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[Music kucheza]

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SPIKA 1: All haki.

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Kila mtu kuwakaribisha nyuma na sehemu ya.

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Natumaini wote ni mafanikio
zinalipwa kutoka Jaribio yako

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kutoka wiki iliyopita.

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Najua ni kidogo mambo mara kwa mara.

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Kama nilivyosema hapo kabla, kama wewe ni
ndani ya kupotoka standard,

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si kweli wasiwasi kuhusu hilo, hasa
kwa sehemu chini ya starehe.

11
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Hiyo ni kuhusu ambapo unapaswa kuwa.

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>> Kama alifanya kubwa, basi kutisha.

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Kudos na wewe.

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Na kama wewe kujisikia kama unahitaji
kidogo msaada zaidi, tafadhali

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kujisikia huru na kufikia
kufanyika kwa yoyote ya TFS.

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Sisi sote tuko hapa kusaidia.

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>> Hiyo ni kwa nini sisi kufundisha.

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Hiyo ni kwa nini mimi niko hapa kila Jumatatu kwa ajili yenu
wavulana na katika ofisi masaa juu ya Alhamisi.

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Hivyo tafadhali jisikie huru basi mimi kujua
kama wewe ni wasiwasi kuhusu kitu chochote

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au kama kuna kitu chochote juu ya jaribio
kwamba Ningependa kwa kweli kama kushughulikia.

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>> Hivyo ajenda ya leo ni
wote kuhusu miundo ya data.

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Baadhi ya hizi ni kwenda tu kuwa tu
kupata wewe familiarized na haya.

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Unaweza milele kutekeleza
nao katika darasa hili.

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Baadhi yao wewe,
kama kwa Speller yako pset.

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>> Itabidi uchaguzi wako
kati ya meza hash na anajaribu.

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Hivyo tutaweza dhahiri kuwa kwenda juu ya wale.

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Ni kwenda kuwa dhahiri zaidi ya aina
ya kiwango cha juu cha kifungu leo, ingawa,

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kwa sababu kuna mengi ya yao, na kama
sisi akaenda katika maelezo ya utekelezaji

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juu ya yote haya, sisi hakutaka
hata kupata njia ya orodha wanaohusishwa

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na labda kidogo ya meza hash.

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>> Hivyo kuzaa na mimi.

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Sisi siyo kwenda kufanya
kama kiasi coding wakati huu.

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Kama una maswali yoyote kuhusu hilo
au unataka kuona kutekelezwa

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au kujaribu mwenyewe,
Mimi dhahiri kupendekeza

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kwenda study.cs50.net, ambayo
ina mifano ya yote haya.

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Ni itabidi PowerPoints yangu
pamoja na maelezo kwamba sisi

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huwa na kutumia kama vile baadhi ya programu
mazoezi, hasa kwa ajili ya mambo

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kama orodha wanaohusishwa na binary
miti mwingi na cues.

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Ngazi ya juu zaidi hivyo kidogo, ambayo
inaweza kuwa nzuri kwa ajili ya guys.

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>> Hivyo, pamoja na kwamba, tutaweza kupata kuanza.

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Na pia, yes-- Quizzes.

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Nadhani wengi wenu walio katika
Sehemu yangu na Quizzes yako,

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lakini mtu akija katika au sababu baadhi yenu
kufanya hivyo, wao ni haki hapa mbele.

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>> Hivyo wanaohusishwa orodha.

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Najua aina hii ya unaendelea
nyuma kabla ya jaribio yako.

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Hiyo ilikuwa wiki moja kabla ya
kwamba sisi kujifunza kuhusu hili.

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Lakini katika kesi hii, tutaweza tu
kwenda kidogo zaidi kwa kina.

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>> Hivyo kwa nini huenda sisi kuchagua
wanaohusishwa orodha juu ya safu?

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Nini tofauti kati yao?

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Ndiyo?

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>> Watazamaji: Unaweza kupanua wanaohusishwa
orodha dhidi safu ya fasta ukubwa.

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SPIKA 1: Haki.

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safu ina ambapo fasta ukubwa
orodha wanaohusishwa ina ukubwa kutofautiana.

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Hivyo kama sisi hawajui jinsi
kiasi tunataka kuhifadhi,

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orodha wanaohusishwa inatupa kubwa
njia ya kufanya kwamba kwa sababu tunaweza tu

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kuongeza juu ya nodi mwingine na kuongeza juu
mwingine nodi na kuongeza juu ya nodi mwingine.

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Lakini nini inaweza kuwa biashara-off?

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Je, mtu yeyote kumbuka biashara-off
kati ya arrays na orodha wanaohusishwa?

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Mmhmm?

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>> Watazamaji: Una
kwenda kwa njia ya njia yote

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kupitia orodha wanaohusishwa
kupata kipengele katika orodha.

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Katika safu, unaweza
tu kupata kipengele.

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>> SPIKA 1: Haki.

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Hivyo pamoja na arrays--

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>> Watazamaji: [inaudible].

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>> SPIKA 1: Kwa arrays, tuna
kile kinachoitwa upatikanaji random.

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Ina maana kwamba kama tunataka nini ni
milele hatua ya tano ya orodha

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au uhakika wa tano wa wetu
safu, tunaweza tu kunyakua hiyo.

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Kama ni orodha wanaohusishwa, tuna
iterate kupitia, haki?

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Hivyo kupata kipengele katika
safu ni muda mara kwa mara,

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ambapo pamoja na orodha wanaohusishwa ingekuwa
zaidi uwezekano kuwa wakati linear kwa sababu labda

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kipengele yetu ni njia yote mwishoni.

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Tuna kutafuta njia ya kila kitu.

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Hivyo, pamoja na data zote hizi
miundo tunakwenda

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kwa kutumia muda zaidi kidogo juu ya,
kile ni pluses na hasi.

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Wakati wanaweza tunataka
kutumia moja juu ya nyingine?

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Na hiyo ni aina ya
Jambo kubwa ya kuchukua mbali.

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>> Hivyo tuna hapa
ufafanuzi wa nodi.

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Ni kama moja ya kipengele katika
orodha yetu wanaohusishwa, haki?

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Hivyo sisi ni wote ukoo
na typedef structs yetu,

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ambayo sisi akaenda juu katika mapitio mara ya mwisho.

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Ilikuwa kimsingi kujenga tu
aina nyingine data kwamba tunaweza kutumia.

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>> Na katika kesi hii, ni baadhi ya nodi
kwamba itafanya baadhi integer katika.

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Na kisha nini sehemu ya pili hapa?

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Mtu yeyote?

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>> Watazamaji: [inaudible].

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>> SPIKA 1: Yeah.

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Ni pointer nodi ijayo.

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Hivyo hii lazima kweli kuwa juu hapa.

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Hii ni pointer ya aina
nodi kwa jambo la pili.

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Na kwamba ni nini wao
amewazunguka nodi zetu.

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Baridi.

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>> Haki wote, hivyo pamoja na kutafuta, kama tulikuwa
kusema tu kabla ya mkono, kama wewe ni

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kwenda kutafuta njia,
una kweli iterate

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kupitia orodha yako wanaohusishwa.

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Hivyo kama sisi ni kuangalia kwa idadi
9, tunataka kuanza saa kichwa wetu

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na kwamba pointi sisi mwanzoni
ya orodha yetu wanaohusishwa, haki?

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Na sisi kusema, sawa, hana huu
nodi vyenye namba 9?

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Hakuna?

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>> Haki zote, kwenda moja ijayo.

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Kuifuata.

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Je vyenye namba 9?

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Hakuna

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Kufuata moja ijayo.

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>> Hivyo tuna kweli iterate
kupitia orodha yetu wanaohusishwa.

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Hatuwezi tu kwenda moja kwa moja ambapo 9 ni.

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Na kama wewe guys kweli wanataka
kuona baadhi kuna Pseudo-kificho up.

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Tuna baadhi ya kazi ya utafutaji hapa
kwamba inachukua in-- nini kuchukua katika?

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Unafikiri nini?

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Hivyo ni rahisi moja.

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Hii ni nini?

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Watazamaji: [inaudible].

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SPIKA 1: idadi sisi ni kuangalia kwa.

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Haki?

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Na nini itakuwa hii yanahusiana na?

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Ni pointer?

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>> Watazamaji: nodi.

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>> SPIKA 1: nodi kwa orodha
kwamba sisi ni kuangalia, haki?

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Hivyo tuna baadhi nodes ni pointer hapa.

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Hii ni hatua ambayo inaenda
kweli iterate kupitia orodha yetu.

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Sisi kuweka sawa kuorodhesha
sababu tu kwamba

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kuiandaa sawa na
kuanza ya orodha yetu wanaohusishwa.

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>> Na wakati ni si null, wakati
bado tuna mambo katika orodha yetu,

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kuangalia kuona kama kwamba nodi ina
idadi sisi ni kuangalia kwa.

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Kurudi kweli.

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Vinginevyo, update, haki?

129
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>> Kama ni null, sisi exit yetu
kitanzi wakati na kurudi uongo

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kwa sababu hiyo ina maana sisi si kupatikana.

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Je, kila mtu kupata jinsi ya kuwa kazi?

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OK.

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

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>> Hivyo, pamoja na kuingizwa, wewe
wana njia tatu tofauti.

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Unaweza prepend, unaweza append
na unaweza kuingiza katika assorted.

136
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Katika kesi hiyo, sisi ni
kwenda kufanya prepend.

137
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Je, mtu yeyote kujua jinsi wale
kesi tatu wanaweza kutofautiana?

138
00:06:33,380 --> 00:06:36,920
>> Hivyo prepend ina maana kwamba kuweka
ni mbele ya orodha yako.

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Hivyo kwamba itakuwa na maana kwamba hakuna jambo
nini nodi yako, hakuna jambo

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nini thamani ni, wewe ni kwenda
kuiweka haki hapa mbele, sawa?

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Ni kwenda kuwa ya kwanza
kipengele katika orodha yako.

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>> Kama append yake, ni kwenda
kwenda nyuma ya orodha yako.

143
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Na kuingiza ndani ya assorted maana wewe ni
kwenda kuweka kweli katika nafasi

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ambapo ni kuvaa orodha yako wanaohusishwa yamepangwa.

145
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Tena, jinsi ya kutumia
wale na wakati matumizi

146
00:07:00,810 --> 00:07:02,530
yao hutegemea kesi yako.

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

148
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Kama haina haja ya
kutatuliwa, prepend inaelekea

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kuwa nini watu wengi
kutumia kwa sababu huna

150
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kwenda kupitia orodha nzima
kupata mwisho wa kuongeza juu, haki?

151
00:07:15,680 --> 00:07:17,720
Unaweza tu fimbo ni haki katika.

152
00:07:17,720 --> 00:07:21,930
>> Hivyo sisi kwenda kwa njia
insertion 1 hivi sasa.

153
00:07:21,930 --> 00:07:26,360
Jambo hivyo moja kwamba mimi nina kwenda
sana kupendekeza juu ya pset hii

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ni kuteka mambo ya nje, kama siku zote.

