
>> Għalhekk il-kwistjoni hija, dak
nagħmlu f'dak il-każ?

336
00:17:57,390 --> 00:17:58,480
X'nagħmlu?

337
00:17:58,480 --> 00:17:59,300
Aħna diġà għandhom xi ħaġa hemmhekk?

338
00:17:59,300 --> 00:18:00,060
Do we biss tarmi it out?

339
00:18:00,060 --> 00:18:00,700
>> No

340
00:18:00,700 --> 00:18:01,980
Għandna biex iżommu tnejn minnhom.

341
00:18:01,980 --> 00:18:06,400
Allura l-mod li aħna
tipikament tagħmel dan huwa dak?

342
00:18:06,400 --> 00:18:08,400
X'inhu l-istruttura tad-data
aħna biss tkellem dwar?

343
00:18:08,400 --> 00:18:09,316
UDJENZA: lista Marbuta.

344
00:18:09,316 --> 00:18:10,500
SPEAKER 1: Lista marbuta.

345
00:18:10,500 --> 00:18:16,640
Allura issa, minflok ta 'kull wieħed minn dawn
bramel biss li element wieħed,

346
00:18:16,640 --> 00:18:24,020
li għaddej biex jkun fih lista marbuta ta '
l-elementi li ġew hashed fis dan.

347
00:18:24,020 --> 00:18:27,588
OK, ma kulħadd tip ta 'nikseb dik l-idea?

348
00:18:27,588 --> 00:18:30,546
Għaliex aħna ma jista 'jkollha firxa
għaliex aħna ma jafux kif ħafna affarijiet

349
00:18:30,546 --> 00:18:31,730
ser ikunu fil hemmhekk.

350
00:18:31,730 --> 00:18:36,540
Lista marbuta jippermetti li
għadek in-numru eżatt li

351
00:18:36,540 --> 00:18:38,465
huma hashed f'dak barmil, id-dritt?

352
00:18:38,465 --> 00:18:42,260

353
00:18:42,260 --> 00:18:50,500
>> Allura lineari probing huwa
bażikament dan idea--

354
00:18:50,500 --> 00:18:52,300
huwa mod wieħed biex jittrattaw ħabta.

355
00:18:52,300 --> 00:18:58,010
X'tista 'tagħmel hija jekk, f'dan il-
każ, berry kien hashed fis 1

356
00:18:58,010 --> 00:19:01,130
u diġà għandna
xi ħaġa hemmhekk, inti biss

357
00:19:01,130 --> 00:19:04,840
iżommu għaddejjin isfel sakemm
issib slot vojta.

358
00:19:04,840 --> 00:19:06,370
C'est mod wieħed biex jimmaniġġaw dan.

359
00:19:06,370 --> 00:19:09,020
Il-mod ieħor biex jimmaniġġaw
huwa ma dak li aħna biss

360
00:19:09,020 --> 00:19:12,280
called-- il marbut
lista tissejjaħ chaining.

361
00:19:12,280 --> 00:19:20,510
>> Allura din l-idea xogħlijiet jekk
tabella hash tiegħek taħseb

362
00:19:20,510 --> 00:19:24,150
huwa ħafna ikbar minn
data tiegħek sett jew jekk inti

363
00:19:24,150 --> 00:19:28,870
jridu jippruvaw u jimminimizzaw ikkatenar
sakemm huwa assolutament neċessarju.

364
00:19:28,870 --> 00:19:34,050
Allura ħaġa waħda hija lineari
probing ovvjament ifisser

365
00:19:34,050 --> 00:19:37,290
dik il-funzjoni hash tiegħek
mhux daqshekk utli

366
00:19:37,290 --> 00:19:42,200
għaliex int ser jispiċċaw jużaw
funzjoni hash tiegħek, jkollna sa punt,

367
00:19:42,200 --> 00:19:46,400
inti lineari sonda isfel sa
xi post li hija disponibbli.

368
00:19:46,400 --> 00:19:49,670
Imma issa, naturalment, xejn
inkella li jispiċċa hemm,

369
00:19:49,670 --> 00:19:52,050
int ser ikollhom
tfittxija anke aktar 'l isfel.

370
00:19:52,050 --> 00:19:55,650
>> U hemm ħafna aktar
spejjeż tat-tiftix li

371
00:19:55,650 --> 00:19:59,820
tmur fil inputjar element
fit-tabella hash tiegħek issa, id-dritt?

372
00:19:59,820 --> 00:20:05,640
U issa meta inti tmur u jippruvaw isibu
berry darb'oħra, int ser issir hash lilha,

373
00:20:05,640 --> 00:20:07,742
u li għaddej biex jgħidu,
oh, ħarsa fil barmil 1,

374
00:20:07,742 --> 00:20:09,700
u mhuwiex ser ikun
fil-barmil 1, hekk int

375
00:20:09,700 --> 00:20:11,970
ser ikollhom travers
permezz tal-bqija ta 'dawn.

376
00:20:11,970 --> 00:20:17,720
Allura huwa kultant utli,
iżda f'ħafna każijiet,

377
00:20:17,720 --> 00:20:22,660
aħna qed tmur biex ngħid li
chaining huwa dak li inti trid tagħmel.

378
00:20:22,660 --> 00:20:25,520
>> Allura aħna tkellimna dwar dan qabel.

379
00:20:25,520 --> 00:20:27,812
I ltqajna l quddiem ftit ta 'myself.

380
00:20:27,812 --> 00:20:33,560
Iżda chaining huwa bażikament dak
kull barmil fit-tabella hash tiegħek

381
00:20:33,560 --> 00:20:36,120
huwa biss lista marbuta.

382
00:20:36,120 --> 00:20:39,660
>> Allura mod ieħor, jew aktar tekniċi
mod, biex jaħsbu ta 'tabella hash

383
00:20:39,660 --> 00:20:44,490
hija li huwa biss firxa
ta 'listi marbuta, li

384
00:20:44,490 --> 00:20:49,330
meta int bil-miktub dizzjunarju tiegħek
u inti qed tipprova tagħbija,

385
00:20:49,330 --> 00:20:52,070
ħsieb ta 'dan bħala
firxa ta 'listi marbuta

386
00:20:52,070 --> 00:20:54,390
se tagħmilha aktar faċli
għalik biex initialize.

387
00:20:54,390 --> 00:20:57,680
>> UDJENZA: Allura tabella hash
għandu daqs predeterminat,

388
00:20:57,680 --> 00:20:58,980
bħal [inaudible] tal bramel?

389
00:20:58,980 --> 00:20:59,220
>> SPEAKER 1: Dritt.

390
00:20:59,220 --> 00:21:01,655
Għalhekk għandha numru sett ta '
bramel li inti determine--

391
00:21:01,655 --> 00:21:03,530
li inti guys għandhom
tħossok liberu li jilagħbu bil.

392
00:21:03,530 --> 00:21:05,269
Jista 'jkun pjuttost jibred
biex tara x'jiġri

393
00:21:05,269 --> 00:21:06,810
kif int bdilt numru tiegħek ta 'bramel.

394
00:21:06,810 --> 00:21:09,410

395
00:21:09,410 --> 00:21:11,510
Iżda yeah, hija għandha
sett numru ta 'bramel.

396
00:21:11,510 --> 00:21:15,360
Dak li jippermetti li inti tajbin bħala
ħafna elementi kif għandek bżonn

397
00:21:15,360 --> 00:21:19,350
huwa fejn dan chaining separata inti
jkunu marbuta listi f'kull barmil.

398
00:21:19,350 --> 00:21:22,850
Dan ifisser tabella hash tiegħek
se tkun eżattament id-daqs

399
00:21:22,850 --> 00:21:25,440
li inti jeħtieġ li tkun, id-dritt?

400
00:21:25,440 --> 00:21:27,358
Dik hija l-punt kollu ta 'listi marbuta.

401
00:21:27,358 --> 00:21:30,850

402
00:21:30,850 --> 00:21:32,480
Kessaħ.

403
00:21:32,480 --> 00:21:38,780
>> Allura kulħadd OK hemmhekk?

404
00:21:38,780 --> 00:21:39,801
Kull dritt.

405
00:21:39,801 --> 00:21:40,300
Ah.

406
00:21:40,300 --> 00:21:41,860
Dak li ġara biss?

407
00:21:41,860 --> 00:21:42,960
Verament issa.

408
00:21:42,960 --> 00:21:45,250
Aqta 'xi ħadd qtil lili.

409
00:21:45,250 --> 00:21:52,060
>> OK aħna qed tmur biex jmorru fil
tentattivi, li huma ftit crazy.

410
00:21:52,060 --> 00:21:53,140
I simili tabelli hash.

411
00:21:53,140 --> 00:21:54,460
Jien naħseb li qed verament jibred.

412
00:21:54,460 --> 00:21:56,710
Jipprova huma jibred, wisq.

413
00:21:56,710 --> 00:21:59,590
>> Sabiex ħadd ma tiftakar dak jipprova hu?

414
00:21:59,590 --> 00:22:01,740
Għandek mxew fuq
fil-qosor fil-lecture?

415
00:22:01,740 --> 00:22:04,570

416
00:22:04,570 --> 00:22:06,377
Do you remember-tip ta 'kif taħdem?

417
00:22:06,377 --> 00:22:08,460
UDJENZA: Jien biss nodding
li aħna ma jmorru fuq dan.

418
00:22:08,460 --> 00:22:09,626
SPEAKER 1: We do jmorru fuq dan.

419
00:22:09,626 --> 00:22:13,100
OK, aħna qed verament se jmorru
fuq issa huwa dak li aħna qed tgħid.

420
00:22:13,100 --> 00:22:14,860
>> UDJENZA: Li għal siġra irkupru.

421
00:22:14,860 --> 00:22:15,280
>> SPEAKER 1: Yeah.

422
00:22:15,280 --> 00:22:16,196
Huwa siġra irkupru.

423
00:22:16,196 --> 00:22:16,960
Biża.

424
00:22:16,960 --> 00:22:23,610
Allura ħaġa waħda li l-avviż hawnhekk hija li aħna
qed iħarsu lejn karattri individwali

425
00:22:23,610 --> 00:22:24,480
hawn, id-dritt?

426
00:22:24,480 --> 00:22:29,710
>> Allura qabel b'funzjoni hash tagħna, aħna
kienu qed ifittxu fil-kliem kollha kemm hi,

427
00:22:29,710 --> 00:22:32,270
u issa aħna qed tfittex aktar
fil-karattri, right?

428
00:22:32,270 --> 00:22:38,380
Allura aħna għandna Maxwell hawn fuq u Mendel.

429
00:22:38,380 --> 00:22:47,840
Allura bażikament try-- mod biex jaħsbu
dwar dan hija li kull livell hawn

430
00:22:47,840 --> 00:22:49,000
firxa ta 'ittri.

431
00:22:49,000 --> 00:22:53,310

432
00:22:53,310 --> 00:22:55,790
Allura dan huwa node għerq tiegħek hawn, id-dritt?

433
00:22:55,790 --> 00:23:01,980
Dan għandu l-karattri tal-
alfabett għall-bidu ta 'kull kelma.

434
00:23:01,980 --> 00:23:06,480
>> U dak li trid tagħmel hu li
jiġifieri, OK, aħna għandna xi kelma M.

435
00:23:06,480 --> 00:23:10,590
Aħna qed tmur biex tfittex Maxwell, hekk
immorru 'M. u M-punti lill-impjegati whole

436
00:23:10,590 --> 00:23:14,800
oħra firxa fejn kull
kelma, sakemm ikun hemm

437
00:23:14,800 --> 00:23:17,044
hija kelma li għandha
bħala t-tieni ittra,

438
00:23:17,044 --> 00:23:19,460
sakemm hemm kelma li
għandha B bħala t-tieni ittra,

439
00:23:19,460 --> 00:23:24,630
din se jkollha pointer
jmorru għal xi firxa li jmiss.

440
00:23:24,630 --> 00:23:29,290
>> Hemm probabilment mhux
kelma li xi ħaġa MP,

441
00:23:29,290 --> 00:23:32,980
hekk fil-pożizzjoni P f'dan
firxa, ikun biss NULL.

442
00:23:32,980 --> 00:23:38,840
Hija ngħid, OK, m'hemm l-ebda kelma
li M segwit minn P, OK?

443
00:23:38,840 --> 00:23:43,100
Allura jekk aħna taħseb dwarha, kull
wieħed minn dawn l-affarijiet iżgħar

444
00:23:43,100 --> 00:23:47,990
huwa attwalment wieħed minn dawn
arrays kbar mill A permezz Z.

445
00:23:47,990 --> 00:23:55,064
Allura dak li jista 'jkun waħda mill-affarijiet
li huwa tip ta 'żvantaġġ ta jipprova?

446
00:23:55,064 --> 00:23:56,500
>> UDJENZA: A lott ta 'memorja.

447
00:23:56,500 --> 00:23:59,940
>> SPEAKER 1: Huwa ton ta 'memorja, id-dritt?

448
00:23:59,940 --> 00:24:08,750
Kull waħda minn dawn il-blokok hawn
jirrappreżenta 26 spazji, 26 element array.

449
00:24:08,750 --> 00:24:13,680
Allura tipprova tikseb oerhört tqil ispazju.

450
00:24:13,680 --> 00:24:17,100
>> Iżda huma malajr ħafna.

451
00:24:17,100 --> 00:24:22,540
Allura oerhört mgħaġġel iżda
verament ispazju ineffiċjenti.

452
00:24:22,540 --> 00:24:24,810
Tip ta 'għandek figura
out liema waħda tixtieq.

453
00:24:24,810 --> 00:24:29,470
Dawn huma verament jiksaħ għal pset tiegħek,
iżda dawn ma jieħdu ħafna ta 'memorja,

454
00:24:29,470 --> 00:24:30,290
sabiex inti kummerċ off.

455
00:24:30,290 --> 00:24:31,480
Yeah?

456
00:24:31,480 --> 00:24:34,300
>> UDJENZA: Ikun possibbli
li jitwaqqaf jipprova u mbagħad

457
00:24:34,300 --> 00:24:37,967
ladarba inti għandek l-
data fiha li inti need--

458
00:24:37,967 --> 00:24:39,550
I do not know jekk dan jagħmel sens.

459
00:24:39,550 --> 00:24:42,200
I kien jwarrbu l-
Karattri NULL, iżda mbagħad

460
00:24:42,200 --> 00:24:42,910
inti ma tkunx kapaċi indiċi them--

461
00:24:42,910 --> 00:24:43,275
>> SPEAKER 1: Inti xorta jkollok bżonn lilhom.

462
00:24:43,275 --> 00:24:44,854
>> UDJENZA: - bl-istess mod kull darba.

463
00:24:44,854 --> 00:24:45,520
SPEAKER 1: Yeah.

464
00:24:45,520 --> 00:24:50,460
Ikollok bżonn l-karattri NULL let
inti taf jekk hemm Ma kelma hemmhekk.

465
00:24:50,460 --> 00:24:52,040
Ben kellek xi ħaġa li trid?

466
00:24:52,040 --> 00:24:52,540
OK.

467
00:24:52,540 --> 00:24:54,581
Kull dritt, hekk aħna qed tmur
li jmorru ftit aktar

468
00:24:54,581 --> 00:24:58,920
fil-dettalji tekniċi wara
jipprova u joperaw permezz ta 'eżempju.

469
00:24:58,920 --> 00:25:01,490
>> OK, għalhekk dan huwa l-istess ħaġa.

470
00:25:01,490 --> 00:25:06,290
Billi fil-lista marbuta, prinċipali tagħna
tip of-- x'inhu l-kelma Irrid? -

471
00:25:06,290 --> 00:25:08,350
bħall-bini blokk kien node.

472
00:25:08,350 --> 00:25:12,280
Fil jipprova, aħna għandna wkoll node,
imma hija definita b'mod differenti.

473
00:25:12,280 --> 00:25:17,000
>> Allura aħna għandna xi BOOL li
tirrappreżenta jekk kelma attwalment

474
00:25:17,000 --> 00:25:23,530
jeżisti dan il-post, u mbagħad
għandna xi firxa here-- jew pjuttost,

475
00:25:23,530 --> 00:25:27,840
dan huwa pointer għal
firxa ta '27 karattri.

476
00:25:27,840 --> 00:25:33,339
U dan huwa għal, f'dan il-każ, din
27-- Jien ċert kollha inti simili, stenna,

477
00:25:33,339 --> 00:25:34,880
hemm 26-ittri fil-alfabett.

478
00:25:34,880 --> 00:25:36,010
Għalfejn għandna 27?

479
00:25:36,010 --> 00:25:37,870
>> Allura jiddependi fuq il-
mod inti jimplimentaw din,

480
00:25:37,870 --> 00:25:43,240
dan huwa minn pset li
permessi għall apostrophes.

481
00:25:43,240 --> 00:25:46,010
Allura hu għalhekk li l-waħda żejda.

482
00:25:46,010 --> 00:25:50,500
Int ser ikollok wkoll f'xi wħud
każijiet il-terminatur null

483
00:25:50,500 --> 00:25:53,230
hija nkluża bħala waħda mill-
karattri li huwa permess li jkun,

484
00:25:53,230 --> 00:25:56,120
u li kif jivverifikaw li
tara jekk huwa l-aħħar tal-kelma.

485
00:25:56,120 --> 00:26:01,340
Jekk int interessat, check out
Video Kevin dwar study.cs50,

486
00:26:01,340 --> 00:26:04,790
kif ukoll Wikipedija għandha
xi riżorsi tajbin hemmhekk.

487
00:26:04,790 --> 00:26:09,000
>> Iżda aħna qed tmur biex jgħaddu biss tip
ta 'kif inti tista' taħdem permezz jipprova

488
00:26:09,000 --> 00:26:11,010
jekk int tingħata waħda.

489
00:26:11,010 --> 00:26:16,230
Allura aħna għandna waħda super sempliċi hawnhekk li
għandha l-kliem "BAT" u "zoom" fihom.

490
00:26:16,230 --> 00:26:18,920
U kif naraw up here,
dan l-ispazju ftit hawn

491
00:26:18,920 --> 00:26:22,560
jirrappreżenta BOOL tagħna li
jgħid, iva, dan huwa kelma.

492
00:26:22,560 --> 00:26:27,060
U allura dan għandu tagħna
arrays ta 'karattri, id-dritt?

493
00:26:27,060 --> 00:26:33,480
>> Allura aħna se jmorru permezz
sejba "BAT" f'dan jipprova.

494
00:26:33,480 --> 00:26:38,340
Allura tibda fil-quċċata, id-dritt?

495
00:26:38,340 --> 00:26:46,290
U aħna nafu li b jikkorrispondi għal
it-tieni indiċi, it-tieni element

496
00:26:46,290 --> 00:26:47,840
f'dan array, għaliex u b.

497
00:26:47,840 --> 00:26:51,340
Allura madwar it-tieni wieħed.

498
00:26:51,340 --> 00:26:58,820
>> U jgħid, OK, berred, segwi dan in
l-array li jmiss, għaliex jekk aħna niftakru,

499
00:26:58,820 --> 00:27:02,160
mhuwiex li kull wieħed minn dawn
attwalment fiha l-element.

500
00:27:02,160 --> 00:27:07,110
Kull wieħed minn dawn arrays
fih pointer, id-dritt?

501
00:27:07,110 --> 00:27:10,030
Huwa distinzjoni importanti biex jagħmlu.

502
00:27:10,030 --> 00:27:13,450
>> Naf li dan se be-- jipprova huma
verament diffiċli biex jiksbu fuq l-ewwel darba,

503
00:27:13,450 --> 00:27:15,241
hekk anke jekk dan huwa l-
tieni jew it-tielet darba

504
00:27:15,241 --> 00:27:18,370
u huwa għadu tip
ta seeming diffiċli,

505
00:27:18,370 --> 00:27:21,199
I wegħda jekk inti tmur watch
l-qasir għal darb'oħra għada,

506
00:27:21,199 --> 00:27:22,740
inneħħu probabbilment jagħmlu sens ħafna aktar.

507
00:27:22,740 --> 00:27:23,890
Huwa jieħu ħafna biex diġestiva.

508
00:27:23,890 --> 00:27:27,800
I still kultant am
simili, stenna, dak li huwa jipprova?

509
00:27:27,800 --> 00:27:29,080
Kif nista jużaw dan?

510
00:27:29,080 --> 00:27:33,880
>> Allura għandna b f'dan il-każ,
li hija t-tieni indiċi tagħna.

511
00:27:33,880 --> 00:27:40,240
Jekk kellna, jiġifieri, C jew
d jew kull ittra oħra,

512
00:27:40,240 --> 00:27:45,810
għandna bżonn li Mappa li lura għall-indiċi
ta 'firxa tagħna li dan jikkorrispondi għal.

513
00:27:45,810 --> 00:27:56,930
Allura aħna se tieħu bħal rchar u aħna biss
naqqas off biex iħażżu fis 0-25.

514
00:27:56,930 --> 00:27:58,728
Kulħadd tajba kif aħna
Mappa karattri tagħna?

515
00:27:58,728 --> 00:28:00,440
OK.

516
00:28:00,440 --> 00:28:05,980
>> Allura immorru għat-tieni waħda u aħna
tara li, iva, huwa ma NULL.

517
00:28:05,980 --> 00:28:07,780
Aħna tista 'timxi fuq dan array li jmiss.

518
00:28:07,780 --> 00:28:12,300
Allura aħna jmorru fuq għal din array li jmiss hawn.

519
00:28:12,300 --> 00:28:15,500
>> U aħna ngħidu, OK, issa aħna
bżonn biex tara jekk huwa hawnhekk.

520
00:28:15,500 --> 00:28:18,590
Huwa A null jew ma dan
attwalment jimxu 'l quddiem?

521
00:28:18,590 --> 00:28:21,880
Allura fil-fatt jiċċaqlaq
jgħaddi f'din firxa.

522
00:28:21,880 --> 00:28:24,570
U aħna ngħidu, OK, t hija l-aħħar ittra tagħna.

523
00:28:24,570 --> 00:28:27,580
Allura immorru l-t fil-indiċi.

524
00:28:27,580 --> 00:28:30,120
U allura aħna nimxu 'l quddiem
għaliex hemm wieħed ieħor.

525
00:28:30,120 --> 00:28:38,340
U dan wieħed jgħid bażikament li, iva,
jgħid li hemm kelma here--

526
00:28:38,340 --> 00:28:41,750
li jekk inti ssegwi dan
triq, inti jkunu waslu

527
00:28:41,750 --> 00:28:43,210
fi ftit kliem, li nafu huwa "BAT."

528
00:28:43,210 --> 00:28:43,800
Iva?

529
00:28:43,800 --> 00:28:46,770
>> UDJENZA: Huwa standard li jkollhom dik
bħala indiċi 0 u mbagħad ikollhom tip ta '1

530
00:28:46,770 --> 00:28:47,660
jew li jkollu fl-aħħar?

531
00:28:47,660 --> 00:28:48,243
>> SPEAKER 1: No

532
00:28:48,243 --> 00:28:55,360
Mela jekk inħarsu lura lejn tagħna
dikjarazzjoni hawn, huwa BOOL,

533
00:28:55,360 --> 00:28:59,490
dan huwa element tagħha stess fil node tiegħek.

534
00:28:59,490 --> 00:29:03,331
Dan mhuwiex parti mill-firxa.

535
00:29:03,331 --> 00:29:03,830
Kessaħ.

536
00:29:03,830 --> 00:29:08,370
Allura meta aħna finitura kelma tagħna u aħna qed
f'dan array, dak li rridu nagħmlu

537
00:29:08,370 --> 00:29:12,807
hija tagħmel verifika għal dan huwa kelma.

538
00:29:12,807 --> 00:29:14,390
U f'dan il-każ, ikun ritorn iva.