155
00:07:29,820 --> 00:07:35,130
Ni muhimu sana kwamba wewe update
kuyatumia yako katika mpangilio sahihi

156
00:07:35,130 --> 00:07:38,620
kwa sababu kama wewe update yao
kidogo nje ya utaratibu,

157
00:07:38,620 --> 00:07:42,210
wewe ni kwenda kuishia
kupoteza sehemu ya orodha yako.

158
00:07:42,210 --> 00:07:49,680
>> Hivyo kwa mfano, katika kesi hii, sisi ni
kuwaambia kichwa kwa uhakika tu 1.

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00:07:49,680 --> 00:07:56,070
Kama sisi tu kufanya hivyo
bila kuokoa hii 1,

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00:07:56,070 --> 00:07:58,570
hatuna wazo nini
1 lazima kumweka kwa sasa

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00:07:58,570 --> 00:08:02,490
kwa sababu tumekuwa waliopotea nini
kichwa alisema kwa.

162
00:08:02,490 --> 00:08:05,530
Hivyo jambo moja kukumbuka
wakati unafanya prepend

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00:08:05,530 --> 00:08:09,630
ni kuokoa kile
pointi kichwa kwanza,

164
00:08:09,630 --> 00:08:15,210
basi reassign yake, na kisha update
nini nodi yako mpya lazima kumweka kwa.

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

166
00:08:20,870 --> 00:08:22,560
Katika kesi hiyo, hii ni njia moja ya kufanya hivyo.

167
00:08:22,560 --> 00:08:25,440
>> Hivyo kama sisi alikuwa amefanya hivyo kwa njia hii
ambapo sisi tu reassigned kichwa,

168
00:08:25,440 --> 00:08:30,320
tunapoteza kimsingi wetu
orodha nzima, haki?

169
00:08:30,320 --> 00:08:38,000
Njia moja ya kufanya hivyo ni kuwa na 1 uhakika kwa
ijayo, na kisha kuwa na uhakika na kichwa 1.

170
00:08:38,000 --> 00:08:42,650
Au unaweza kufanya aina ya kama
kuhifadhi muda, ambayo mimi aliyesema kuhusu.

171
00:08:42,650 --> 00:08:45,670
>> Lakini reassigning yako
kuyatumia katika mpangilio sahihi

172
00:08:45,670 --> 00:08:48,750
ni kwenda kuwa sana, sana
muhimu kwa pset hii.

173
00:08:48,750 --> 00:08:53,140
Vinginevyo, wewe ni kwenda kuwa na hash
meza au kujaribu kuwa tu kwenda kuwa

174
00:08:53,140 --> 00:08:56,014
sehemu tu ya maneno kwamba
wanataka na kisha mmhmm you're--?

175
00:08:56,014 --> 00:08:58,930
Watazamaji: Nini muda
Jambo kuhifadhi wewe walikuwa wanazungumza juu?

176
00:08:58,930 --> 00:09:00,305
SPIKA 1: kuhifadhi muda.

177
00:09:00,305 --> 00:09:02,760
Hivyo kimsingi mwingine
njia unaweza kufanya hivyo

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ni kuhifadhi mkuu wa kitu, kama
kuhifadhi variable muda.

179
00:09:07,650 --> 00:09:11,250
Hawawajui kwa 1 na
kisha update 1 kwa uhakika

180
00:09:11,250 --> 00:09:13,830
kwa chochote kichwa kutumika kwa uhakika na.

181
00:09:13,830 --> 00:09:16,920
Njia hii ni wazi
zaidi ya kifahari kwa sababu wewe

182
00:09:16,920 --> 00:09:20,770
hawahitaji thamani ya muda mfupi, lakini
tu kutoa njia nyingine ya kufanya hivyo.

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

184
00:09:23,999 --> 00:09:25,790
Na sisi kweli kufanya kuwa
baadhi kificho kwa hili.

185
00:09:25,790 --> 00:09:28,080
Hivyo kwa orodha wanaohusishwa, sisi
kweli kuwa baadhi ya kanuni.

186
00:09:28,080 --> 00:09:31,930
Hivyo kuingiza hapa, hii ni prepending.

187
00:09:31,930 --> 00:09:34,290
Hivyo hii inaingia ni katika kichwa.

188
00:09:34,290 --> 00:09:38,820
>> Jambo hivyo kwanza, unahitaji
kujenga nodi yako mpya, bila shaka,

189
00:09:38,820 --> 00:09:40,790
na kuangalia kwa null.

190
00:09:40,790 --> 00:09:43,250
Daima ni nzuri.

191
00:09:43,250 --> 00:09:47,840
Na kisha unahitaji hawawajui maadili.

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00:09:47,840 --> 00:09:51,260
Kila wewe kujenga nodi mpya,
sijui nini ni akizungumzia ijayo,

193
00:09:51,260 --> 00:09:54,560
hivyo unataka initialize kwa null.

194
00:09:54,560 --> 00:09:58,760
Kama haina kuishia akizungumzia jambo
mwingine, anapata reassigned na ni faini.

195
00:09:58,760 --> 00:10:00,740
Kama ni jambo la kwanza ni
katika orodha, inahitaji

196
00:10:00,740 --> 00:10:04,270
kwa uhakika na kwa sababu null
hiyo ni mwisho wa orodha.

197
00:10:04,270 --> 00:10:12,410
>> Hivyo basi kwa kuingiza, tunaona hapa sisi
ni kumshirikisha thamani ya pili ya nodi wetu

198
00:10:12,410 --> 00:10:17,380
kuwa chochote kichwa ni,
ambayo ni nini tulikuwa hapa.

199
00:10:17,380 --> 00:10:19,930
Hiyo ni nini sisi tu alivyofanya.

200
00:10:19,930 --> 00:10:25,820
Na kisha sisi ni kumshirikisha kichwa kwa uhakika
nodi wetu mpya, kwa sababu kumbuka,

201
00:10:25,820 --> 00:10:31,090
mpya ni baadhi pointer nodi,
na kwamba ni nini hasa kichwa ni.

202
00:10:31,090 --> 00:10:34,370
Hiyo ni kwa nini hasa sisi
kuwa hii mshale accessor.

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

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

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

206
00:10:38,130 --> 00:10:41,100
>> Watazamaji: Je tuna
initialize mpya ijayo null kwanza,

207
00:10:41,100 --> 00:10:44,240
au tunaweza tu initialize kwa kichwa?

208
00:10:44,240 --> 00:10:48,210
>> SPIKA 1: Mpya ijayo
mahitaji ya kuwa NULL kuanza

209
00:10:48,210 --> 00:10:53,760
kwa sababu hamjui
ambapo ni kwenda kuwa.

210
00:10:53,760 --> 00:10:56,100
Pia, hii ni aina ya
tu kama dhana.

211
00:10:56,100 --> 00:10:59,900
Wewe kuweka sawa na NULL tu kufanya
kuhakikisha kwamba besi yako yote ni kufunikwa

212
00:10:59,900 --> 00:11:04,070
kabla ya kufanya reassignment yoyote ili
wewe ni daima uhakika kwamba itakuwa

213
00:11:04,070 --> 00:11:08,880
kuwa akizungumzia thamani maalum
dhidi kama thamani ya takataka.

214
00:11:08,880 --> 00:11:12,210
Kwa sababu, yeah, sisi hawawajui
mpya ijayo moja kwa moja,

215
00:11:12,210 --> 00:11:15,420
lakini ni zaidi kama
mazoezi mazuri kwa initialize

216
00:11:15,420 --> 00:11:19,270
katika njia hiyo na kisha reassign.

217
00:11:19,270 --> 00:11:23,420
>> OK, hivyo doubly wanaohusishwa orodha ya sasa.

218
00:11:23,420 --> 00:11:24,601
Tufanye nini kufikiri?

219
00:11:24,601 --> 00:11:26,350
Nini tofauti na
doubly wanaohusishwa orodha?

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

221
00:11:30,750 --> 00:11:34,300
>> Hivyo katika orodha yetu wanaohusishwa, tunaweza
tu hoja katika mwelekeo mmoja, haki?

222
00:11:34,300 --> 00:11:35,270
Sisi tu ijayo.

223
00:11:35,270 --> 00:11:36,760
Tunaweza tu kwenda mbele.

224
00:11:36,760 --> 00:11:40,300
>> Na orodha doubly wanaohusishwa,
sisi pia unaweza hoja nyuma.

225
00:11:40,300 --> 00:11:44,810
Hivyo tuna si tu
idadi hiyo tunataka kuhifadhi,

226
00:11:44,810 --> 00:11:50,110
tuna ambapo inaelekeza katika ijayo
na ambapo sisi tu alikuja kutoka.

227
00:11:50,110 --> 00:11:52,865
Hivyo hii inaruhusu kwa ajili ya
baadhi traversal bora.

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

229
00:11:56,620 --> 00:12:01,240
>> Nodes hivyo doubly wanaohusishwa,
sawa, haki?

230
00:12:01,240 --> 00:12:05,000
Tu tofauti ni sasa sisi
kuwa ijayo na uliopita.

231
00:12:05,000 --> 00:12:06,235
Ni tofauti tu.

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

233
00:12:09,570 --> 00:12:14,790
>> Hivyo kama sisi walikuwa prepend au append-- sisi
hawana kificho kwa hili hadi here--

234
00:12:14,790 --> 00:12:17,830
lakini kama ungekuwa kujaribu na
kuingiza, jambo muhimu

235
00:12:17,830 --> 00:12:19,980
ni haja ya kufanya
kuhakikisha wewe ni kumshirikisha

236
00:12:19,980 --> 00:12:23,360
wote uliopita wako na yako
pointer ijayo kwa usahihi.

237
00:12:23,360 --> 00:12:29,010
Hivyo katika kesi hii, wewe ungekuwa
si tu initialize ijayo,

238
00:12:29,010 --> 00:12:31,820
you initialize uliopita.

239
00:12:31,820 --> 00:12:36,960
Kama tuko katika kichwa cha orodha, sisi
itakuwa si tu kufanya kichwa sawa mpya,

240
00:12:36,960 --> 00:12:41,750
lakini mpya uliopita yetu lazima
uhakika na kichwa, haki?

241
00:12:41,750 --> 00:12:43,380
>> Hiyo ni tofauti tu.

242
00:12:43,380 --> 00:12:47,200
Na kama unataka zaidi mazoezi na
haya na orodha wanaohusishwa, na kuingiza,

243
00:12:47,200 --> 00:12:49,900
na kufuta, na kuingiza
katika orodha assorted,

244
00:12:49,900 --> 00:12:52,670
tafadhali angalia study.cs50.net.

245
00:12:52,670 --> 00:12:54,870
Kuna kundi la mazoezi kubwa.

246
00:12:54,870 --> 00:12:55,870
Mimi sana kupendekeza yao.

247
00:12:55,870 --> 00:12:59,210
Napenda tulikuwa na wakati wa kwenda kwa njia yao
lakini kuna mengi ya miundo data

248
00:12:59,210 --> 00:13:01,530
kupata njia.

249
00:13:01,530 --> 00:13:02,650
>> OK, hivyo meza hash.

250
00:13:02,650 --> 00:13:07,070
Hii pengine ni wengi
muhimu kidogo kwa pset yako

251
00:13:07,070 --> 00:13:11,090
hapa kwa sababu wewe ni kwenda kuwa
kutekeleza mmoja wa haya, au kujaribu.