539
00:29:14,390 --> 00:29:17,220

540
00:29:17,220 --> 00:29:24,090
>> Allura fuq din in-nota, aħna nafu li "zoo" -
nafu bħala bnedmin li "zoo" hija kelma,

541
00:29:24,090 --> 00:29:24,820
dritt?

542
00:29:24,820 --> 00:29:28,990
Iżda huma jippruvaw hawnhekk
jgħidu, l-ebda, mhuwiex.

543
00:29:28,990 --> 00:29:33,980
U ngħid li għaliex aħna
ma jkunux ħatru bħala kelma hawn.

544
00:29:33,980 --> 00:29:40,440
Anki jekk nistgħu travers
permezz ta 'dan array,

545
00:29:40,440 --> 00:29:43,890
dan jipprova ngħid li, no,
zoo ma jkunx dizzjunarju tiegħek

546
00:29:43,890 --> 00:29:47,070
għaliex għandna ma
nnominata bħala tali.

547
00:29:47,070 --> 00:29:52,870
>> Allura mod wieħed biex tagħmel that--
oh, sorry, dan wieħed.

548
00:29:52,870 --> 00:29:59,450
Allura f'dan il-każ, "zoo" mhijiex
kelma, imma huwa fl jipprova tagħna.

549
00:29:59,450 --> 00:30:05,690
Iżda f'dan il-wieħed, ngħidu aħna jriduhom
jintroduċu l-kelma "banju," dak li jiġri

550
00:30:05,690 --> 00:30:08,260
hija aħna isegwu through-- b, a, t.

551
00:30:08,260 --> 00:30:11,820
Aħna f'dan array, u
immorru tiftix għal h.

552
00:30:11,820 --> 00:30:15,220
>> F'dan il-każ, meta aħna
tħares lejn il-pointer fuq h,

553
00:30:15,220 --> 00:30:17,890
huwa tipponta lejn NULL, OK?

554
00:30:17,890 --> 00:30:20,780
Allura sakemm huwa espliċitament
tipponta lejn firxa ieħor,

555
00:30:20,780 --> 00:30:25,000
għandek tassumi li l-pointers
f'dan array huma tipponta lejn nulla.

556
00:30:25,000 --> 00:30:28,270
Allura f'dan il-każ, h hija li tipponta
biex nulla hekk aħna ma tistax tagħmel xejn,

557
00:30:28,270 --> 00:30:31,540
għalhekk ikun ukoll ritorn
falza, "banju" mhijiex fil hawn.

558
00:30:31,540 --> 00:30:34,102

559
00:30:34,102 --> 00:30:35,810
Allura issa aħna qed attwalment
se jmorru permezz

560
00:30:35,810 --> 00:30:39,790
kif kieku għandna attwalment ngħid
li "zoo" hija fil jippruvaw tagħna.

561
00:30:39,790 --> 00:30:42,920
Kif nistgħu daħħal "zoo" fis jipprova tagħna?

562
00:30:42,920 --> 00:30:47,810
Allura bl-istess mod li bdejna ma '
lista marbuta tagħna, aħna tibda fil-għerq.

563
00:30:47,810 --> 00:30:50,600
Meta fid-dubju, tibda fil
l-għerq ta 'dawn l-affarijiet.

564
00:30:50,600 --> 00:30:53,330
>> U aħna ser ngħidu, OK, z.

565
00:30:53,330 --> 00:30:55,650
z teżisti f'dan, u ma.

566
00:30:55,650 --> 00:30:58,370
Allura inti qed jimxu fuq
firxa jmiss tiegħek, OK?

567
00:30:58,370 --> 00:31:01,482
U mbagħad fuq il-wieħed li jmiss,
ngħidu, OK, ma o jeżistu?

568
00:31:01,482 --> 00:31:03,000
Hija ma.

569
00:31:03,000 --> 00:31:04,330
Dan jerġa.

570
00:31:04,330 --> 00:31:08,670
>> U hekk dak li jmiss tagħna, konna qal,
OK, "zoo" diġà jeżisti hawnhekk.

571
00:31:08,670 --> 00:31:12,440
Kollha għandna bżonn tagħmel huwa stabbilit dan ugwali
li veru, li hemm kelma hemmhekk.

572
00:31:12,440 --> 00:31:15,260
Jekk inti kienu segwiti kollox
sa qabel dak il-punt,

573
00:31:15,260 --> 00:31:17,030
huwa kelma, hekk biss
huwa stabbilit ugwali għal tali.

574
00:31:17,030 --> 00:31:17,530
Iva?

575
00:31:17,530 --> 00:31:22,550
>> UDJENZA: Mela allura ma li
jfisser li "BA" hija kelma wkoll?

576
00:31:22,550 --> 00:31:24,120
>> SPEAKER 1: No

577
00:31:24,120 --> 00:31:28,870
Allura f'dan il-każ, "ba" aħna se tikseb
hawnhekk, aħna ngħid huwa kelma,

578
00:31:28,870 --> 00:31:31,590
u xorta jkun hemm ebda.

579
00:31:31,590 --> 00:31:32,822
OK?

580
00:31:32,822 --> 00:31:33,740
Mmhmm?

581
00:31:33,740 --> 00:31:36,360
>> UDJENZA: Allura ladarba inti ma hija
kelma u inti tgħidli iva, allura huwa

582
00:31:36,360 --> 00:31:38,380
se jkun fihom biex tmur m?

583
00:31:38,380 --> 00:31:42,260
>> SPEAKER 1: Allura dan għandu ma
with-- int tagħbija dan fil.

584
00:31:42,260 --> 00:31:43,640
You say "zoo" hija kelma.

585
00:31:43,640 --> 00:31:47,020
Meta inti tmur check--
bħal, ngħidu li inti trid tgħid,

586
00:31:47,020 --> 00:31:49,400
ma "zoo" jeżistu f'dan dizzjunarju?

587
00:31:49,400 --> 00:31:54,200
Int biss tmur biex tfittex għal "zoo,"
u mbagħad tiċċekkja biex tara jekk huwa kelma.

588
00:31:54,200 --> 00:31:57,291
Inti qatt ma ser jiċċaqalqu
permezz ta 'm għaliex li mhux

589
00:31:57,291 --> 00:31:58,290
dak li qed tfittex.

590
00:31:58,290 --> 00:32:02,690

591
00:32:02,690 --> 00:32:08,070
>> Hekk jekk aħna fil-fatt riedu
żid "banju" fis dan jipprova,

592
00:32:08,070 --> 00:32:11,390
aħna se nagħmlu l-istess ħaġa
kif għamilna ma "zoo,"

593
00:32:11,390 --> 00:32:15,380
ħlief aħna se tara li meta aħna
tipprova u tikseb sabiex h, dan ma jeżistix.

594
00:32:15,380 --> 00:32:20,090
Allura inti tista 'taħseb ta' dan bħala jippruvaw
li żżid node ġdid ġo lista marbuta,

595
00:32:20,090 --> 00:32:27,210
hekk aħna se bżonn li żżid ieħor
waħda minn dawn arrays, bħal hekk.

596
00:32:27,210 --> 00:32:35,670
U allura dak li nagħmlu huwa aħna biss stabbiliti l-h
element ta 'dan array li tipponta lejn dan.

597
00:32:35,670 --> 00:32:39,430
>> U allura dak li rridu nagħmlu hawn?

598
00:32:39,430 --> 00:32:43,110
Iżżidhiex ugwali għal veru
għaliex dan huwa kelma.

599
00:32:43,110 --> 00:32:46,350

600
00:32:46,350 --> 00:32:48,150
Kessaħ.

601
00:32:48,150 --> 00:32:48,700
I know.

602
00:32:48,700 --> 00:32:51,170
Tipprova mhumiex l-aktar eċċitanti.

603
00:32:51,170 --> 00:32:54,250
Trust me, I know.

604
00:32:54,250 --> 00:32:58,040
>> Allura ħaġa waħda li tirrealizza ma tentattivi,
I said, dawn qed effiċjenti ħafna.

605
00:32:58,040 --> 00:33:00,080
Allura aħna stajt tidher li
jieħdu ton ta 'spazju.

606
00:33:00,080 --> 00:33:01,370
Huma qed tip ta 'konfużjoni.

607
00:33:01,370 --> 00:33:03,367
Allura għaliex kieku aħna qatt tuża dawn?

608
00:33:03,367 --> 00:33:05,450
Aħna nużaw dawn għaliex qed
oerhört effiċjenti.

609
00:33:05,450 --> 00:33:08,130
>> Mela jekk inti qed tfittex qatt
up kelma, inti biss

610
00:33:08,130 --> 00:33:10,450
li tmiss mit-tul tal-kelma.

611
00:33:10,450 --> 00:33:15,210
Mela jekk inti qed tfittex għal
kelma li huwa ta 'tul ħamsa,

612
00:33:15,210 --> 00:33:20,940
int biss qatt ser ikollhom
jagħmlu iktar ħames paraguni, OK?

613
00:33:20,940 --> 00:33:25,780
Hekk jagħmilha bażikament kostanti.

614
00:33:25,780 --> 00:33:29,150
Bħal inserzjoni u Lookup
huma bażikament ta 'żmien kostanti.

615
00:33:29,150 --> 00:33:33,750
>> Hekk jekk inti tista 'qatt tikseb
xi ħaġa fil-ħin kostanti,

616
00:33:33,750 --> 00:33:35,150
li bħala tajba kif jiġrilha.

617
00:33:35,150 --> 00:33:37,990
Inti ma tistax tikseb aħjar minn
ħin kostanti għal dawn l-affarijiet.

618
00:33:37,990 --> 00:33:43,150
Allura dan huwa wieħed mill-
pluses kbar ta 'jipprova.

619
00:33:43,150 --> 00:33:46,780
>> Iżda huwa ħafna spazju.

620
00:33:46,780 --> 00:33:50,380
Allura inti tip ta 'għandek tiddeċiedi
x'hemm aktar importanti għalik.

621
00:33:50,380 --> 00:33:54,700
U fuq il-kompjuters tal-lum, il-
ispazju li jipprova jista 'jieħu

622
00:33:54,700 --> 00:33:57,740
forsi ma jaffettwax
inti li ħafna, imma forsi

623
00:33:57,740 --> 00:34:01,350
int jittrattaw ma 'xi ħaġa
li għandha ħafna, ferm aktar affarijiet,

624
00:34:01,350 --> 00:34:02,810
u jipprova biss mhuwiex raġonevoli.

625
00:34:02,810 --> 00:34:03,000
Iva?

626
00:34:03,000 --> 00:34:05,610
>> UDJENZA: Stenna, hekk ikollok 26
ittri f'kull wieħed wieħed?

627
00:34:05,610 --> 00:34:07,440
>> SPEAKER 1: Mmhmm.

628
00:34:07,440 --> 00:34:08,570
Yeah, inti għandek 26.

629
00:34:08,570 --> 00:34:16,984
Inti għandek xi hija markatur kelma u mbagħad
għandek 26 pointers f'kull wieħed.

630
00:34:16,984 --> 00:34:17,775
U dawn qed point--

631
00:34:17,775 --> 00:34:20,280
>> UDJENZA: U kull 26,
ma għandhom kull wieħed ikollhom 26?

632
00:34:20,280 --> 00:34:21,500
>> SPEAKER 1: Iva.

633
00:34:21,500 --> 00:34:27,460
U hu għalhekk li, kif inti tista '
tara, hija tespandi pjuttost malajr.

634
00:34:27,460 --> 00:34:28,130
Kull dritt.

635
00:34:28,130 --> 00:34:32,524
Allura aħna qed tmur biex tikseb fis-siġar, li
Inħoss bħal huwa aktar faċli u probabbilment se

636
00:34:32,524 --> 00:34:36,150
jkun reprieve ftit sbieħ
minn jipprova hemmhekk.

637
00:34:36,150 --> 00:34:39,620
Hekk nisperaw ħafna minnkom
raw siġra qabel.

638
00:34:39,620 --> 00:34:41,820
Mhux bħall-pretty
dawk barra, li jiena

639
00:34:41,820 --> 00:34:44,340
ma nafx jekk xi ħadd
marru barra reċentement.

640
00:34:44,340 --> 00:34:49,230
I marru tuffieħ picking dan il-weekend,
u oh gosh tiegħi, kien sbieħ.

641
00:34:49,230 --> 00:34:52,250
Ma kontx naf weraq
tista 'tfittex li pretty.

642
00:34:52,250 --> 00:34:53,610
>> Allura din hija biss siġra, id-dritt?

643
00:34:53,610 --> 00:34:56,790
Huwa biss xi node, u
punti li mazz ta 'punti strateġiċi oħrajn.

644
00:34:56,790 --> 00:34:59,570
Kif qed taraw hawn, dan huwa
tip ta 'tema rikorrenti.

645
00:34:59,570 --> 00:35:03,720
Lymph tipponta lejn lymph huwa tip ta '
l-essenza ta 'strutturi ta' dejta ħafna.

646
00:35:03,720 --> 00:35:06,670
Hija biss tiddependi fuq kif aħna
jkollhom magħhom jippuntaw lejn xulxin

647
00:35:06,670 --> 00:35:08,600
u kif aħna travers
permezz tagħhom u kif aħna

648
00:35:08,600 --> 00:35:14,500
daħħal affarijiet li jiddetermina
karatteristiċi differenti tagħhom.

649
00:35:14,500 --> 00:35:17,600
>> Hekk biss xi terminoloġija,
li stajt użati qabel.

650
00:35:17,600 --> 00:35:20,010
Allura għeruq huwa dak kollu li huwa fil-quċċata ħafna.

651
00:35:20,010 --> 00:35:21,200
huwa fejn aħna dejjem tibda.

652
00:35:21,200 --> 00:35:23,610
Inti tista 'taħseb li bħala l-kap wkoll.

653
00:35:23,610 --> 00:35:28,750
Iżda għas-siġar, għandna t-tendenza li
jirreferu għaliha bħala l-għerq.

654
00:35:28,750 --> 00:35:32,820
>> Xejn fil-here-- qiegħ
fil-ħafna, ħafna bottom--

655
00:35:32,820 --> 00:35:34,500
huma weraq kkunsidrati.

656
00:35:34,500 --> 00:35:37,210
Għalhekk tmur flimkien mal-
ħaġa sħiħa siġra, id-dritt?

657
00:35:37,210 --> 00:35:39,860
Weraq huma fit-truf tal siġra tiegħek.

658
00:35:39,860 --> 00:35:45,820
>> U allura aħna wkoll jkollhom koppja ta '
termini li jitkellmu dwar lymph fir-rigward

659
00:35:45,820 --> 00:35:46,680
lil xulxin.

660
00:35:46,680 --> 00:35:49,700
Allura aħna għandna ġenitur,
tfal, u l-aħwa.

661
00:35:49,700 --> 00:35:56,260
Allura f'dan il-każ, 3 huwa l-
ġenitur ta '5, 6, u 7.

662
00:35:56,260 --> 00:36:00,370
Allura l-ġenitur huwa dak kollu li huwa
pass wieħed hawn fuq x'ikun int

663
00:36:00,370 --> 00:36:02,940
jirreferu għal, hekk biss
bħal siġra tal-familja.

664
00:36:02,940 --> 00:36:07,090
Nisperaw, din hija kollha ftit
ftit aktar intuwittivi mill-jipprova.

665
00:36:07,090 --> 00:36:10,970
>> Aħwa huma xi li jkollhom
l-istess ġenitur, id-dritt?

666
00:36:10,970 --> 00:36:13,470
Huma qed fuq l-istess livell hawn.

667
00:36:13,470 --> 00:36:16,960
U mbagħad, kif kien
qal, tfal huma biss

668
00:36:16,960 --> 00:36:22,630
dak kollu li huwa pass wieħed taħt
l-node in kwistjoni, OK?

669
00:36:22,630 --> 00:36:23,470
Kessaħ.

670
00:36:23,470 --> 00:36:25,610
Allura siġra binarju.

671
00:36:25,610 --> 00:36:31,450
Jista 'xi ħadd periklu raden fuq waħda mill
il-karatteristiċi tas-siġra binarju?

672
00:36:31,450 --> 00:36:32,770
>> UDJENZA: Max żewġ werqiet.

673
00:36:32,770 --> 00:36:33,478
>> SPEAKER 1: Dritt.

674
00:36:33,478 --> 00:36:34,640
Allura max ta 'żewġ werqiet.

675
00:36:34,640 --> 00:36:39,730
Allura f'dan il-wieħed qabel, kellna dan wieħed
li kellhom tlieta, iżda fil-siġra binarju,

676
00:36:39,730 --> 00:36:45,000
għandek max ta 'żewġ
tfal għal kull ġenitur, id-dritt?

677
00:36:45,000 --> 00:36:46,970
Hemm ieħor
karatteristika interessanti.

678
00:36:46,970 --> 00:36:51,550
Ħadd ma jaf li?

679
00:36:51,550 --> 00:36:52,620
Siġra binarju.

680
00:36:52,620 --> 00:37:00,350
>> Allura siġra binarju se jkollhom kollox
fuq the-- dan huwa wieħed mhux sorted--

681
00:37:00,350 --> 00:37:05,320
iżda fil-siġra binarju magħżula,
kollox fuq il-lemin

682
00:37:05,320 --> 00:37:08,530
huwa akbar mill-ġenitur,
u kollox fuq ix-xellug

683
00:37:08,530 --> 00:37:10,035
huwa inqas mill-ġenitur.

684
00:37:10,035 --> 00:37:15,690
U li kien kwizz
kwistjoni qabel, hekk tajjeb li tkun taf.

685
00:37:15,690 --> 00:37:19,500
Allura l-mod kif aħna jiddefinixxu dan,
għal darb'oħra, għandna node ieħor.

686
00:37:19,500 --> 00:37:21,880
Dan jidher simili ħafna għal dak?

687
00:37:21,880 --> 00:37:28,336

688
00:37:28,336 --> 00:37:28,836
Doppjament

689
00:37:28,836 --> 00:37:29,320
>> Udjenza: Marbuta listi

690
00:37:29,320 --> 00:37:31,100
>> SPEAKER 1: Lista marbuta doppja, id-dritt?

691
00:37:31,100 --> 00:37:33,690
Hekk jekk aħna nissostitiwxxu din
ma preċedenti u li jmiss,

692
00:37:33,690 --> 00:37:35,670
dan ikun lista marbuta doppjament.

693
00:37:35,670 --> 00:37:40,125
Iżda f'dan il-każ, aħna fil-fatt
jkollhom xellug u lemin u li hu.

694
00:37:40,125 --> 00:37:41,500
Inkella, huwa eżattament l-istess.

695
00:37:41,500 --> 00:37:43,374
Aħna xorta jkollhom l-element
inti qed tfittex,

696
00:37:43,374 --> 00:37:45,988
u inti biss għandek żewġ pointers
ser ikun x'ikun jmiss.

697
00:37:45,988 --> 00:37:49,210

698
00:37:49,210 --> 00:37:51,870
Yeah, siġra tfittxija hekk binarju.

699
00:37:51,870 --> 00:37:57,665
Jekk aħna Avviż, kollox fuq il-
dritt hawnhekk hija than-- akbar

700
00:37:57,665 --> 00:37:59,850
jew kollox immedjatament
lejn il-lemin hawn

701
00:37:59,850 --> 00:38:02,840
huwa akbar minn, dak kollu
hawnhekk huwa inqas minn.

702
00:38:02,840 --> 00:38:06,980

703
00:38:06,980 --> 00:38:14,000
>> Hekk jekk konna biex tfittex permezz, dan
għandha tfittex qrib ħafna tfittxija binarju

704
00:38:14,000 --> 00:38:14,910
hawn, id-dritt?

705
00:38:14,910 --> 00:38:17,640
Ħlief minflok tfittex
fuq nofs il-firxa,

706
00:38:17,640 --> 00:38:21,720
aħna qed biss tħares lejn jew ix-xellug
ġenb jew il-lemin tas-siġra.

707
00:38:21,720 --> 00:38:24,850
Hekk jiġrilha ftit aktar sempliċi, I think.

708
00:38:24,850 --> 00:38:29,300
>> Hekk jekk għerq tiegħek huwa NULL,
ovvjament huwa biss falza.

709
00:38:29,300 --> 00:38:33,470
U jekk huwa hemmhekk, ovvjament huwa veru.

710
00:38:33,470 --> 00:38:35,320
Jekk huwa inqas minn, aħna tfittxija ix-xellug.

711
00:38:35,320 --> 00:38:37,070
Jekk huwa akbar minn,
aħna tfittxija fuq il-lemin.

712
00:38:37,070 --> 00:38:39,890
Huwa eżattament bħall tfittxija binarja,
biss struttura differenti data

713
00:38:39,890 --> 00:38:40,600
li aħna qed jużaw.

714
00:38:40,600 --> 00:38:42,790
Minflok firxa,
huwa biss siġra binarju.

715
00:38:42,790 --> 00:38:45,820

716
00:38:45,820 --> 00:38:48,090
>> OK, stacks.

717
00:38:48,090 --> 00:38:51,550
U wkoll, jidher qisu aħna
jista 'jkollhom xi ftit ta' żmien.

718
00:38:51,550 --> 00:38:54,460
Jekk nagħmlu, jien kuntent li jmorru
fuq kwalunkwe ta 'dan mill-ġdid.

719
00:38:54,460 --> 00:38:56,856
OK, hekk stacks.

720
00:38:56,856 --> 00:39:02,695
Hawn xi ħadd ftakar dak stacks--
kwalunkwe karatteristika ta 'ċumnija?

721
00:39:02,695 --> 00:39:05,550

722
00:39:05,550 --> 00:39:10,400
>> OK, hekk ħafna minna, I think,
jieklu fil-dining halls--

723
00:39:10,400 --> 00:39:13,100
kemm aħna ma tista 'tixtieq li.

724
00:39:13,100 --> 00:39:16,900
Imma ovvjament, inti tista 'taħseb ta' munzell
litteralment biss bħala munzell ta 'dixxijiet

725
00:39:16,900 --> 00:39:18,460
jew munzell ta 'affarijiet.

726
00:39:18,460 --> 00:39:21,820
U x'hemm importanti
li tirrealizza hija li huwa

727
00:39:21,820 --> 00:39:26,850
something-- il-karatteristika
li aħna sejħa hija by-- huwa LIFO.

728
00:39:26,850 --> 00:39:28,450
Hawn xi ħadd jaf liema li stands għall?

729
00:39:28,450 --> 00:39:29,070
Mmhmm?

730
00:39:29,070 --> 00:39:30,650
>> UDJENZA: L-aħħar fl-ewwel out.

731
00:39:30,650 --> 00:39:32,250
>> SPEAKER 1: Dritt, l-aħħar fl-ewwel out.

732
00:39:32,250 --> 00:39:36,585
Hekk jekk nafu, jekk aħna qed istivar affarijiet
up, l-eħfef ħaġa li grab off--

733
00:39:36,585 --> 00:39:39,570
u forsi l-unika ħaġa li nistgħu grab
off jekk munzell tagħna huwa enough-- big

734
00:39:39,570 --> 00:39:40,850
huwa dak l-element top.

735
00:39:40,850 --> 00:39:43,460
Sabiex ikun x'ikun tpoġġa fuq
last-- kif naraw hawn,

736
00:39:43,460 --> 00:39:46,370
ikun x'ikun kien imbuttat
fuq l-aktar recently-- huwa

737
00:39:46,370 --> 00:39:51,160
se tkun l-ewwel
ħaġa li aħna pop off, OK?

738
00:39:51,160 --> 00:39:56,324
>> Allura dak li għandna hawnhekk huwa
Struct typedef ieħor.

739
00:39:56,324 --> 00:39:58,740
Dan huwa verament biss bħal
crash kors fl-istruttura tad-data,

740
00:39:58,740 --> 00:40:01,650
hekk hemm ħafna jintefgħu fil int guys.

741
00:40:01,650 --> 00:40:02,540
I know.

742
00:40:02,540 --> 00:40:04,970
Allura għadhom Struct ieħor.