252
00:13:11,090 --> 00:13:12,200
Mimi kwa kweli kama meza hash.

253
00:13:12,200 --> 00:13:13,110
Wao ni pretty cool.

254
00:13:13,110 --> 00:13:17,080
>> Hivyo kimsingi nini
kinachotokea ni meza hash

255
00:13:17,080 --> 00:13:22,050
ni wakati sisi kwa kweli wanahitaji haraka
insertion, kufutwa, na Luke.

256
00:13:22,050 --> 00:13:25,010
Hayo ni mambo ambayo sisi ni
kipaumbele katika meza hash.

257
00:13:25,010 --> 00:13:29,500
Wanaweza kupata pretty kubwa,
lakini kama tutaweza kuona na inajaribu,

258
00:13:29,500 --> 00:13:33,040
kuna mambo ambayo ni kubwa sana.

259
00:13:33,040 --> 00:13:38,330
>> Lakini kimsingi, hash wote
meza ni hash

260
00:13:38,330 --> 00:13:47,215
kwamba anasema ambayo ndoo kuweka kila
ya data yako, kila mmoja wa mambo yako katika.

261
00:13:47,215 --> 00:13:51,140
njia rahisi kufikiri ya meza hash
ni kwamba ni ndoo tu ya mambo,

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

263
00:13:51,770 --> 00:13:59,720
Hivyo wakati wewe ni kuchagua mambo kwa
kama barua ya kwanza ya jina yao,

264
00:13:59,720 --> 00:14:01,820
hiyo ni aina ya kama meza hash.

265
00:14:01,820 --> 00:14:06,180
>> Hivyo kama mimi walikuwa na kundi guys ni
katika makundi ya yeyote jina la kuanza

266
00:14:06,180 --> 00:14:11,670
na zaidi ya hapa, au mtu siku ya kuzaliwa
ni katika Januari, Februari, Machi,

267
00:14:11,670 --> 00:14:15,220
chochote, kwamba ni ufanisi
kujenga meza hash.

268
00:14:15,220 --> 00:14:18,120
Ni kujenga tu ndoo kwamba
you kutatua mambo yako katika

269
00:14:18,120 --> 00:14:19,520
ili uweze kupata yao rahisi zaidi.

270
00:14:19,520 --> 00:14:22,300
Hivyo njia hii wakati mimi haja
kupata moja ya wewe,

271
00:14:22,300 --> 00:14:24,680
Sina kutafuta
njia ya kila ya majina yako.

272
00:14:24,680 --> 00:14:29,490
Naweza kuwa kama, oh, najua kwamba
Danielle siku ya kuzaliwa ni in--

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

274
00:14:30,240 --> 00:14:30,948
SPIKA 1: Aprili.

275
00:14:30,948 --> 00:14:33,120
Hivyo mimi kuangalia mwezi Aprili yangu
ndoo, na kwa bahati yoyote,

276
00:14:33,120 --> 00:14:38,270
yeye itabidi kuwa moja tu huko na
muda wangu alikuwa mara kwa mara katika maana ya kwamba,

277
00:14:38,270 --> 00:14:41,230
ambapo kama mimi kuwa na kuangalia
kupitia rundo zima la watu,

278
00:14:41,230 --> 00:14:43,090
ni kwenda kuchukua muda mrefu zaidi.

279
00:14:43,090 --> 00:14:45,830
Hivyo meza hash ni kweli ndoo tu.

280
00:14:45,830 --> 00:14:48,630
Njia rahisi ya kufikiria yao.

281
00:14:48,630 --> 00:14:52,930
>> Hivyo jambo muhimu sana kuhusu
meza hash ni kazi hash.

282
00:14:52,930 --> 00:14:58,140
Hivyo mambo mimi tu kuongelea, kama
barua yako ya kwanza ya jina yako ya kwanza

283
00:14:58,140 --> 00:15:01,450
au siku yako ya kuzaliwa kwa mwezi,
haya ni mawazo kwamba

284
00:15:01,450 --> 00:15:03,070
kweli correlate kwa hash kazi.

285
00:15:03,070 --> 00:15:08,900
Ni njia tu ya kuamua ambayo
ndoo uko kipengele huenda katika, sawa?

286
00:15:08,900 --> 00:15:14,850
Hivyo kwa pset hii, unaweza kuangalia juu ya
pretty much yoyote ya kazi hash unataka.

287
00:15:14,850 --> 00:15:16,030
>> Haina kuwa yako mwenyewe.

288
00:15:16,030 --> 00:15:21,140
Kuna baadhi ya wale kweli baridi nje
pale kwamba kufanya kila aina ya mambo math.

289
00:15:21,140 --> 00:15:25,170
Na kama unataka kufanya yako
spellchecker super haraka,

290
00:15:25,170 --> 00:15:27,620
Napenda dhahiri
kuangalia katika moja ya hizo.

291
00:15:27,620 --> 00:15:32,390
>> Lakini pia kuna
rahisi ndio, kama compute

292
00:15:32,390 --> 00:15:39,010
Jumla ya maneno, kama
kila herufi ina idadi.

293
00:15:39,010 --> 00:15:39,940
Compute jibu.

294
00:15:39,940 --> 00:15:42,230
Kwamba huamua ndoo.

295
00:15:42,230 --> 00:15:45,430
Wao pia wana ndio rahisi kwamba
ni tu kama wote wa A hapa,

296
00:15:45,430 --> 00:15:47,050
yote ya B hapa.

297
00:15:47,050 --> 00:15:48,920
Yoyote mmoja wa wale.

298
00:15:48,920 --> 00:15:55,770
>> Kimsingi, ni tu anakwambia ambayo
safu ripoti kipengele yako lazima kwenda katika.

299
00:15:55,770 --> 00:15:58,690
Tu kuamua bucket--
ni wote hash kazi ni.

300
00:15:58,690 --> 00:16:04,180
Hivyo hapa tuna mfano ambayo ni
tu barua ya kwanza ya kamba

301
00:16:04,180 --> 00:16:05,900
kwamba nilikuwa tu kuzungumza juu.

302
00:16:05,900 --> 00:16:11,900
>> Hivyo una baadhi hash kwamba tu
barua ya kwanza ya kamba yako minus A,

303
00:16:11,900 --> 00:16:16,090
ambayo nitakupa baadhi
idadi kati ya 0 na 25.

304
00:16:16,090 --> 00:16:20,790
Na nini unataka kufanya ni
kuhakikisha kwamba hii inawakilisha

305
00:16:20,790 --> 00:16:24,110
ukubwa wa hash yako table--
jinsi ndoo wengi kuna.

306
00:16:24,110 --> 00:16:25,860
Na wengi wa hawa
kazi hash, wao ni

307
00:16:25,860 --> 00:16:31,630
kwenda kuwa kurudi maadili kwamba huenda
kuwa mbali juu idadi ya ndoo

308
00:16:31,630 --> 00:16:33,610
kwamba kwa kweli kuwa na
katika hash meza yako,

309
00:16:33,610 --> 00:16:37,240
hivyo unahitaji kufanya
uhakika na Mod na wale.

310
00:16:37,240 --> 00:16:42,190
Vinginevyo, ni kwenda kusema,
oh, ni lazima kuwa katika ndoo 5,000

311
00:16:42,190 --> 00:16:46,040
lakini wewe tu 30
ndoo katika hash meza yako.

312
00:16:46,040 --> 00:16:49,360
Na bila shaka, sisi wote tunajua kwamba ni
kwenda kusababisha baadhi ya makosa mambo.

313
00:16:49,360 --> 00:16:52,870
Ili kuhakikisha Mod na
ukubwa wa hash meza yako.

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

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

316
00:16:58,930 --> 00:17:00,506
Hivyo migongano.

317
00:17:00,506 --> 00:17:02,620
Ni kila mtu nzuri hadi sasa?

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

319
00:17:03,120 --> 00:17:05,900
>> Watazamaji: Kwa nini ni
kurudi thamani kama mkubwa?

320
00:17:05,900 --> 00:17:09,210
>> SPIKA 1: Kulingana na algorithm
kwamba hash kazi yako anatumia.

321
00:17:09,210 --> 00:17:12,270
Baadhi yao kufanya
mambo ya kuzidisha.

322
00:17:12,270 --> 00:17:16,270
Na ni wote kuhusu kupata
hata usambazaji,

323
00:17:16,270 --> 00:17:18,490
hivyo kufanya baadhi ya kweli
mambo mambo wakati mwingine.

324
00:17:18,490 --> 00:17:20,960
Hayo ni yote.

325
00:17:20,960 --> 00:17:22,140
Kitu kingine chochote?

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

327
00:17:22,829 --> 00:17:24,480
>> Hivyo migongano.

328
00:17:24,480 --> 00:17:29,270
Kimsingi, kama nilivyosema awali,
katika bora kesi,

329
00:17:29,270 --> 00:17:32,040
ndoo yoyote mimi kuangalia katika ni
kwenda na jambo moja,

330
00:17:32,040 --> 00:17:34,160
hivyo mimi si kuwa na kuangalia wakati wote, haki?

331
00:17:34,160 --> 00:17:37,040
Mimi aidha kujua ni huko au ni
si, na kwamba ni nini sisi kweli wanataka.

332
00:17:37,040 --> 00:17:43,960
Lakini kama tuna maelfu ya
pointi data na chini ya idadi hiyo

333
00:17:43,960 --> 00:17:48,700
ndoo, tunakwenda kuwa
collisions ambapo hatimaye kitu

334
00:17:48,700 --> 00:17:54,210
ni kwenda kuwa na kuishia katika
ndoo ambayo tayari ina kipengele.

335
00:17:54,210 --> 00:17:57,390
>> Hivyo swali ni, nini
sisi kufanya katika kesi hiyo?

336
00:17:57,390 --> 00:17:58,480
Tufanye nini?

337
00:17:58,480 --> 00:17:59,300
Sisi tayari kuwa na kitu huko?

338
00:17:59,300 --> 00:18:00,060
Je, sisi tu kutupa nje?

339
00:18:00,060 --> 00:18:00,700
>> Hakuna

340
00:18:00,700 --> 00:18:01,980
Tuna kuweka wote wawili.

341
00:18:01,980 --> 00:18:06,400
Hivyo njia kwamba sisi
kawaida kufanya hivyo ni nini?

342
00:18:06,400 --> 00:18:08,400
Ni muundo wa data kile
sisi tu kuongelea?

343
00:18:08,400 --> 00:18:09,316
Watazamaji: Wanaohusishwa orodha.

344
00:18:09,316 --> 00:18:10,500
SPIKA 1: orodha wanaohusishwa.

345
00:18:10,500 --> 00:18:16,640
Hivyo sasa, badala ya kila moja ya haya
ndoo tu kuwa moja ya kipengele,

346
00:18:16,640 --> 00:18:24,020
itakuja vyenye orodha wanaohusishwa ya
mambo ambayo walikuwa heshi ndani yake.

347
00:18:24,020 --> 00:18:27,588
OK, haina kila mtu aina ya kupata wazo kwamba?