743
00:40:04,970 --> 00:40:06,740
Yay għal strutturi.

744
00:40:06,740 --> 00:40:16,660
>> U f'dan il-każ, huwa xi pointer
għal firxa li għandha xi kapaċità.

745
00:40:16,660 --> 00:40:20,830
Allura dan jirrappreżenta munzell tagħna
hawn, bħal firxa attwali tagħna

746
00:40:20,830 --> 00:40:22,520
thats azjenda elementi tagħna.

747
00:40:22,520 --> 00:40:24,850
U allura hawnhekk għandna xi daqs.

748
00:40:24,850 --> 00:40:31,170
>> U tipikament, inti tixtieq li żżomm
rekord ta 'kemm hu kbir munzell tiegħek huwa

749
00:40:31,170 --> 00:40:36,180
għaliex dak li għaddej biex jippermettu
inti tagħmel hija jekk inti taf l-daqs,

750
00:40:36,180 --> 00:40:39,170
din tippermetti li inti tgħid,
OK, I am fil-kapaċità?

751
00:40:39,170 --> 00:40:40,570
Nista żid xejn aktar?

752
00:40:40,570 --> 00:40:44,650
U wkoll jgħidlek
fejn il-quċċata tal-munzell tiegħek

753
00:40:44,650 --> 00:40:48,180
huwa sabiex inti tkun taf dak li inti
jistgħu attwalment tluq.

754
00:40:48,180 --> 00:40:51,760
U li fil-fatt se
jkun ftit aktar ċara hawn.

755
00:40:51,760 --> 00:40:57,350
>> Allura għal push, ħaġa waħda, jekk inti
kienu qatt biex jimplimentaw timbotta,

756
00:40:57,350 --> 00:41:01,330
kif I kien biss qal, tiegħek
munzell għandu daqs limitat, id-dritt?

757
00:41:01,330 --> 00:41:03,990
Firxa tagħna kellhom xi kapaċità.

758
00:41:03,990 --> 00:41:04,910
Huwa ta 'firxa.

759
00:41:04,910 --> 00:41:08,930
Huwa daqs fiss, għalhekk għandna bżonn li
kun żgur li aħna mhux qed tqegħid aktar

760
00:41:08,930 --> 00:41:11,950
fis firxa tagħna minn aħna
attwalment ikollhom spazju għall.

761
00:41:11,950 --> 00:41:16,900
>> Allura meta int ħolqien push
funzjoni, l-ewwel ħaġa li għandek tagħmel hu ngħidu aħna, OK,

762
00:41:16,900 --> 00:41:18,570
għandi spazju fil munzell tiegħi?

763
00:41:18,570 --> 00:41:23,330
Għaliex jekk jien ma, sorry,
I ma jista 'jaħżen element tiegħek.

764
00:41:23,330 --> 00:41:28,980
Jekk I do, imbagħad inti tixtieq li taħżen
huwa fil-quċċata tal-munzell, id-dritt?

765
00:41:28,980 --> 00:41:31,325
>> U dan huwa għaliex għandna
li jżommu rekord ta 'daqs tagħna.

766
00:41:31,325 --> 00:41:35,290
Jekk aħna ma jżommu rekord ta 'daqs tagħna,
ma nafux fejn li tqiegħed lilha.

767
00:41:35,290 --> 00:41:39,035
Aħna ma nafx kif ħafna affarijiet
huma fil-firxa tagħna diġà.

768
00:41:39,035 --> 00:41:41,410
Bħal ovvjament hemm modi
li forsi inti tista 'tagħmel dan.

769
00:41:41,410 --> 00:41:44,610
Inti tista initialize kollox biex NULL
u mbagħad tiċċekkja għall-aħħar NULL,

770
00:41:44,610 --> 00:41:47,950
imma ħaġa ferm aktar faċli huwa biss
ngħid, OK, jżommu rekord ta 'daqs.

771
00:41:47,950 --> 00:41:51,840
Like I know I jkollhom erba 'elementi
fil-firxa tiegħi, sabiex il-ħaġa li jmiss

772
00:41:51,840 --> 00:41:55,930
li nitfgħu fuq, aħna qed
ser taħżen bl-indiċi 4.

773
00:41:55,930 --> 00:42:00,940
U allura, ovvjament, dan ifisser li
inti stajt imbuttat b'suċċess xi ħaġa

774
00:42:00,940 --> 00:42:03,320
fuq munzell tiegħek, inti
tixtieq li jiżdied id-daqs

775
00:42:03,320 --> 00:42:08,880
sabiex tkun taf fejn inti hekk
li inti tista timbotta aktar affarijiet fuq.

776
00:42:08,880 --> 00:42:12,730
>> Hekk jekk aħna qed jippruvaw pop
xi ħaġa off-munzell,

777
00:42:12,730 --> 00:42:16,072
x'jista 'jkun l-ewwel ħaġa
li aħna rridu li jikkontrolla għal?

778
00:42:16,072 --> 00:42:18,030
Inti qed tipprova tieħu
xi ħaġa off munzell tiegħek.

779
00:42:18,030 --> 00:42:21,710

780
00:42:21,710 --> 00:42:24,781
Inti żgur hemm
xi ħaġa fil munzell tiegħek?

781
00:42:24,781 --> 00:42:25,280
No

782
00:42:25,280 --> 00:42:26,894
Allura dak li jista rridu li jivverifika?

783
00:42:26,894 --> 00:42:27,810
>> UDJENZA: [inaudible].

784
00:42:27,810 --> 00:42:29,880
SPEAKER 1: Iċċekkja għad-daqs?

785
00:42:29,880 --> 00:42:31,840
Daqs.

786
00:42:31,840 --> 00:42:38,520
Hekk irridu tikkontrolla biex tara jekk
Daqs tagħna huwa akbar minn 0, OK?

787
00:42:38,520 --> 00:42:44,970
U jekk huwa, allura aħna rridu li jonqos
Daqs tagħna ta '0 u ritorn dak.

788
00:42:44,970 --> 00:42:45,840
Għaliex?

789
00:42:45,840 --> 00:42:49,950
>> Fl-ewwel waħda konna
imbuttar, aħna imbuttat dan

790
00:42:49,950 --> 00:42:52,460
fuq id-daqs u d-daqs mbagħad aġġornati.

791
00:42:52,460 --> 00:42:57,850
F'dan il-każ, aħna qed decrementing daqs
u mbagħad tieħu off, qlugħ

792
00:42:57,850 --> 00:42:58,952
minn firxa tagħna.

793
00:42:58,952 --> 00:42:59,826
Għaliex jista nagħmlu dan?

794
00:42:59,826 --> 00:43:04,800

795
00:43:04,800 --> 00:43:11,811
Mela jekk ikolli ħaġa waħda fuq munzell tiegħi,
dak li jkun daqs tiegħi f'dak il-punt?

796
00:43:11,811 --> 00:43:13,140
1.

797
00:43:13,140 --> 00:43:15,180
>> U fejn tkun element 1 maħżuna?

798
00:43:15,180 --> 00:43:17,621
Fuq liema indiċi?

799
00:43:17,621 --> 00:43:18,120
UDJENZA: 0.

800
00:43:18,120 --> 00:43:19,060
SPEAKER 1: 0.

801
00:43:19,060 --> 00:43:22,800
Allura f'dan il-każ, aħna
dejjem bżonn tagħmel sure--

802
00:43:22,800 --> 00:43:27,630
minflok jirritornaw
daqs minus 1, għaliex aħna

803
00:43:27,630 --> 00:43:31,730
jafu li l-element tagħna huwa
ser jiġi maħżun fl-1 inqas

804
00:43:31,730 --> 00:43:34,705
irrispettivament mid-daqs tagħna huwa, dan
biss jieħu kura ta 'dan.

805
00:43:34,705 --> 00:43:36,080
Huwa mod ftit aktar eleganti.

806
00:43:36,080 --> 00:43:41,220
U aħna biss decrement tagħna
daqs u mbagħad daqs jirritornaw.

807
00:43:41,220 --> 00:43:42,330
Mmhmm?

808
00:43:42,330 --> 00:43:45,300
>> UDJENZA: I raden biss b'mod ġenerali,
għaliex kieku din l-istruttura tad-data

809
00:43:45,300 --> 00:43:47,800
tkun ta 'benefiċċju?

810
00:43:47,800 --> 00:43:50,660
>> SPEAKER 1: Hija tiddependi fuq il-kuntest tiegħek.

811
00:43:50,660 --> 00:43:57,420
Allura għal xi wħud mill-teorija,
jekk inti qed jaħdmu with-- OK,

812
00:43:57,420 --> 00:44:02,750
let me ara jekk ikun hemm wieħed benefiċċju
li huwa ta 'benefiċċju għal aktar minn barra

813
00:44:02,750 --> 00:44:05,420
ta 'CS.

814
00:44:05,420 --> 00:44:15,780
Bil stacks, kwalunkwe ħin għandek bżonn
li jżommu rekord ta 'xi ħaġa li

815
00:44:15,780 --> 00:44:20,456
huwa l-aktar reċentement miżjud huwa meta
int ser jridu jużaw munzell.

816
00:44:20,456 --> 00:44:24,770
>> U ma nistax think ta 'tajba
Eżempju ta 'dan id-dritt issa.

817
00:44:24,770 --> 00:44:29,955
Imma kull darba li l-aktar reċenti
ħaġa hija aktar importanti għalik,

818
00:44:29,955 --> 00:44:31,705
li meta munzell
se tkun utli.

819
00:44:31,705 --> 00:44:35,797

820
00:44:35,797 --> 00:44:39,330
Jien jippruvaw biex jaħsbu jekk
hemm waħda tajba għal dan.

821
00:44:39,330 --> 00:44:43,720
Jekk I think ta 'eżempju tajjeb fil-li jmiss
20 minuta, I definittivament se jgħidlek.

822
00:44:43,720 --> 00:44:49,455
>> Iżda b'mod ġenerali, jekk hemm xi ħaġa,
bħal I said aktar, fejn l-aktar reċenti

823
00:44:49,455 --> 00:44:52,470
huwa l-aktar importanti, thats
fejn munzell tidħol fis-play.

824
00:44:52,470 --> 00:44:58,860
Billi kjuwijiet huma tip ta 'l-oppost.

825
00:44:58,860 --> 00:44:59,870
U l-klieb ftit.

826
00:44:59,870 --> 00:45:00,890
Huwa ma 'dan kbira, id-dritt?

827
00:45:00,890 --> 00:45:03,299
Inħoss bħal I għandhom
biss ikollhom video bunny

828
00:45:03,299 --> 00:45:05,090
lemin fin-nofs ta '
taqsima għalik guys

829
00:45:05,090 --> 00:45:08,870
minħabba li din hija sezzjoni intensa.

830
00:45:08,870 --> 00:45:10,480
>> Hekk kju.

831
00:45:10,480 --> 00:45:12,710
Bażikament kju huwa bħal linja.

832
00:45:12,710 --> 00:45:15,780
You guys jien użu ċert li din ta 'kuljum,
eżatt bħal fil swali dining tagħna.

833
00:45:15,780 --> 00:45:18,160
Allura aħna għandna biex tmur fil-
u jiksbu trejs tagħna, jien

834
00:45:18,160 --> 00:45:21,260
żgur inti għandek tistenna fil-linja
swipe jew tikseb l-ikel tiegħek.

835
00:45:21,260 --> 00:45:24,650
>> Allura l-differenza hawn
hija li dan huwa FIFO.

836
00:45:24,650 --> 00:45:30,090
Hekk jekk LIFO kienet l-aħħar fl-ewwel
out, FIFO huwa l-ewwel fl-ewwel out.

837
00:45:30,090 --> 00:45:33,400
Allura dan huwa fejn kwalunkwe inti tpoġġi
fuq l-ewwel huwa tiegħek aktar importanti.

838
00:45:33,400 --> 00:45:35,540
Mela jekk inti kienu qed jistennew
fil line-- tista 'inti

839
00:45:35,540 --> 00:45:39,130
jimmaġina jekk inti marru biex
mur jiksbu l-iPhone ġodda

840
00:45:39,130 --> 00:45:42,800
u kien munzell fejn il-
aħħar persuna fil-linja ltqajna ewwel,

841
00:45:42,800 --> 00:45:44,160
nies se joqtlu lil xulxin.

842
00:45:44,160 --> 00:45:49,800
>> Allura FIFO, aħna qed kollha familjari ħafna
mal fid-dinja reali hawnhekk,

843
00:45:49,800 --> 00:45:54,930
u dan kollu għandu ma 'attwalment
tip ta 'recreating din il-linja kollu

844
00:45:54,930 --> 00:45:56,900
u queuing istruttura.

845
00:45:56,900 --> 00:46:02,390
Allura billi mal-munzell,
għandna push u pop.

846
00:46:02,390 --> 00:46:06,440
Bil-kju, għandna
enqueue u dequeue.

847
00:46:06,440 --> 00:46:10,910
Allura enqueue bażikament ifisser
poġġih fuq id-dahar,

848
00:46:10,910 --> 00:46:13,680
u mezzi dequeue tieħu
off minn quddiem.

849
00:46:13,680 --> 00:46:18,680
Allura istruttura tad-data tagħna huwa
ftit aktar ikkumplikata.

850
00:46:18,680 --> 00:46:21,060
Għandna t-tieni ħaġa li jżommu rekord ta.

851
00:46:21,060 --> 00:46:25,950
>> Allura mingħajr ir-ras, din
huwa eżattament munzell, id-dritt?

852
00:46:25,950 --> 00:46:27,900
Dan huwa l-istess struttura bħal munzell.

853
00:46:27,900 --> 00:46:32,480
L-unika ħaġa differenti issa hija aħna
jkollhom dan il-kap, li x'taħseb

854
00:46:32,480 --> 00:46:34,272
se jżommu rekord ta '?

855
00:46:34,272 --> 00:46:35,510
>> UDJENZA: L-ewwel wieħed.

856
00:46:35,510 --> 00:46:38,685
>> SPEAKER 1: Dritt, il-
ewwel ħaġa li nitfgħu fl.

857
00:46:38,685 --> 00:46:41,130
Il-kap tal-kju tagħna.

858
00:46:41,130 --> 00:46:42,240
Kulmin huwa l-ewwel fil-linja.

859
00:46:42,240 --> 00:46:45,300

860
00:46:45,300 --> 00:46:49,420
Kull dritt, hekk jekk nagħmlu enqueue.

861
00:46:49,420 --> 00:46:52,720

862
00:46:52,720 --> 00:46:55,920
Għal darb'oħra, ma 'xi
dawn l-istrutturi tad-data,

863
00:46:55,920 --> 00:46:59,760
peress li aħna qed jittrattaw ma 'firxa,
għandna bżonn li jiċċekkja jekk ikollna spazju.

864
00:46:59,760 --> 00:47:03,290
>> Dan huwa tip simili me javżak
inti guys, jekk inti tiftaħ fajl,

865
00:47:03,290 --> 00:47:04,760
għandek bżonn sabiex jikkontrolla għal null.

866
00:47:04,760 --> 00:47:08,330
Ma 'kwalunkwe minn dawn stacks
u kjuwijiet, inti għandek bżonn

867
00:47:08,330 --> 00:47:13,420
biex tara jekk hemm spazju għax aħna qed
jittrattaw ma 'firxa daqs fiss,

868
00:47:13,420 --> 00:47:16,030
kif naraw here-- 0, 1 kollha sa 5.

869
00:47:16,030 --> 00:47:20,690
Allura dak li nagħmlu fil-każ hija verifika
biex tara jekk aħna xorta jkollhom spazju.

870
00:47:20,690 --> 00:47:23,110
Huwa d-daqs tagħna inqas minn kapaċità?

871
00:47:23,110 --> 00:47:28,480
>> Jekk iva, għandna bżonn li jaħżinha bir
il-denb u aħna aġġornament daqs tagħna.

872
00:47:28,480 --> 00:47:30,250
Allura dak li jista 'jkun l-denb f'dan il-każ?

873
00:47:30,250 --> 00:47:32,360
Mhuwiex espliċitament miktub.

874
00:47:32,360 --> 00:47:33,380
Kif aħna taħżen dan?

875
00:47:33,380 --> 00:47:34,928
Liema jkun l-denb tkun?

876
00:47:34,928 --> 00:47:38,600

877
00:47:38,600 --> 00:47:40,190
>> Mela ejja jimxu permezz ta dan l-eżempju.

878
00:47:40,190 --> 00:47:44,590
Allura dan huwa firxa ta 'daqs 6, id-dritt?

879
00:47:44,590 --> 00:47:49,220
U għandna d-dritt issa, id-daqs tagħna hija ta '5.

880
00:47:49,220 --> 00:47:55,240
U meta aħna poġġih fil, li għaddej
li jmorru fil-ħames indiċi, id-dritt?

881
00:47:55,240 --> 00:47:57,030
Allura jaħżen fil denb.

882
00:47:57,030 --> 00:48:05,600
>> Mod ieħor biex jiktbu denb kien biss
jkun array tagħna fuq indiċi tad-daqs, id-dritt?

883
00:48:05,600 --> 00:48:07,560
Dan huwa d-daqs 5.

884
00:48:07,560 --> 00:48:11,490
Ħaġa li jmiss se jmorru fil-5.

885
00:48:11,490 --> 00:48:12,296
Kessaħ?

886
00:48:12,296 --> 00:48:13,290
OK.

887
00:48:13,290 --> 00:48:16,350
Jiġrilha ftit aktar kumplikata
meta nibdew messing mal-kap.

888
00:48:16,350 --> 00:48:17,060
Iva?

889
00:48:17,060 --> 00:48:20,090
>> UDJENZA: Dan ifisser li aħna
kien iddikjara firxa li

890
00:48:20,090 --> 00:48:23,880
kien ta 'ħames elementi twil u
allura aħna qed żżid fuq dan?

891
00:48:23,880 --> 00:48:24,730
>> SPEAKER 1: No

892
00:48:24,730 --> 00:48:27,560
Allura f'dan il-każ, dan huwa munzell.

893
00:48:27,560 --> 00:48:31,760
Dan ikun dikjarat
bħala firxa ta 'daqs 6.

894
00:48:31,760 --> 00:48:37,120
U f'dan il-każ, aħna
biss ikollhom spazju wieħed xellug.

895
00:48:37,120 --> 00:48:42,720
>> OK, hekk ħaġa waħda hija f'din
każ, jekk ewlieni tagħna huwa ta '0,

896
00:48:42,720 --> 00:48:45,270
allura aħna biss tista 'żżid fil-daqs.

897
00:48:45,270 --> 00:48:51,020
Iżda jiġrilha ftit delikati
għaliex fil-fatt, huma

898
00:48:51,020 --> 00:48:52,840
ma jkollhomx slide
għal dan, hekk jien ser

899
00:48:52,840 --> 00:48:56,670
tiġbed waħda għaliex mhuwiex
pjuttost li sempliċi ladarba inti

900
00:48:56,670 --> 00:48:59,230
tibda jwarrbu ta 'affarijiet.

901
00:48:59,230 --> 00:49:03,920
Allura billi ma munzell
inti biss qatt

902
00:49:03,920 --> 00:49:08,920
biex joqogħdu jinkwetaw dwar dak id-daqs huwa
meta int żżid xi ħaġa fuq,

903
00:49:08,920 --> 00:49:15,710
bil kju għandek bżonn ukoll li tagħmel
żgur li l-kap tiegħek hi ġġustifikata,

904
00:49:15,710 --> 00:49:20,760
għaliex ħaġa jibred dwar kjuwijiet
hija li jekk int ma fil-kapaċità,

905
00:49:20,760 --> 00:49:23,040
inti tista 'attwalment jagħmilha around.

906
00:49:23,040 --> 00:49:28,810
>> OK, hekk wieħed thing-- oh,
dan huwa ġibs terribbli.

907
00:49:28,810 --> 00:49:31,815
Ħaġa waħda li wieħed għandu jikkonsidra huwa l-każ.

908
00:49:31,815 --> 00:49:35,514

909
00:49:35,514 --> 00:49:37,140
Aħna ser biss tagħmel ħamsa.

910
00:49:37,140 --> 00:49:41,810
OK, hekk aħna qed tmur biex
jiġifieri l-ras hija hawnhekk.

911
00:49:41,810 --> 00:49:46,140
Dan huwa ta '0, 1, 2, 3, 4.

912
00:49:46,140 --> 00:49:54,210
>> Il-kap hemm, u
jekk jogħġbok jkollhom affarijiet fihom.

913
00:49:54,210 --> 00:49:58,340
U rridu li żżid xi ħaġa fil, id-dritt?

914
00:49:58,340 --> 00:50:01,170
Allura l-ħaġa li għandna bżonn li
jafu hu li l-kap huwa dejjem

915
00:50:01,170 --> 00:50:05,620
ser jiċċaqalqu b'dan il-mod u
imbagħad loop lura madwar, OK?

916
00:50:05,620 --> 00:50:10,190
>> Allura dan kju għandha l-ispazju, id-dritt?

917
00:50:10,190 --> 00:50:13,950
Hija għandha spazju fil-bidu nett,
tip ta 'l-oppost ta' dan.

918
00:50:13,950 --> 00:50:17,920
Allura dak li għandna bżonn tagħmel hu li aħna
bżonn jikkalkulaw il-denb.

919
00:50:17,920 --> 00:50:20,530
Jekk taf li tiegħek
ras ma mxietx, denb

920
00:50:20,530 --> 00:50:24,630
huwa biss array tiegħek
l-indiċi tad-daqs.

921
00:50:24,630 --> 00:50:30,000
>> Iżda fir-realtà, jekk inti qed tuża kju,
kap tiegħek huwa probabbilment qed tiġi aġġornata.

922
00:50:30,000 --> 00:50:33,890
Allura dak li għandek bżonn tagħmel huwa
attwalment tikkalkula l-denb.

923
00:50:33,890 --> 00:50:39,990
Allura dak li nagħmlu hu din il-formula
hawn, li jien ser tavżak

924
00:50:39,990 --> 00:50:42,680
guys jaħsbu dwar, u
allura aħna ser nitkellmu dwar dan.

925
00:50:42,680 --> 00:50:49,567

926
00:50:49,567 --> 00:50:50,400
Allura dan huwa kapaċità.

927
00:50:50,400 --> 00:50:55,890

928
00:50:55,890 --> 00:50:59,660
>> Allura dan se attwalment
jagħtuk mod biex tagħmel dan.

929
00:50:59,660 --> 00:51:03,205

930
00:51:03,205 --> 00:51:04,330
Għaliex f'dan il-każ, liema?

931
00:51:04,330 --> 00:51:09,205
Ewlieni tagħna huwa fl-1, id-daqs tagħna huwa ta '4.

932
00:51:09,205 --> 00:51:11,760

933
00:51:11,760 --> 00:51:18,490
Jekk aħna MOD dik b'5, aħna nikseb 0,
li huwa fejn għandna input.

934
00:51:18,490 --> 00:51:23,320

935
00:51:23,320 --> 00:51:26,080
>> Hekk allura fil-każ li jmiss,
jekk konna biex jagħmlu dan,

936
00:51:26,080 --> 00:51:33,390
ngħidu, OK, ejja dequeue xi ħaġa.

937
00:51:33,390 --> 00:51:34,390
Aħna dequeue dan.

938
00:51:34,390 --> 00:51:37,740
Nieħdu out dan l-element, id-dritt?

939
00:51:37,740 --> 00:51:47,930
>> U issa ras tagħna hija li tipponta hawn,
u aħna tixtieq iżżid fil ħaġa oħra.

940
00:51:47,930 --> 00:51:52,470
Dan huwa bażikament l-
dahar tal-linja tagħna, id-dritt?

941
00:51:52,470 --> 00:51:55,450
Kjuwijiet tista wrap madwar il-firxa.

942
00:51:55,450 --> 00:51:57,310
Din kienet waħda mir-differenzi ewlenin.