348
00:18:27,588 --> 00:18:30,546
Sababu sisi hakuweza kuwa safu
kwa sababu hatujui mambo ngapi

349
00:18:30,546 --> 00:18:31,730
ni kwenda kuwa huko.

350
00:18:31,730 --> 00:18:36,540
orodha wanaohusishwa inaruhusu sisi
kuwa tu idadi halisi kwamba

351
00:18:36,540 --> 00:18:38,465
ni heshi ndani ya kwamba ndoo, haki?

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

353
00:18:42,260 --> 00:18:50,500
>> Hivyo linear udadisi ni
kimsingi idea-- hii

354
00:18:50,500 --> 00:18:52,300
ni moja ya njia ya kukabiliana na mgongano.

355
00:18:52,300 --> 00:18:58,010
Nini unaweza kufanya ni kama, katika hii
kesi, berry ilikuwa heshi ndani ya 1

356
00:18:58,010 --> 00:19:01,130
na tayari tuna
kitu pale, wewe tu

357
00:19:01,130 --> 00:19:04,840
kuendelea chini mpaka
kupata yanayopangwa tupu.

358
00:19:04,840 --> 00:19:06,370
Hiyo ni moja ya njia ya kushughulikia hilo.

359
00:19:06,370 --> 00:19:09,020
njia nyingine ya kushughulikia
ni pamoja na kile sisi tu

360
00:19:09,020 --> 00:19:12,280
called-- wanaohusishwa
orodha inaitwa chaining.

361
00:19:12,280 --> 00:19:20,510
>> Hivyo wazo hii kazi kama
hash meza yako unafikiri

362
00:19:20,510 --> 00:19:24,150
ni kubwa kuliko
data yako kuweka au kama wewe

363
00:19:24,150 --> 00:19:28,870
wanataka kujaribu na kupunguza chaining
mpaka ni muhimu kabisa.

364
00:19:28,870 --> 00:19:34,050
Hivyo jambo moja ni linear
uchunguzi wazi maana

365
00:19:34,050 --> 00:19:37,290
kwamba hash kazi yako
si kama kabisa muhimu

366
00:19:37,290 --> 00:19:42,200
kwa sababu wewe ni kwenda kuishia kutumia
hash kazi yako, kupata kwa uhakika,

367
00:19:42,200 --> 00:19:46,400
you linear kuchunguza chini
mahali baadhi ya ambayo inapatikana.

368
00:19:46,400 --> 00:19:49,670
Lakini sasa, bila shaka, kitu chochote
kingine kwamba mwisho huko juu,

369
00:19:49,670 --> 00:19:52,050
wewe ni kwenda kuwa na
kutafuta hata zaidi chini.

370
00:19:52,050 --> 00:19:55,650
>> Na kuna mengi zaidi
search gharama kwamba

371
00:19:55,650 --> 00:19:59,820
huenda katika inputting kipengele
katika hash meza yako sasa, haki?

372
00:19:59,820 --> 00:20:05,640
Na sasa wakati wa kwenda na kujaribu na kupata
berry tena, wewe kwenda hash yake,

373
00:20:05,640 --> 00:20:07,742
na ni kwenda kusema,
oh, kuangalia katika ndoo 1,

374
00:20:07,742 --> 00:20:09,700
na si kwenda kuwa na
katika ndoo 1, hivyo wewe ni

375
00:20:09,700 --> 00:20:11,970
kwenda na tindanga
njia ya mapumziko ya haya.

376
00:20:11,970 --> 00:20:17,720
Hivyo ni wakati mwingine muhimu,
lakini katika kesi nyingi,

377
00:20:17,720 --> 00:20:22,660
tunakwenda kusema kwamba
chaining ni nini unataka kufanya.

378
00:20:22,660 --> 00:20:25,520
>> Hivyo sisi aliyesema kuhusu hili mapema.

379
00:20:25,520 --> 00:20:27,812
I got mbele kidogo mwenyewe.

380
00:20:27,812 --> 00:20:33,560
Lakini chaining kimsingi kwamba
kila ndoo katika hash meza yako

381
00:20:33,560 --> 00:20:36,120
ni tu orodha wanaohusishwa.

382
00:20:36,120 --> 00:20:39,660
>> Hivyo njia nyingine, au zaidi ya kiufundi
njia, kufikiria meza hash

383
00:20:39,660 --> 00:20:44,490
ni kwamba ni tu safu
ya orodha wanaohusishwa, ambayo

384
00:20:44,490 --> 00:20:49,330
wakati wewe ni kuandika kamusi yako
na wewe ni kujaribu mzigo,

385
00:20:49,330 --> 00:20:52,070
kufikiri ya kama
safu ya orodha wanaohusishwa

386
00:20:52,070 --> 00:20:54,390
itakuwa kufanya ni rahisi sana
kwa wewe initialize.

387
00:20:54,390 --> 00:20:57,680
>> Watazamaji: Hivyo hash meza
ina ukubwa predetermined,

388
00:20:57,680 --> 00:20:58,980
kama [inaudible] ndoo?

389
00:20:58,980 --> 00:20:59,220
>> SPIKA 1: Haki.

390
00:20:59,220 --> 00:21:01,655
Hivyo ina idadi ya seti ya
ndoo kwamba determine--

391
00:21:01,655 --> 00:21:03,530
ambayo nyie lazima
kujisikia huru kucheza na.

392
00:21:03,530 --> 00:21:05,269
Ni inaweza kuwa pretty baridi
kuona nini kinatokea

393
00:21:05,269 --> 00:21:06,810
kama mabadiliko ya namba yako ya ndoo.

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

395
00:21:09,410 --> 00:21:11,510
Lakini yeah, ina
kuweka idadi ya ndoo.

396
00:21:11,510 --> 00:21:15,360
Nini utapata fit kama
mambo mengi kama unahitaji

397
00:21:15,360 --> 00:21:19,350
ni chaining hii tofauti ambapo wewe
kuwa wanaohusishwa orodha katika kila ndoo.

398
00:21:19,350 --> 00:21:22,850
Hiyo ina maana hash meza yako
itakuwa hasa ukubwa

399
00:21:22,850 --> 00:21:25,440
kwamba unahitaji kuwa, haki?

400
00:21:25,440 --> 00:21:27,358
Hiyo ni hatua nzima ya orodha wanaohusishwa.

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

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

403
00:21:32,480 --> 00:21:38,780
>> Hivyo kila mtu OK huko?

404
00:21:38,780 --> 00:21:39,801
Wote haki.

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

406
00:21:40,300 --> 00:21:41,860
Nini kilichotokea tu?

407
00:21:41,860 --> 00:21:42,960
Kweli sasa.

408
00:21:42,960 --> 00:21:45,250
Nadhani kuna mtu mauaji yangu.

409
00:21:45,250 --> 00:21:52,060
>> OK tunakwenda kwenda katika
inajaribu, ambayo ni mambo kidogo.

410
00:21:52,060 --> 00:21:53,140
Mimi kama meza hash.

411
00:21:53,140 --> 00:21:54,460
Nadhani wao ni kweli baridi.

412
00:21:54,460 --> 00:21:56,710
Inajaribu ni baridi, pia.

413
00:21:56,710 --> 00:21:59,590
>> Hivyo haina mtu yeyote kumbuka kile kujaribu ni?

414
00:21:59,590 --> 00:22:01,740
Unapaswa kuwa wamekwenda juu ya
ni kwa ufupi katika hotuba?

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

416
00:22:04,570 --> 00:22:06,377
Unakumbuka aina ya jinsi kazi?

417
00:22:06,377 --> 00:22:08,460
Watazamaji: Mimi nodding tu
kwamba hatukuwa kwenda juu yake.

418
00:22:08,460 --> 00:22:09,626
SPIKA 1: Hatuna kwenda juu yake.

419
00:22:09,626 --> 00:22:13,100
OK, sisi ni kweli kwenda
juu yake sasa ni nini sisi ni kusema.

420
00:22:13,100 --> 00:22:14,860
>> Watazamaji: Hiyo ni kwa retrieval mti.

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

422
00:22:15,280 --> 00:22:16,196
Ni retrieval mti.

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

424
00:22:16,960 --> 00:22:23,610
Hivyo jambo moja taarifa hapa ni kwamba sisi
ni kuangalia wahusika binafsi

425
00:22:23,610 --> 00:22:24,480
hapa, haki?

426
00:22:24,480 --> 00:22:29,710
>> Hivyo kabla na hash yetu kufanya kazi, sisi
walikuwa kuangalia maneno kwa ujumla,

427
00:22:29,710 --> 00:22:32,270
na sasa sisi ni kuangalia zaidi
katika wahusika, haki?

428
00:22:32,270 --> 00:22:38,380
Hivyo tuna Maxwell juu hapa na Mendel.

429
00:22:38,380 --> 00:22:47,840
Hivyo kimsingi try-- njia ya kufikiri
kuhusu hili ni kwamba kila ngazi hapa

430
00:22:47,840 --> 00:22:49,000
ni safu ya barua.

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

432
00:22:53,310 --> 00:22:55,790
Hivyo hii ni mzizi nodi yako hapa, haki?

433
00:22:55,790 --> 00:23:01,980
Hii ina wahusika wote wa
alfabeti kwa ajili ya kuanza kila neno.

434
00:23:01,980 --> 00:23:06,480
>> Na nini unataka kufanya ni
kusema, OK, tuna baadhi ya neno M.

435
00:23:06,480 --> 00:23:10,590
Sisi ni kwenda kuangalia kwa Maxwell, hivyo
sisi kwenda M. Na M pointi kwa ujumla

436
00:23:10,590 --> 00:23:14,800
mengine safu ambapo kila
neno, kwa muda mrefu kama kuna

437
00:23:14,800 --> 00:23:17,044
ni neno ambayo ina A
kama barua ya pili,

438
00:23:17,044 --> 00:23:19,460
muda mrefu kama kuna neno kwamba
ina B kama barua ya pili,

439
00:23:19,460 --> 00:23:24,630
itakuwa na pointer
kwenda baadhi safu ijayo.

440
00:23:24,630 --> 00:23:29,290
>> Kuna pengine si
neno kwamba mbunge kitu,

441
00:23:29,290 --> 00:23:32,980
hivyo katika P nafasi katika hii
safu, itakuwa tu kuwa null.

442
00:23:32,980 --> 00:23:38,840
Ni kusema, sawa, kuna neno hakuna
kwamba ina M ikifuatiwa na P, sawa?

443
00:23:38,840 --> 00:23:43,100
Hivyo kama sisi kufikiri juu yake, kila
moja ya mambo haya madogo

444
00:23:43,100 --> 00:23:47,990
ni kweli mmoja wa haya
arrays kubwa kutoka A kupitia Z.

445
00:23:47,990 --> 00:23:55,064
Hivyo kile inaweza kuwa moja ya mambo
kwamba ni aina ya drawback ya kujaribu?

446
00:23:55,064 --> 00:23:56,500
>> Watazamaji: mengi ya kumbukumbu.

447
00:23:56,500 --> 00:23:59,940
>> SPIKA 1: Ni tani ya kumbukumbu, haki?

448
00:23:59,940 --> 00:24:08,750
Kila moja ya vitalu haya hapa
inawakilisha nafasi ya 26, 26 kipengele safu.