943
00:51:57,310 --> 00:51:58,780
Stacks, inti ma tistax tagħmel dan.

944
00:51:58,780 --> 00:52:01,140
>> Bil kjuwijiet, inti tista
minħabba li l-kwistjonijiet

945
00:52:01,140 --> 00:52:03,940
hija li inti taf liema
ġie miżjud l-aktar reċentement.

946
00:52:03,940 --> 00:52:10,650
Peress li kollox se jiġi miżjud fil-
id-direzzjoni leftward, f'dan il-każ,

947
00:52:10,650 --> 00:52:16,480
u mbagħad wrap madwar, inti tista '
tkompli tqegħid fl-elementi ġodda

948
00:52:16,480 --> 00:52:18,830
fuq quddiem tal-firxa
għaliex mhuwiex verament

949
00:52:18,830 --> 00:52:20,640
quddiem tal-firxa jibqgħalu.

950
00:52:20,640 --> 00:52:26,320
Inti tista 'taħseb l-bidu tal-
array fejn ras tiegħek fil-fatt hu.

951
00:52:26,320 --> 00:52:29,710
>> Allura din il-formula huwa kif
inti tikkalkula denb tiegħek.

952
00:52:29,710 --> 00:52:32,780

953
00:52:32,780 --> 00:52:35,610
Does li jagħmel sens?

954
00:52:35,610 --> 00:52:36,110
OK.

955
00:52:36,110 --> 00:52:39,400

956
00:52:39,400 --> 00:52:44,040
OK, dequeue, u mbagħad
inti guys jkollhom 10 minuti

957
00:52:44,040 --> 00:52:48,840
li jistaqsu lili xi mistoqsijiet li tiċċara
trid, għaliex naf huwa crazy.

958
00:52:48,840 --> 00:52:51,980
>> Kull dritt, hekk fl-istess way--
I do not know jekk inti guys ndunat,

959
00:52:51,980 --> 00:52:53,450
iżda CS hija kollha dwar ix-xejriet.

960
00:52:53,450 --> 00:52:57,370
Affarijiet huma pjuttost l-
istess, biss ma tweaks ċkejkna.

961
00:52:57,370 --> 00:52:58,950
Allura istess ħaġa hawn.

962
00:52:58,950 --> 00:53:04,040
Għandna bżonn biex tikkontrolla biex tara jekk aħna fil-fatt
ikollhom xi ħaġa fil-kju tagħna, id-dritt?

963
00:53:04,040 --> 00:53:05,960
Say, OK, huwa d-daqs tagħna akbar minn 0?

964
00:53:05,960 --> 00:53:06,730
Kessaħ.

965
00:53:06,730 --> 00:53:10,690
>> Jekk nagħmlu, allura nimxu ras tagħna, li
huwa dak I biss murija hawn.

966
00:53:10,690 --> 00:53:13,870
Aħna aġġornament ras tagħna tkun waħda aktar.

967
00:53:13,870 --> 00:53:18,390
U allura aħna decrement tagħna
daqs u jirritorna l-element.

968
00:53:18,390 --> 00:53:21,000

969
00:53:21,000 --> 00:53:26,250
>> Hemm ħafna aktar konkret
kodiċi fuq study.cs50.net,

970
00:53:26,250 --> 00:53:29,440
u I jirrakkomanda ħafna li jmorru
permezz ta 'dan jekk ikollok ħin,

971
00:53:29,440 --> 00:53:30,980
anki jekk huwa biss a-kodiċi psewdo.

972
00:53:30,980 --> 00:53:35,980
U jekk inti guys trid titkellem permezz
li miegħi waħda fuq waħda, jekk jogħġbok let me

973
00:53:35,980 --> 00:53:37,500
jafu.

974
00:53:37,500 --> 00:53:38,770
I d jkunu kuntenti li.

975
00:53:38,770 --> 00:53:42,720
Strutturi ta 'dejta, jekk
tieħu CS 124, inti ser

976
00:53:42,720 --> 00:53:47,830
jafu li l-istrutturi tad-data jiksbu ħafna
gost u dan huwa biss bidu.

977
00:53:47,830 --> 00:53:50,350
>> So I know huwa diffiċli.

978
00:53:50,350 --> 00:53:51,300
Huwa OK.

979
00:53:51,300 --> 00:53:52,410
Aħna jissieltu.

980
00:53:52,410 --> 00:53:53,630
I still do.

981
00:53:53,630 --> 00:53:56,660
Sabiex ma joqogħdu jinkwetaw wisq dwar dan.

982
00:53:56,660 --> 00:54:02,390
>> Iżda li hija bażikament tiegħek
crash kors fl-istrutturi tad-data.

983
00:54:02,390 --> 00:54:03,400
Naf huwa ħafna.

984
00:54:03,400 --> 00:54:06,860
Hemm xi ħaġa li aħna
tixtieq li tmur aktar mill-ġdid?

985
00:54:06,860 --> 00:54:09,400
Xejn rridu nitkellmu permezz?

986
00:54:09,400 --> 00:54:10,060
Iva?

987
00:54:10,060 --> 00:54:16,525
>> UDJENZA: Għal dak eżempju, hekk
il-denb ġdida hija ta '0 fuq dak?

988
00:54:16,525 --> 00:54:17,150
SPEAKER 1: Iva.

989
00:54:17,150 --> 00:54:18,230
UDJENZA: OK.

990
00:54:18,230 --> 00:54:24,220
Mela allura għaddejjin,
youd għandek 1 plus 4 or--

991
00:54:24,220 --> 00:54:27,671
>> SPEAKER 1: Allura inti kienu jgħidu,
meta irridu imorru tagħmel dan mill-ġdid?

992
00:54:27,671 --> 00:54:28,296
UDJENZA: Yeah.

993
00:54:28,296 --> 00:54:38,290
Mela jekk inti kienu jidhru out-- fejn huma
inti kalkolu tal-denb minn fil-li?

994
00:54:38,290 --> 00:54:44,260
>> SPEAKER 1: Allura l-denb
kien in-- I mibdula din.

995
00:54:44,260 --> 00:54:52,010
Allura f'dan l-eżempju hawn, dan kien
l-array aħna qed tħares lejn, OK?

996
00:54:52,010 --> 00:54:54,670
Allura aħna għandna affarijiet fil-1, 2, 3, u 4.

997
00:54:54,670 --> 00:55:05,850
Allura aħna għandna ewlieni tagħna huwa ugwali għal 1 fil-
dan il-punt, u d-daqs tagħna huwa ugwali għal 4

998
00:55:05,850 --> 00:55:07,050
f'dan il-punt, id-dritt?

999
00:55:07,050 --> 00:55:08,960
>> Inti kollha jaqblu li huwa l-każ?

1000
00:55:08,960 --> 00:55:14,620
Allura nagħmlu l-kap plus-daqs, li
jagħtina 5, u allura aħna Mod b'5.

1001
00:55:14,620 --> 00:55:20,690
Nikbru 0, li tgħidilna li huwa 0
fejn huwa denb tagħna, fejn għandna l-ispazju.

1002
00:55:20,690 --> 00:55:22,010
>> UDJENZA: X'hemm għatu?

1003
00:55:22,010 --> 00:55:23,520
>> SPEAKER 1: Il-kapaċità.

1004
00:55:23,520 --> 00:55:24,020
Jiddispjacini.

1005
00:55:24,020 --> 00:55:29,640
Allura li huwa d-daqs ta 'firxa tiegħek.

1006
00:55:29,640 --> 00:55:35,210

1007
00:55:35,210 --> 00:55:36,047
Iva?

1008
00:55:36,047 --> 00:55:39,210
>> UDJENZA: [inaudible] qabel
nerġgħu lura l-element?

1009
00:55:39,210 --> 00:55:46,270
>> SPEAKER 1: Allura aħna nimxu l-
ras jew jirritornaw il-mument?

1010
00:55:46,270 --> 00:55:52,680
Hekk jekk nimxu wieħed, decrement-daqs?

1011
00:55:52,680 --> 00:55:54,150
Żomm fuq.

1012
00:55:54,150 --> 00:55:55,770
I definitely nesa ieħor.

1013
00:55:55,770 --> 00:56:00,646

1014
00:56:00,646 --> 00:56:01,990
Qatt f'moħħhom.

1015
00:56:01,990 --> 00:56:04,980
Ma jkunx hemm formula ieħor.

1016
00:56:04,980 --> 00:56:09,980
Yeah, inti tixtieq li jirritornaw
ir-ras u mbagħad jimxu lura.

1017
00:56:09,980 --> 00:56:13,270
>> UDJENZA: OK, għaliex Fuq dan
punt, il-kap kien ta '0,

1018
00:56:13,270 --> 00:56:18,452
u allura inti tixtieq li jirritornaw
indiċi 0 u mbagħad jagħmlu ras 1?

1019
00:56:18,452 --> 00:56:19,870
>> SPEAKER 1: Dritt.

1020
00:56:19,870 --> 00:56:22,820
Naħseb li hemm ieħor
formula tip ta 'bħal dan.

1021
00:56:22,820 --> 00:56:26,970
I ma jkollhomx dan fuq il-quċċata tar-ras tiegħi bħala
Ma rridx li jtik l-waħda ħażina.

1022
00:56:26,970 --> 00:56:35,470
Imma naħseb li huwa perfettament valida biex
jiġifieri, OK, taħżen din element-- x'ikun

1023
00:56:35,470 --> 00:56:40,759
element ras is-- decrement tiegħek
daqs, jimxu ras tiegħek fuq, u r-ritorn

1024
00:56:40,759 --> 00:56:41,800
kwalunkwe li element huwa.

1025
00:56:41,800 --> 00:56:44,760
C'est perfettament valida.

1026
00:56:44,760 --> 00:56:45,260
OK.

1027
00:56:45,260 --> 00:56:48,360

1028
00:56:48,360 --> 00:56:53,560
Inħoss bħal dan mhuwiex
bħall-most-- int ma

1029
00:56:53,560 --> 00:56:55,740
ser jimxu minn hawn
simili, iva, naf jipprova.

1030
00:56:55,740 --> 00:56:56,880
I ltqajna kollha.

1031
00:56:56,880 --> 00:56:57,670
C'est OK.

1032
00:56:57,670 --> 00:57:00,200
I wegħda.

1033
00:57:00,200 --> 00:57:05,240
Imma l-istrutturi tad-data huma xi ħaġa li
hija tieħu ħafna ħin biex jidraw.

1034
00:57:05,240 --> 00:57:10,010
Probabilment waħda mill-agħar
affarijiet, I think, fil-kors.

1035
00:57:10,010 --> 00:57:15,330
>> Allura huwa definittivament tieħu
ripetizzjoni u tfittex at-- I

1036
00:57:15,330 --> 00:57:20,050
ma verament jafu listi marbuta
sal I għamilt bogħod wisq magħhom,

1037
00:57:20,050 --> 00:57:22,550
bl-istess mod li għamilt ma
verament jifhem pointers

1038
00:57:22,550 --> 00:57:27,040
sal I kellna biex jgħallmu għal żewġ
snin u tagħmel psets tiegħi stess magħha.

1039
00:57:27,040 --> 00:57:28,990
Huwa jieħu ħafna ta 'tennija u l-ħin.

1040
00:57:28,990 --> 00:57:32,600
U eventwalment, se tip ta 'ikklikkja.

1041
00:57:32,600 --> 00:57:36,320
>> Iżda fil-frattemp, jekk għandek tip
ta 'fehim livell għoli ta' liema

1042
00:57:36,320 --> 00:57:39,321
dawn jagħmlu, punti favur
u cons-- li huwa dak

1043
00:57:39,321 --> 00:57:41,820
aħna verament tendenza li jenfasizzaw,
speċjalment fil-kors intro.

1044
00:57:41,820 --> 00:57:45,511
Bħal, għaliex kieku nużaw
jipprova fuq firxa?

1045
00:57:45,511 --> 00:57:48,010
Bħal, liema huma l-pożittivi
u negattivi ta 'kull wieħed minn dawk?

1046
00:57:48,010 --> 00:57:51,610
>> U jifhmu l-kompromessi
bejn kull wieħed minn dawn l-istrutturi

1047
00:57:51,610 --> 00:57:54,910
huwa dak ħafna aktar importanti dritt issa.

1048
00:57:54,910 --> 00:57:58,140
Jista 'jkun hemm wieħed crazy
kwistjoni jew tnejn li l-

1049
00:57:58,140 --> 00:58:03,710
ser jgħidlek biex jimplimentaw push jew
jimplimentaw pop jew enqueue u dequeue.

1050
00:58:03,710 --> 00:58:07,340
Iżda għall-parti l-kbira, li dak
fehim livell ogħla u aktar

1051
00:58:07,340 --> 00:58:09,710
ta 'ħakma intuwittivi huwa
aktar importanti milli fil-fatt

1052
00:58:09,710 --> 00:58:11,250
jkunu jistgħu jimplimentawha.

1053
00:58:11,250 --> 00:58:14,880
>> Huwa d jkun verament tal-biża jekk lilkom kollha
tista 'tmur out u jmorru jimplimentaw jipprova,

1054
00:58:14,880 --> 00:58:19,720
iżda aħna nifhmu mhuwiex neċessarjament
l-aktar ħaġa raġonevoli dritt issa.

1055
00:58:19,720 --> 00:58:23,370
Imma inti tista 'fil pset tiegħek, jekk inti tixtieq
għal, u allura inti ser tingħata prattika,

1056
00:58:23,370 --> 00:58:27,200
u mbagħad forsi inti taf
verament jifhmu dan.

1057
00:58:27,200 --> 00:58:27,940
Iva?

1058
00:58:27,940 --> 00:58:30,440
>> UDJENZA: OK, iva, liema huma
aħna maħsuba biex jużaw fil-pset?

1059
00:58:30,440 --> 00:58:31,916
Do I bżonn tuża wieħed minnhom?

1060
00:58:31,916 --> 00:58:32,540
SPEAKER 1: Iva.

1061
00:58:32,540 --> 00:58:34,199
Hekk ikollok l-għażla tiegħek.

1062
00:58:34,199 --> 00:58:36,740
I raden f'dan il-każ, nistgħu
jitkellmu dwar il-pset ftit

1063
00:58:36,740 --> 00:58:40,480
minħabba I dam permezz ta 'dawn.

1064
00:58:40,480 --> 00:58:47,779
Hekk fil pset tiegħek, inti għandek tiegħek
għażla ta 'tipprova jew tabelli hash.

1065
00:58:47,779 --> 00:58:49,570
Xi nies se jippruvaw
u jintużaw filtri blanzun,

1066
00:58:49,570 --> 00:58:51,840
iżda dawk teknikament mhumiex korretti.

1067
00:58:51,840 --> 00:58:55,804
Minħabba n-natura probabilistic tagħhom,
dawn jagħtu pożittivi foloz kultant.

1068
00:58:55,804 --> 00:58:57,095
Huma qed tfittex jibred fi, għalkemm.

1069
00:58:57,095 --> 00:58:59,030
Jirrakkomanda ħafna tfittex
lejn lilhom mill-inqas.

1070
00:58:59,030 --> 00:59:03,260
Imma għandek l-għażla tiegħek
bejn tabella hash u jipprova.

1071
00:59:03,260 --> 00:59:06,660
U li għaddej biex jkun fejn
inti tagħbija fil tiegħek dizzjunarju.

1072
00:59:06,660 --> 00:59:09,230
>> U ikollok bzonn li jagħżlu
funzjoni hash tiegħek,

1073
00:59:09,230 --> 00:59:13,420
ikollok bzonn li jagħżlu kif ħafna
Bramel għandek, u se jvarjaw.

1074
00:59:13,420 --> 00:59:17,440
Bħal jekk għandek aktar bramel,
forsi inneħħu run aktar mgħaġġla.

1075
00:59:17,440 --> 00:59:22,790
Imma forsi int wasting
lott ta 'spazju li mod, għalkemm.

1076
00:59:22,790 --> 00:59:26,320
Int għandek figura hija out.

1077
00:59:26,320 --> 00:59:27,140
Mmhmm?

1078
00:59:27,140 --> 00:59:29,875
>> UDJENZA: Inti qal qabel li
nistgħu nużaw funzjonijiet oħra hash,

1079
00:59:29,875 --> 00:59:31,750
li aħna ma jkollhom
toħloq funzjoni hash?

1080
00:59:31,750 --> 00:59:32,666
>> SPEAKER 1: Iva, id-dritt.

1081
00:59:32,666 --> 00:59:38,150
Allura litteralment għall-funzjoni hash tiegħek,
bħal google "funzjoni hash"

1082
00:59:38,150 --> 00:59:40,770
u tfittex xi dawk jibred.

1083
00:59:40,770 --> 00:59:43,250
Inti mhux mistennija li jibnu
funzjonijiet hash tiegħek stess.

1084
00:59:43,250 --> 00:59:46,100
Nies iqattgħu tagħhom
teżijiet fuq dawn l-affarijiet.

1085
00:59:46,100 --> 00:59:50,250
>> Allura ma joqogħdu jinkwetaw dwar il-bini tiegħek stess.

1086
00:59:50,250 --> 00:59:53,350
Isibu waħda online biex tibda bil.

1087
00:59:53,350 --> 00:59:56,120
Xi wħud minnhom inti għandek
jimmanipulaw ftit

1088
00:59:56,120 --> 00:59:59,430
biex jagħmlu tipi ritorn żgur jaqblu
u whatnot, hekk fil-bidu,

1089
00:59:59,430 --> 01:00:02,420
I jirrakkomanda jużaw xi ħaġa
verament faċli li forsi ftit

1090
01:00:02,420 --> 01:00:04,680
hashes fuq l-ewwel ittra.

1091
01:00:04,680 --> 01:00:08,760
U mbagħad darba inti għandek li xogħol,
jinkorporaw funzjoni hash cooler.

1092
01:00:08,760 --> 01:00:09,260
Mmhmm?

1093
01:00:09,260 --> 01:00:13,020
>> UDJENZA: Would jipprova jkun jew
effiċjenti iżda biss diffiċli biex, like--

1094
01:00:13,020 --> 01:00:15,880
>> SPEAKER 1: Allura jipprova, I think,
huwa intuwittivament diffiċli biex jiġu implimentati

1095
01:00:15,880 --> 01:00:18,310
iżda huwa mgħaġġel ħafna.

1096
01:00:18,310 --> 01:00:20,620
Madankollu, jieħu aktar spazju.

1097
01:00:20,620 --> 01:00:25,270
Għal darb'oħra, inti tista jottimizzaw kemm ta 'dawk fil-
modi differenti u hemm modi to--

1098
01:00:25,270 --> 01:00:26,770
UDJENZA: Kif aħna gradat fuq dan?

1099
01:00:26,770 --> 01:00:27,540
Ma matter--

1100
01:00:27,540 --> 01:00:29,164
>> SPEAKER 1: Allura inti qed gradati mod normali.

1101
01:00:29,164 --> 01:00:31,330
Inti qed tmur biex jiġi ggradat fuq disinn.

1102
01:00:31,330 --> 01:00:36,020
Liema mod inti tagħmel, inti tixtieq li
kun ċert li huwa kif eleganti kemm jista 'jkun

1103
01:00:36,020 --> 01:00:38,610
u effiċjenti kemm jista 'jkun.

1104
01:00:38,610 --> 01:00:41,950
Imma jekk inti tagħżel jipprova jew hash
tabella, sakemm taħdem,

1105
01:00:41,950 --> 01:00:45,350
aħna kuntenti ma 'dak.

1106
01:00:45,350 --> 01:00:48,370
U jekk inti tuża xi ħaġa li hashes
fuq l-ewwel ittra, li l-multa,

1107
01:00:48,370 --> 01:00:51,410
bħal forsi bħall-disinn għaqli.

1108
01:00:51,410 --> 01:00:53,410
Aħna wkoll qed jilħaq il-
punt f'dan semester--

1109
01:00:53,410 --> 01:00:55,340
I do not know jekk inti
guys noticed-- jekk int

1110
01:00:55,340 --> 01:00:58,780
gradi pset jonqsu ftit
minħabba d-disinn u whatnot,

1111
01:00:58,780 --> 01:00:59,900
li perfettament multa.

1112
01:00:59,900 --> 01:01:02,960
Huwa jkollna sa punt fejn tiegħek
programmi huma jkollna aktar ikkumplikata.

1113
01:01:02,960 --> 01:01:04,830
Hemm aktar postijiet
inti tista 'ttejjeb fuq.

1114
01:01:04,830 --> 01:01:06,370
>> Allura huwa perfettament normali.

1115
01:01:06,370 --> 01:01:08,810
Mhuwiex li int
tagħmel agħar fuq pset tiegħek.

1116
01:01:08,810 --> 01:01:11,885
Huwa biss aħna qed qed diffiċli fuqek issa.

1117
01:01:11,885 --> 01:01:13,732
Allura kulħadd tħossok.

1118
01:01:13,732 --> 01:01:14,940
I biss gradati psets kollha tiegħek.

1119
01:01:14,940 --> 01:01:16,490
Naf kulħadd qed tħossok.

1120
01:01:16,490 --> 01:01:19,600
>> Allura ma tkun inkwetat dwar dan.

1121
01:01:19,600 --> 01:01:23,580
U jekk għandek xi mistoqsijiet dwar
psets qabel jew modi inti tista 'ttejjeb,

1122
01:01:23,580 --> 01:01:27,760
I jippruvaw u jikkummentaw il speċifika
postijiet, imma xi kultant huwa tard

1123
01:01:27,760 --> 01:01:30,840
u niġi għajjien.

1124
01:01:30,840 --> 01:01:34,885
Hemm xi affarijiet oħra
dwar strutturi ta 'dejta?

1125
01:01:34,885 --> 01:01:37,510
Jien ċert li inti guys ma verament
trid titkellem dwarhom aktar,

1126
01:01:37,510 --> 01:01:42,650
imma jekk ikun hemm, jien kuntent li
jmorru fuqhom, kif ukoll xi ħaġa

1127
01:01:42,650 --> 01:01:45,580
minn lecture dan passat
ġimgħa jew ġimgħa li għaddiet.

1128
01:01:45,580 --> 01:01:51,580
>> Naf aħħar ġimgħa kienet kollha ta 'reviżjoni, hekk
aħna jista 'jkollhom skipped fuq xi reviżjoni

1129
01:01:51,580 --> 01:01:54,190
minn lecture.

1130
01:01:54,190 --> 01:01:58,230
Kwalunkwe mistoqsijiet oħra I jistgħu jwieġbu?

1131
01:01:58,230 --> 01:01:59,350
OK, id-dritt.

1132
01:01:59,350 --> 01:02:02,400
Ukoll, inti guys toħroġ 15 minuta kmieni.

1133
01:02:02,400 --> 01:02:08,370
>> Nispera li din kienet semi-utli għall-inqas,
u jien se tara inti guys ġimgħa d-dieħla,

1134
01:02:08,370 --> 01:02:12,150
jew ħinijiet tal-uffiċċju Ħamis.

1135
01:02:12,150 --> 01:02:15,285
Hemm talbiet għal snacks
għall-ġimgħa d-dieħla, huwa l-ħaġa?

1136
01:02:15,285 --> 01:02:17,459
Minħabba I nesa kandju illum.

1137
01:02:17,459 --> 01:02:19,750
U I miġjuba kandju aħħar
ġimgħa, iżda kienet Jum Columbus,

1138
01:02:19,750 --> 01:02:25,400
għaldaqstant kien hemm bħal sitt persuni li
kellu erba 'boroż ta' kandju lilhom infushom.

1139
01:02:25,400 --> 01:02:28,820
I tista 'ġġib starbursts
ġdid jekk inti tixtieq.

1140
01:02:28,820 --> 01:02:29,580
Starbursts?

1141
01:02:29,580 --> 01:02:32,250
OK, ħsejjes tajba.

1142
01:02:32,250 --> 01:02:35,050
Have jum kbir, guys.

1143
01:02:35,050 --> 01:02:39,510