449
00:24:08,750 --> 00:24:13,680
Hivyo inajaribu kupata incredibly nafasi nzito.

450
00:24:13,680 --> 00:24:17,100
>> Lakini wao ni haraka sana.

451
00:24:17,100 --> 00:24:22,540
Hivyo haraka sana lakini
kweli nafasi ufanisi.

452
00:24:22,540 --> 00:24:24,810
Aina ya kuwa na takwimu
nje ambayo moja unataka.

453
00:24:24,810 --> 00:24:29,470
Hizi ni kweli baridi kwa pset yako,
lakini wao kufanya kuchukua mengi ya kumbukumbu,

454
00:24:29,470 --> 00:24:30,290
hivyo biashara mbali.

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

456
00:24:31,480 --> 00:24:34,300
>> Watazamaji: Je, inawezekana
kuanzisha kujaribu na kisha

457
00:24:34,300 --> 00:24:37,967
mara moja una yote
data katika hilo kuwa wewe need--

458
00:24:37,967 --> 00:24:39,550
Sijui kama kwamba ingekuwa kufanya maana.

459
00:24:39,550 --> 00:24:42,200
Mimi nilikuwa kupata kuondoa wote
Wahusika NULL, lakini basi

460
00:24:42,200 --> 00:24:42,910
ungependa kuwa na uwezo wa ripoti ya them--

461
00:24:42,910 --> 00:24:43,275
>> SPIKA 1: Bado unahitaji yao.

462
00:24:43,275 --> 00:24:44,854
>> Watazamaji: - njia ile ile kila wakati.

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

464
00:24:45,520 --> 00:24:50,460
Unahitaji wahusika NULL basi
unajua kama kuna si neno huko.

465
00:24:50,460 --> 00:24:52,040
Ben hakuwa una kitu unataka?

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

467
00:24:52,540 --> 00:24:54,581
Haki wote, hivyo tunakwenda
kwenda kidogo zaidi

468
00:24:54,581 --> 00:24:58,920
undani wa kiufundi nyuma
a kujaribu na kazi kwa njia ya mfano.

469
00:24:58,920 --> 00:25:01,490
>> OK, hivyo hii ni kitu kimoja.

470
00:25:01,490 --> 00:25:06,290
Ambapo katika orodha wanaohusishwa, kuu yetu
aina of-- nini neno nataka? -

471
00:25:06,290 --> 00:25:08,350
kama kujenga block ilikuwa nodi.

472
00:25:08,350 --> 00:25:12,280
Katika kujaribu, sisi pia kuwa nodi,
lakini ni defined tofauti.

473
00:25:12,280 --> 00:25:17,000
>> Hivyo tuna baadhi bool kwamba
inawakilisha kama neno kweli

474
00:25:17,000 --> 00:25:23,530
lipo katika eneo hili, na kisha
tuna baadhi ya safu here-- au tuseme,

475
00:25:23,530 --> 00:25:27,840
hii ni pointer
safu ya wahusika 27.

476
00:25:27,840 --> 00:25:33,339
Na hii ni kwa ajili ya, katika kesi hii, hii
27-- mimi nina uhakika wote wa wewe ni kama, kusubiri,

477
00:25:33,339 --> 00:25:34,880
kuna barua 26 katika alfabeti.

478
00:25:34,880 --> 00:25:36,010
Kwa nini tuna 27?

479
00:25:36,010 --> 00:25:37,870
>> Hivyo kutegemea
njia wewe kutekeleza huu,

480
00:25:37,870 --> 00:25:43,240
hii ni kutoka pset kwamba
kuruhusiwa kwa apostrophes.

481
00:25:43,240 --> 00:25:46,010
Hivyo kwamba ni kwa nini moja ya ziada.

482
00:25:46,010 --> 00:25:50,500
Utasikia pia kuwa katika baadhi ya
kesi null Terminator

483
00:25:50,500 --> 00:25:53,230
ni pamoja kama moja ya
wahusika kwamba ni kuruhusiwa kuwa,

484
00:25:53,230 --> 00:25:56,120
na kwamba ni jinsi wao kuangalia
kuona kama ni mwisho wa neno.

485
00:25:56,120 --> 00:26:01,340
Kama wewe ni nia, angalia
Video Kevin juu study.cs50,

486
00:26:01,340 --> 00:26:04,790
vile vile Wikipedia ina
baadhi rasilimali nzuri huko.

487
00:26:04,790 --> 00:26:09,000
>> Lakini sisi ni kwenda kupitia tu aina
jinsi unavyoweza kazi kwa njia ya kujaribu

488
00:26:09,000 --> 00:26:11,010
kama wewe ni kupewa moja.

489
00:26:11,010 --> 00:26:16,230
Hivyo tuna moja super rahisi hapa kwamba
ina maneno "popo" na "zoom" katika wao.

490
00:26:16,230 --> 00:26:18,920
Na kama sisi kuona hapa,
hii nafasi kidogo hapa

491
00:26:18,920 --> 00:26:22,560
inawakilisha bool yetu kwamba
anasema, ndiyo, hii ni neno.

492
00:26:22,560 --> 00:26:27,060
Na kisha hii ina zetu
arrays ya wahusika, haki?

493
00:26:27,060 --> 00:26:33,480
>> Hivyo sisi ni kwenda kupitia
kutafuta "popo" katika kujaribu hili.

494
00:26:33,480 --> 00:26:38,340
Hivyo kuanza saa ya juu, haki?

495
00:26:38,340 --> 00:26:46,290
Na tunajua kwamba b sambamba na
ripoti ya pili, kipengele cha pili

496
00:26:46,290 --> 00:26:47,840
katika safu hii, kwa sababu na b.

497
00:26:47,840 --> 00:26:51,340
Hivyo takriban moja ya pili.

498
00:26:51,340 --> 00:26:58,820
>> Na inasema, OK, baridi, kufuata kwamba katika
safu ya pili, kwa sababu kama sisi kukumbuka,

499
00:26:58,820 --> 00:27:02,160
si kwamba kila moja ya haya
kweli ina kipengele.

500
00:27:02,160 --> 00:27:07,110
Kila moja ya arrays haya
ina pointer, haki?

501
00:27:07,110 --> 00:27:10,030
Ni tofauti muhimu kufanya.

502
00:27:10,030 --> 00:27:13,450
>> Najua hii ni kwenda be-- inajaribu ni
kweli ni vigumu kupata mara ya kwanza,

503
00:27:13,450 --> 00:27:15,241
hivyo hata kama hii ni
mara ya pili au ya tatu

504
00:27:15,241 --> 00:27:18,370
na ni bado aina
ya Wanajidai vigumu,

505
00:27:18,370 --> 00:27:21,199
Mimi ahadi kama wewe kwenda kuangalia
short tena kesho,

506
00:27:21,199 --> 00:27:22,740
utakuwa pengine mantiki mengi zaidi.

507
00:27:22,740 --> 00:27:23,890
Inachukua mengi Digest.

508
00:27:23,890 --> 00:27:27,800
Mimi bado wakati mwingine ni
kama, kusubiri, ni nini kujaribu?

509
00:27:27,800 --> 00:27:29,080
Je, mimi kutumia hili?

510
00:27:29,080 --> 00:27:33,880
>> Hivyo tuna b katika kesi hii,
ambayo ni ya pili ripoti yetu.

511
00:27:33,880 --> 00:27:40,240
Kama tungekuwa na, kusema, c au
d au barua nyingine yoyote,

512
00:27:40,240 --> 00:27:45,810
tunahitaji ramani kwamba nyuma ya ripoti ya
safu yetu kwamba kwamba sambamba na.

513
00:27:45,810 --> 00:27:56,930
Hivyo tunataka kuchukua kama rchar na sisi tu
Ondoa mbali ramani ndani 0-25.

514
00:27:56,930 --> 00:27:58,728
Kila mtu mwema jinsi sisi
ramani wahusika zetu?

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

516
00:28:00,440 --> 00:28:05,980
>> Hivyo sisi kwenda moja ya pili na sisi
kuona kwamba, ndiyo, ni si null.

517
00:28:05,980 --> 00:28:07,780
Tunaweza kuendelea na safu hii ijayo.

518
00:28:07,780 --> 00:28:12,300
Hivyo sisi kwenda kwenye safu hii ya pili hapa.

519
00:28:12,300 --> 00:28:15,500
>> Na sisi kusema, sawa, sasa sisi
haja ya kuona kama ni hapa.

520
00:28:15,500 --> 00:28:18,590
Ni null au gani
kweli kusonga mbele?

521
00:28:18,590 --> 00:28:21,880
Hivyo kweli hatua
mbele katika safu hii.

522
00:28:21,880 --> 00:28:24,570
Na sisi kusema, sawa, t ni barua yetu ya mwisho.

523
00:28:24,570 --> 00:28:27,580
Hivyo sisi kwenda t katika ripoti.

524
00:28:27,580 --> 00:28:30,120
Na kisha sisi kusonga mbele
kwa sababu kuna mtu mwingine.

525
00:28:30,120 --> 00:28:38,340
Na hii moja anasema kimsingi kwamba, ndiyo,
inasema kwamba kuna neno here--

526
00:28:38,340 --> 00:28:41,750
kwamba kama wewe kufuata hii
njia, wewe wamewasili

527
00:28:41,750 --> 00:28:43,210
katika neno, ambayo sisi kujua ni "popo."

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

529
00:28:43,800 --> 00:28:46,770
>> Watazamaji: Je, ni kiwango kuwa na kwamba
kama index 0 na kisha kuwa na aina katika 1

530
00:28:46,770 --> 00:28:47,660
au kuwa na mwishoni?

531
00:28:47,660 --> 00:28:48,243
>> SPIKA 1: Hapana

532
00:28:48,243 --> 00:28:55,360
Hivyo kama sisi kuangalia nyuma katika yetu
tamko hapa, ni bool,

533
00:28:55,360 --> 00:28:59,490
hivyo ni kipengele yake mwenyewe katika nodi yako.

534
00:28:59,490 --> 00:29:03,331
Hivyo si sehemu ya safu.

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

536
00:29:03,830 --> 00:29:08,370
Hivyo wakati sisi kumaliza neno yetu na tuko
katika safu hii, nini tunataka kufanya

537
00:29:08,370 --> 00:29:12,807
ni kufanya kuangalia kwa hii neno.

538
00:29:12,807 --> 00:29:14,390
Na katika kesi hii, itakuwa kurudi ndiyo.

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

540
00:29:17,220 --> 00:29:24,090
>> Kadhalika kwamba kumbuka, tunajua kwamba "zoo" -
sisi kujua kama binadamu kwamba "zoo" ni neno,

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

542
00:29:24,820 --> 00:29:28,990
Lakini ni kujaribu hapa ingekuwa
kusema, hakuna, siyo.

543
00:29:28,990 --> 00:29:33,980
Na kusema kwamba kwa sababu sisi
si mteule kama neno hapa.

544
00:29:33,980 --> 00:29:40,440
Ingawa tunaweza traverse
kupitia kwa safu hii,

545
00:29:40,440 --> 00:29:43,890
kujaribu hii kusema kwamba, hakuna,
zoo si katika kamusi yako

546
00:29:43,890 --> 00:29:47,070
kwa sababu tuna si
mteule kama vile.

547
00:29:47,070 --> 00:29:52,870
>> Hivyo njia moja ya kufanya that--
oh, sorry, hii moja.

548
00:29:52,870 --> 00:29:59,450
Hivyo katika kesi hii, "zoo" si
neno, lakini ni katika kujaribu yetu.

549
00:29:59,450 --> 00:30:05,690
Lakini katika hii moja, wanasema tunataka
kuanzisha neno "kuoga," nini kinatokea

550
00:30:05,690 --> 00:30:08,260
ni sisi kufuata through-- b,, t.

551
00:30:08,260 --> 00:30:11,820
Tuko katika safu hii, na
sisi kwenda kutafuta h.

552
00:30:11,820 --> 00:30:15,220
>> Katika kesi hiyo, wakati sisi
kuangalia pointer katika h,

553
00:30:15,220 --> 00:30:17,890
ni akizungumzia null, sawa?

554
00:30:17,890 --> 00:30:20,780
Hivyo isipokuwa ni wazi
akizungumzia safu mwingine,

555
00:30:20,780 --> 00:30:25,000
kudhani kwamba kuyatumia yote
katika safu hii ni akizungumzia null.

556
00:30:25,000 --> 00:30:28,270
Hivyo katika kesi hii, h ni akizungumzia
kwa null hivyo hatuwezi kufanya kitu chochote,

557
00:30:28,270 --> 00:30:31,540
hivyo itakuwa pia kurudi
uongo, "bath" si katika hapa.

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

559
00:30:34,102 --> 00:30:35,810
Hivyo sasa sisi ni kweli
kwenda kupitia

560
00:30:35,810 --> 00:30:39,790
jinsi gani sisi kweli kusema
kwamba "zoo" ni katika kujaribu yetu.

561
00:30:39,790 --> 00:30:42,920
Jinsi gani sisi kuingiza "zoo" katika kujaribu yetu?

562
00:30:42,920 --> 00:30:47,810
Hivyo katika njia sawa kwamba sisi ilianza na
orodha yetu wanaohusishwa, sisi kuanza saa mizizi.

563
00:30:47,810 --> 00:30:50,600
Wakati katika shaka, kuanza saa
mizizi ya mambo haya.

564
00:30:50,600 --> 00:30:53,330
>> Na tutaweza kusema, sawa, z.

565
00:30:53,330 --> 00:30:55,650
z ipo katika hili, na ni gani.

566
00:30:55,650 --> 00:30:58,370
Hivyo wewe ni kuhamia kwenye
safu yako ijayo, sawa?

567
00:30:58,370 --> 00:31:01,482
Na kisha kwenye moja ya pili,
sisi kusema, sawa, haina o zipo?

568
00:31:01,482 --> 00:31:03,000
Ni gani.

569
00:31:03,000 --> 00:31:04,330
Hii tena.

570
00:31:04,330 --> 00:31:08,670
>> Na kadhalika moja yetu ijayo, tumekuwa alisema,
OK, "zoo" tayari lipo hapa.

571
00:31:08,670 --> 00:31:12,440
Wote tunahitaji kufanya ni kuweka hii sawa
kwa kweli, kwamba kuna neno pale.

572
00:31:12,440 --> 00:31:15,260
Kama alikuwa na kufuatiwa kila kitu
hadi kabla ya hatua hiyo,

573
00:31:15,260 --> 00:31:17,030
ni neno, hivyo tu
kuweka sawa na hayo.

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

575
00:31:17,530 --> 00:31:22,550
>> Watazamaji: Hivyo basi gani kwamba
maana kwamba "ba" ni neno pia?

576
00:31:22,550 --> 00:31:24,120
>> SPIKA 1: Hapana

577
00:31:24,120 --> 00:31:28,870
Hivyo katika kesi hii, "ba" tunataka kupata
hapa, tunataka kusema ni neno,

578
00:31:28,870 --> 00:31:31,590
na bado ingekuwa hakuna.

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
>> Watazamaji: Hivyo mara moja wewe ni
neno na kusema ndiyo, basi ni

582
00:31:36,360 --> 00:31:38,380
vyenye kwenda m?

583
00:31:38,380 --> 00:31:42,260
>> SPIKA 1: Hivyo hii ina kufanya
with-- wewe ni upakiaji huu katika.

584
00:31:42,260 --> 00:31:43,640
Wewe kusema "zoo" ni neno.

585
00:31:43,640 --> 00:31:47,020
Baada ya kwenda kwa check--
kama, kusema unataka kusema,

586
00:31:47,020 --> 00:31:49,400
haina "zoo" zipo katika kamusi hii?

587
00:31:49,400 --> 00:31:54,200
Wewe ni kwenda tu kutafuta "zoo"
na kisha kuangalia kuona kama ni neno.

588
00:31:54,200 --> 00:31:57,291
Wewe kamwe kwenda kwa hoja
kupitia kwa m sababu si kwamba

589
00:31:57,291 --> 00:31:58,290
nini wewe kutafuta.

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

591
00:32:02,690 --> 00:32:08,070
>> Hivyo kama sisi kweli alitaka
kuongeza "bath" katika kujaribu hii,

592
00:32:08,070 --> 00:32:11,390
tunataka kufanya kitu kimoja
kama tulivyofanya na "zoo"

593
00:32:11,390 --> 00:32:15,380
ila tunataka kuona kwamba wakati sisi
kujaribu na kupata h, haipo.

594
00:32:15,380 --> 00:32:20,090
Hivyo unaweza kufikiria hili kama kujaribu
kuongeza nodi mpya katika orodha wanaohusishwa,

595
00:32:20,090 --> 00:32:27,210
hivyo tunataka haja ya kuongeza mwingine
moja ya arrays haya, kama hivyo.

596
00:32:27,210 --> 00:32:35,670
Na kisha nini sisi ni sisi tu ya kuweka h
kipengele cha safu hii akizungumzia hii.

597
00:32:35,670 --> 00:32:39,430
>> Na kisha gani tunataka kufanya hapa?

598
00:32:39,430 --> 00:32:43,110
Kuongeza sawa na kweli
sababu ni neno.

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

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

601
00:32:48,150 --> 00:32:48,700
Mimi najua.

602
00:32:48,700 --> 00:32:51,170
Inajaribu si kusisimua zaidi.

603
00:32:51,170 --> 00:32:54,250
Matumaini yangu, najua.

604
00:32:54,250 --> 00:32:58,040
>> Hivyo jambo moja kwa kutambua na inajaribu,
Mimi alisema, wao ni ufanisi sana.

605
00:32:58,040 --> 00:33:00,080
Hivyo tumeona wao
kuchukua tani ya nafasi.

606
00:33:00,080 --> 00:33:01,370
Wao ni aina ya utata.

607
00:33:01,370 --> 00:33:03,367
Hivyo ni kwa nini sisi milele kutumia haya?

608
00:33:03,367 --> 00:33:05,450
Sisi kutumia haya kwa sababu wao ni
incredibly ufanisi.

609
00:33:05,450 --> 00:33:08,130
>> Hivyo kama wewe ni milele kuangalia
neno, wewe ni tu

610
00:33:08,130 --> 00:33:10,450
imepakana na urefu wa neno.

611
00:33:10,450 --> 00:33:15,210
Hivyo kama wewe ni kuangalia kwa
neno kwamba ni ya urefu tano,

612
00:33:15,210 --> 00:33:20,940
wewe ni milele tu kwenda na
kufanya saa zaidi kulinganisha tano, sawa?

613
00:33:20,940 --> 00:33:25,780
Hivyo inafanya kimsingi mara kwa mara.

614
00:33:25,780 --> 00:33:29,150
Kama insertion na Luke
ni wakati wa mara kwa mara kimsingi.

615
00:33:29,150 --> 00:33:33,750
>> Hivyo kama unaweza milele kupata
kitu katika muda wa mara kwa mara,

616
00:33:33,750 --> 00:33:35,150
hiyo ni kama nzuri kama anapata.

617
00:33:35,150 --> 00:33:37,990
Huwezi kupata bora kuliko
wakati mara kwa mara kwa ajili ya mambo haya.

618
00:33:37,990 --> 00:33:43,150
Hivyo kwamba ni moja ya
pluses mkubwa ya anajaribu.

619
00:33:43,150 --> 00:33:46,780
>> Lakini ni nafasi kubwa mno.

620
00:33:46,780 --> 00:33:50,380
Hivyo aina ya kuwa na kuamua
nini muhimu zaidi na wewe.

621
00:33:50,380 --> 00:33:54,700
Na juu ya kompyuta ya leo,
nafasi hiyo kujaribu inaweza kuchukua hadi

622
00:33:54,700 --> 00:33:57,740
labda haina kuathiri
kwamba mengi, lakini labda

623
00:33:57,740 --> 00:34:01,350
wewe ni kushughulika na kitu
ambayo ina mambo mbali, mbali zaidi,

624
00:34:01,350 --> 00:34:02,810
na kujaribu si tu nafuu.

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

626
00:34:03,000 --> 00:34:05,610
>> Watazamaji: Ngoja, hivyo una 26
barua katika kila moja?

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

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

629
00:34:08,570 --> 00:34:16,984
Una baadhi ni alama neno na kisha
una 26 kuyatumia katika kila moja.

630
00:34:16,984 --> 00:34:17,775
Na wao ni point--

631
00:34:17,775 --> 00:34:20,280
>> Watazamaji: Na kila 26,
gani wao kila mmoja kuwa 26?

632
00:34:20,280 --> 00:34:21,500
>> SPIKA 1: Ndiyo.

633
00:34:21,500 --> 00:34:27,460
Na kwamba ni kwa nini, kama unaweza
kuona, expands haraka kabisa.

634
00:34:27,460 --> 00:34:28,130
Wote haki.

635
00:34:28,130 --> 00:34:32,524
Hivyo sisi ni kwenda kupata katika miti, ambayo
Najisikia kama ni rahisi na pengine

636
00:34:32,524 --> 00:34:36,150
kuwa nzuri ahueni kidogo
kutoka inajaribu huko.

637
00:34:36,150 --> 00:34:39,620
Hivyo hopefully zaidi ya wewe
tumeona mti kabla.

638
00:34:39,620 --> 00:34:41,820
Si kama pretty
ndio nje, ambayo mimi

639
00:34:41,820 --> 00:34:44,340
sijui kama mtu yeyote
akaenda nje hivi karibuni.

640
00:34:44,340 --> 00:34:49,230
Nilikwenda apple kuokota mwishoni mwa wiki hii,
na oh gosh yangu, ilikuwa nzuri.

641
00:34:49,230 --> 00:34:52,250
Sikujua majani
inaweza kuangalia kwamba pretty.

642
00:34:52,250 --> 00:34:53,610
>> Hivyo hii ni tu mti, haki?

643
00:34:53,610 --> 00:34:56,790
Ni baadhi tu ya nodi, na
anazungumzia rundo la nodes nyingine.

644
00:34:56,790 --> 00:34:59,570
Kama unaweza kuona hapa, hii ni
aina ya mandhari ya mara kwa mara.

645
00:34:59,570 --> 00:35:03,720
Vituo akizungumzia nodes ni aina ya
kiini cha miundo wengi data.

646
00:35:03,720 --> 00:35:06,670
Ni tu inategemea jinsi sisi
kuwa nao uhakika na kila mmoja

647
00:35:06,670 --> 00:35:08,600
na jinsi sisi traverse
njia yao na jinsi sisi

648
00:35:08,600 --> 00:35:14,500
kuingiza mambo ambayo huamua
sifa zao tofauti.

649
00:35:14,500 --> 00:35:17,600
>> Hivyo baadhi tu istilahi,
ambayo nimekuwa kutumika kabla.

650
00:35:17,600 --> 00:35:20,010
Hivyo mzizi ni chochote ni saa ya juu sana.

651
00:35:20,010 --> 00:35:21,200
ni mahali ambapo sisi daima kuanza.

652
00:35:21,200 --> 00:35:23,610
Unaweza kufikiria kama kichwa pia.

653
00:35:23,610 --> 00:35:28,750
Lakini kwa ajili ya miti, sisi huwa na
rejea ni kama mizizi.

654
00:35:28,750 --> 00:35:32,820
>> Chochote wakati here-- chini
katika sana, bottom-- sana

655
00:35:32,820 --> 00:35:34,500
ni kuchukuliwa majani.

656
00:35:34,500 --> 00:35:37,210
Hivyo huenda pamoja na
mti mzima jambo, haki?

657
00:35:37,210 --> 00:35:39,860
Majani ni pembezoni ya mti yako.

658
00:35:39,860 --> 00:35:45,820
>> Na kisha sisi pia kuwa wanandoa wa
suala kwa majadiliano juu ya nodes katika uhusiano

659
00:35:45,820 --> 00:35:46,680
kwa kila mmoja.

660
00:35:46,680 --> 00:35:49,700
Hivyo tuna mzazi,
watoto, na ndugu zake.

661
00:35:49,700 --> 00:35:56,260
Hivyo katika kesi hii, 3 ni
mzazi wa 5, 6 na 7.

662
00:35:56,260 --> 00:36:00,370
Hivyo mzazi ni chochote ni
hatua moja juu ya chochote ni

663
00:36:00,370 --> 00:36:02,940
akimaanisha, hivyo tu
kama mti familia.

664
00:36:02,940 --> 00:36:07,090
Hopefully, hii ni kidogo wote
kidogo zaidi Intuitive kuliko anajaribu.

665
00:36:07,090 --> 00:36:10,970
>> Ndugu ni yoyote kwamba kuwa
mzazi sawa, haki?

666
00:36:10,970 --> 00:36:13,470
Wao uko juu ya kiwango sawa hapa.

667
00:36:13,470 --> 00:36:16,960
Na kisha, kama mimi nilikuwa
akisema, watoto ni tu

668
00:36:16,960 --> 00:36:22,630
chochote ni hatua moja chini
nodi katika swali, sawa?

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

670
00:36:23,470 --> 00:36:25,610
Hivyo mti binary.

671
00:36:25,610 --> 00:36:31,450
Je, mtu yeyote athari ya nadhani kwenye moja ya
sifa za mti binary?

672
00:36:31,450 --> 00:36:32,770
>> Watazamaji: Max majani mawili.

673
00:36:32,770 --> 00:36:33,478
>> SPIKA 1: Haki.

674
00:36:33,478 --> 00:36:34,640
Hivyo max ya majani mawili.

675
00:36:34,640 --> 00:36:39,730
Hivyo katika hii moja kabla, tulikuwa hii moja
kwamba alikuwa tatu, lakini katika mti binary,

676
00:36:39,730 --> 00:36:45,000
una max ya mbili
watoto kwa kila mzazi, haki?

677
00:36:45,000 --> 00:36:46,970
Kuna mwingine
kuvutia tabia.

678
00:36:46,970 --> 00:36:51,550
Je, mtu yeyote kujua kwamba?

679
00:36:51,550 --> 00:36:52,620
Binary mti.

680
00:36:52,620 --> 00:37:00,350
>> Hivyo mti binary itakuwa na kila kitu
juu ya the-- moja hii si sorted--

681
00:37:00,350 --> 00:37:05,320
lakini katika yamepangwa binary mti,
kila kitu juu ya haki

682
00:37:05,320 --> 00:37:08,530
ni mkubwa kuliko mzazi,
na kila kitu juu ya kushoto

683
00:37:08,530 --> 00:37:10,035
ni chini ya mzazi.

684
00:37:10,035 --> 00:37:15,690
Na kwamba imekuwa Jaribio
swali kabla, hivyo vizuri kujua.

685
00:37:15,690 --> 00:37:19,500
Hivyo njia sisi kufafanua hii,
tena, tuna nodi nyingine.

686
00:37:19,500 --> 00:37:21,880
Hii inaonekana ni sawa na nini?

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

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

689
00:37:28,836 --> 00:37:29,320
>> Watazamaji: Wanaohusishwa orodha

690
00:37:29,320 --> 00:37:31,100
>> SPIKA 1: maradufu orodha wanaohusishwa, haki?

691
00:37:31,100 --> 00:37:33,690
Hivyo kama sisi kuchukua nafasi ya hii
na uliopita na wa pili,

692
00:37:33,690 --> 00:37:35,670
hii itakuwa orodha doubly wanaohusishwa.

693
00:37:35,670 --> 00:37:40,125
Lakini katika kesi hii, sisi kweli
kuwa kushoto na kulia na hiyo ni yake.

694
00:37:40,125 --> 00:37:41,500
Vinginevyo, ni sawa.

695
00:37:41,500 --> 00:37:43,374
Bado tuna kipengele
wewe ni kuangalia kwa,

696
00:37:43,374 --> 00:37:45,988
na wewe tu kuyatumia mbili
kwenda chochote ijayo.

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

698
00:37:49,210 --> 00:37:51,870
Yeah, hivyo binary tafuta mti.

699
00:37:51,870 --> 00:37:57,665
Kama sisi taarifa, kila kitu juu ya
haki hapa ni than-- zaidi

700
00:37:57,665 --> 00:37:59,850
au kila kitu mara moja
na haki hapa

701
00:37:59,850 --> 00:38:02,840
ni mkubwa kuliko, kila kitu
hapa ni chini ya.

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

703
00:38:06,980 --> 00:38:14,000
>> Hivyo kama sisi walikuwa na kutafuta njia ya, ni
inapaswa kuangalia karibu sana na binary tafuta

704
00:38:14,000 --> 00:38:14,910
hapa, haki?

705
00:38:14,910 --> 00:38:17,640
Isipokuwa badala ya kuangalia
katika nusu safu,

706
00:38:17,640 --> 00:38:21,720
sisi ni kuangalia tu katika aidha kushoto
upande au upande wa kulia wa mti.

707
00:38:21,720 --> 00:38:24,850
Hivyo anapata kidogo rahisi, nadhani.

708
00:38:24,850 --> 00:38:29,300
>> Hivyo kama mizizi yako ni null,
wazi ni tu ya uongo.

709
00:38:29,300 --> 00:38:33,470
Na kama ni huko, ni wazi ni kweli.

710
00:38:33,470 --> 00:38:35,320
Kama ni chini ya, sisi kutafuta kushoto.

711
00:38:35,320 --> 00:38:37,070
Kama ni kubwa kuliko,
sisi kutafuta haki.

712
00:38:37,070 --> 00:38:39,890
Ni hasa kama search binary,
tu muundo tofauti data

713
00:38:39,890 --> 00:38:40,600
kwamba sisi ni kutumia.

714
00:38:40,600 --> 00:38:42,790
Badala ya safu,
ni tu mti binary.

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

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

717
00:38:48,090 --> 00:38:51,550
Na pia, inaonekana kama sisi
anaweza kuwa kidogo ya muda.

718
00:38:51,550 --> 00:38:54,460
Kama sisi kufanya, mimi nina furaha na kwenda
juu ya yoyote ya hii tena.

719
00:38:54,460 --> 00:38:56,856
OK, hivyo mwingi.

720
00:38:56,856 --> 00:39:02,695
Je, mtu yeyote kumbuka kile stacks--
sifa yoyote ya stack?

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

722
00:39:05,550 --> 00:39:10,400
>> OK, hivyo wengi wetu, nadhani,
kula katika dining halls--

723
00:39:10,400 --> 00:39:13,100
kama vile sisi inaweza si kama.

724
00:39:13,100 --> 00:39:16,900
Lakini ni wazi, unaweza kufikiria stack
literally tu kama stack ya trays

725
00:39:16,900 --> 00:39:18,460
au stack ya mambo.

726
00:39:18,460 --> 00:39:21,820
Na nini muhimu
kutambua ni kwamba ni

727
00:39:21,820 --> 00:39:26,850
something-- tabia
kwamba sisi kuiita by-- ni LIFO.

728
00:39:26,850 --> 00:39:28,450
Je, mtu yeyote kujua nini kwamba anasimama kwa ajili ya?

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

730
00:39:29,070 --> 00:39:30,650
>> Watazamaji: Mwisho, kwanza nje.

731
00:39:30,650 --> 00:39:32,250
>> SPIKA 1: Haki, mwisho katika, kwanza nje.

732
00:39:32,250 --> 00:39:36,585
Hivyo kama sisi kujua, kama sisi ni stacking vitu
up, jambo rahisi kunyakua off--

733
00:39:36,585 --> 00:39:39,570
na labda jambo pekee tunaweza kunyakua
mbali kama stack yetu ni enough-- kubwa

734
00:39:39,570 --> 00:39:40,850
ni kipengele kwamba juu.

735
00:39:40,850 --> 00:39:43,460
Hivyo chochote ilikuwa kuweka kwenye
last-- kama tunaona hapa,

736
00:39:43,460 --> 00:39:46,370
chochote alikuwa kusukuma
juu zaidi recently-- ni

737
00:39:46,370 --> 00:39:51,160
itakuwa ya kwanza
Jambo kwamba sisi pop mbali, sawa?

738
00:39:51,160 --> 00:39:56,324
>> Hivyo nini sisi hapa ni
mwingine typedef struct.

739
00:39:56,324 --> 00:39:58,740
Hii ni kweli tu kama
ajali shaka katika muundo data,

740
00:39:58,740 --> 00:40:01,650
hivyo kuna mengi kutupwa katika wewe guys.

741
00:40:01,650 --> 00:40:02,540
Mimi najua.

742
00:40:02,540 --> 00:40:04,970
Hivyo bado struct nyingine.

743
00:40:04,970 --> 00:40:06,740
Yay kwa miundo.

744
00:40:06,740 --> 00:40:16,660
>> Na katika kesi hii, ni baadhi pointer
safu ambayo ina baadhi ya uwezo.

745
00:40:16,660 --> 00:40:20,830
Hivyo hii inawakilisha stack yetu
hapa, kama safu yetu halisi

746
00:40:20,830 --> 00:40:22,520
hiyo ni kufanya mambo yetu.

747
00:40:22,520 --> 00:40:24,850
Na kisha hapa tuna baadhi ya kawaida.

748
00:40:24,850 --> 00:40:31,170
>> Na kawaida, unataka kuweka
wimbo wa jinsi kubwa stack yako ni

749
00:40:31,170 --> 00:40:36,180
kwa sababu kile ni kwenda kuruhusu
wewe kufanya ni kama unajua ukubwa,

750
00:40:36,180 --> 00:40:39,170
utapata kusema,
OK, mimi katika uwezo?

751
00:40:39,170 --> 00:40:40,570
Naweza kuongeza chochote zaidi?

752
00:40:40,570 --> 00:40:44,650
Na pia atakwambia
ambapo juu ya stack yako

753
00:40:44,650 --> 00:40:48,180
ni hivyo unajua nini
unaweza kweli kuchukua mbali.

754
00:40:48,180 --> 00:40:51,760
Na kwamba kweli kwenda
kuwa zaidi kidogo ya wazi hapa.

755
00:40:51,760 --> 00:40:57,350
>> Hivyo kwa kushinikiza, jambo moja, kama wewe
walikuwa milele kutekeleza kushinikiza,

756
00:40:57,350 --> 00:41:01,330
kama mimi alikuwa akisema tu, yako
stack ina ukubwa mdogo, haki?

757
00:41:01,330 --> 00:41:03,990
Safu yetu alikuwa na baadhi ya uwezo.

758
00:41:03,990 --> 00:41:04,910
Ni safu.

759
00:41:04,910 --> 00:41:08,930
Ni fasta ukubwa, hivyo tunahitaji
kuhakikisha kwamba sisi siyo kuweka zaidi

760
00:41:08,930 --> 00:41:11,950
katika safu yetu kuliko sisi
kweli kuwa nafasi kwa.

761
00:41:11,950 --> 00:41:16,900
>> Hivyo wakati wewe ni kujenga kushinikiza
kazi, jambo la kwanza kufanya ni kusema, sawa,

762
00:41:16,900 --> 00:41:18,570
kufanya mimi kuwa na nafasi katika stack yangu?

763
00:41:18,570 --> 00:41:23,330
Kwa sababu kama mimi si, pole,
Siwezi kuhifadhi kipengele yako.

764
00:41:23,330 --> 00:41:28,980
Kama mimi kufanya, basi unataka kuhifadhi
ni juu ya stack, haki?

765
00:41:28,980 --> 00:41:31,325
>> Na hii ni kwa nini tuna
kuweka wimbo wa kawaida yetu.

766
00:41:31,325 --> 00:41:35,290
Kama hatuwezi kuweka wimbo wa kawaida yetu,
hatujui ambapo kuweka.

767
00:41:35,290 --> 00:41:39,035
Hatujui mambo ngapi
ni katika safu yetu tayari.

768
00:41:39,035 --> 00:41:41,410
Kama ni wazi kuna njia
kwamba labda unaweza kufanya hivyo.

769
00:41:41,410 --> 00:41:44,610
Unaweza initialize kila kitu kwa null
na kisha kuangalia kwa ajili ya karibuni NULL,

770
00:41:44,610 --> 00:41:47,950
lakini jambo rahisi tu
kusema, sawa, kuweka wimbo wa kawaida.

771
00:41:47,950 --> 00:41:51,840
Kama Mimi najua kuwa mambo manne
katika safu yangu, hivyo jambo la pili

772
00:41:51,840 --> 00:41:55,930
kwamba sisi kuweka juu, sisi ni
kwenda kuhifadhi katika ripoti 4.

773
00:41:55,930 --> 00:42:00,940
Na kisha, bila shaka, hii ina maana kwamba
umefanya mafanikio kusukuma kitu

774
00:42:00,940 --> 00:42:03,320
kwenye stack yako,
wanataka kuongeza ukubwa

775
00:42:03,320 --> 00:42:08,880
ili kujua ambapo wewe ni hivyo
kwamba unaweza kushinikiza mambo zaidi juu ya.

776
00:42:08,880 --> 00:42:12,730
>> Hivyo kama sisi ni kujaribu pop
kitu mbali ya stack,

777
00:42:12,730 --> 00:42:16,072
nini inaweza kuwa jambo la kwanza
kwamba tunataka kuangalia kwa?

778
00:42:16,072 --> 00:42:18,030
Wewe ni kujaribu kuchukua
kitu mbali ya stack yako.

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

780
00:42:21,710 --> 00:42:24,781
Je, una hakika kuna
kitu katika stack yako?

781
00:42:24,781 --> 00:42:25,280
Hakuna

782
00:42:25,280 --> 00:42:26,894
Hivyo nini kinaweza tunataka kuangalia?

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

784
00:42:27,810 --> 00:42:29,880
SPIKA 1: Angalia kwa kawaida?

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

786
00:42:31,840 --> 00:42:38,520
Hivyo tunataka kuangalia kuona kama
ukubwa yetu ni kubwa kuliko 0, sawa?

787
00:42:38,520 --> 00:42:44,970
Na kama ni, basi tunataka kupunguza
kawaida yetu na 0 na kurudi kwamba.

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

789
00:42:45,840 --> 00:42:49,950
>> Katika moja ya kwanza tulikuwa
kusukuma, sisi kusukuma yake

790
00:42:49,950 --> 00:42:52,460
kwenye ukubwa na kisha updated kawaida.

791
00:42:52,460 --> 00:42:57,850
Katika kesi hii, sisi ni decrementing ukubwa
na kisha kuchukua ni mbali, kukwanyua ni

792
00:42:57,850 --> 00:42:58,952
kutoka safu yetu.

793
00:42:58,952 --> 00:42:59,826
Kwa nini huenda sisi kufanya hivyo?

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

795
00:43:04,800 --> 00:43:11,811
Hivyo kama nina jambo moja juu ya stack yangu,
nini itakuwa kawaida yangu katika hatua hiyo?

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

797
00:43:13,140 --> 00:43:15,180
>> Na ambapo ni kipengele 1 kuhifadhiwa?

798
00:43:15,180 --> 00:43:17,621
Nini ripoti?

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

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

801
00:43:19,060 --> 00:43:22,800
Hivyo katika kesi hii, sisi
daima haja ya kufanya sure--

802
00:43:22,800 --> 00:43:27,630
badala ya kurudi
ukubwa minus 1, kwa sababu sisi

803
00:43:27,630 --> 00:43:31,730
kujua kwamba kipengele yetu ni
kwenda kuhifadhiwa katika 1 chini

804
00:43:31,730 --> 00:43:34,705
chochote kawaida yetu ni, hii
tu inachukua huduma hiyo.

805
00:43:34,705 --> 00:43:36,080
Ni njia kidogo zaidi ya kifahari.

806
00:43:36,080 --> 00:43:41,220
Na sisi tu ya mapunguzo wetu
ukubwa na kisha kurudi kawaida.

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

808
00:43:42,330 --> 00:43:45,300
>> Watazamaji: Mimi nadhani tu kwa ujumla,
kwa nini muundo huu data

809
00:43:45,300 --> 00:43:47,800
kuwa na manufaa?

810
00:43:47,800 --> 00:43:50,660
>> SPIKA 1: Ni inategemea mazingira yako.

811
00:43:50,660 --> 00:43:57,420
Hivyo kwa baadhi ya nadharia,
kama wewe ni kufanya kazi with-- OK,

812
00:43:57,420 --> 00:44:02,750
napenda kuona kama kuna mmoja manufaa
kwamba ni manufaa kwa zaidi ya nje

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

814
00:44:05,420 --> 00:44:15,780
Na mwingi, wakati wowote unahitaji
kuweka wimbo wa kitu ambacho

815
00:44:15,780 --> 00:44:20,456
ni hivi karibuni aliongeza ni wakati
wewe kwenda wanataka kutumia stack.

816
00:44:20,456 --> 00:44:24,770
>> Na siwezi kufikiria nzuri
mfano wa kwamba hivi sasa.

817
00:44:24,770 --> 00:44:29,955
Lakini, wakati hivi karibuni
Jambo muhimu zaidi na wewe,

818
00:44:29,955 --> 00:44:31,705
hiyo wakati stack
ni kwenda kuwa na manufaa.

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

820
00:44:35,797 --> 00:44:39,330
Mimi nina kujaribu kufikiri kama
kuna moja nzuri kwa ajili ya hii.

821
00:44:39,330 --> 00:44:43,720
Kama mimi nadhani wa mfano mzuri katika ijayo
Dakika 20, mimi dhahiri kukuambia.

822
00:44:43,720 --> 00:44:49,455
>> Lakini kwa ujumla, kama kuna kitu chochote,
kama nilivyosema zaidi, ambapo hivi karibuni

823
00:44:49,455 --> 00:44:52,470
ni muhimu zaidi, kwamba
ambapo stack anakuja katika kucheza.

824
00:44:52,470 --> 00:44:58,860
Wakati foleni ni aina ya kinyume.

825
00:44:58,860 --> 00:44:59,870
Na mbwa wote kidogo.

826
00:44:59,870 --> 00:45:00,890
Je, huyu si kubwa, haki?

827
00:45:00,890 --> 00:45:03,299
Najisikia kama mimi lazima
tu Bunny video

828
00:45:03,299 --> 00:45:05,090
haki ya katikati ya
sehemu kwa ajili ya guys

829
00:45:05,090 --> 00:45:08,870
sababu hii ni sehemu makali.

830
00:45:08,870 --> 00:45:10,480
>> Hivyo foleni.

831
00:45:10,480 --> 00:45:12,710
Kimsingi foleni ni kama mstari.

832
00:45:12,710 --> 00:45:15,780
You guys mimi nina uhakika kama hii ya matumizi ya kila siku,
tu kama katika dining kumbi zetu.

833
00:45:15,780 --> 00:45:18,160
Hivyo tuna kwenda katika
na kupata trays yetu, mimi nina

834
00:45:18,160 --> 00:45:21,260
kuhakikisha una kusubiri katika mstari
swipe au kupata chakula.

835
00:45:21,260 --> 00:45:24,650
>> Hivyo tofauti hapa
ni kwamba hii ni FIFO.

836
00:45:24,650 --> 00:45:30,090
Hivyo kama LIFO kwa mara ya mwisho katika, kwanza
nje, FIFO ni ya kwanza katika, nje ya kwanza.

837
00:45:30,090 --> 00:45:33,400
Hivyo hii ni ambapo chochote kuweka
juu ya kwanza ni yako muhimu.

838
00:45:33,400 --> 00:45:35,540
Hivyo kama wewe walikuwa wakisubiri
katika line-- unaweza you

839
00:45:35,540 --> 00:45:39,130
kufikiria kama wewe akaenda
kwenda kupata iPhone mpya

840
00:45:39,130 --> 00:45:42,800
na ilikuwa stack ambapo
Mtu wa mwisho katika mstari got ni ya kwanza,

841
00:45:42,800 --> 00:45:44,160
watu bila kuua kila mmoja.

842
00:45:44,160 --> 00:45:49,800
>> Hivyo FIFO, tuko wote familiar sana
na katika ulimwengu wa kweli hapa,

843
00:45:49,800 --> 00:45:54,930
na yote ina nini na kweli
aina ya recreating mstari huu nzima

844
00:45:54,930 --> 00:45:56,900
na kupanga foleni muundo.

845
00:45:56,900 --> 00:46:02,390
Hivyo ambapo pamoja na stack,
tuna kushinikiza na pop.

846
00:46:02,390 --> 00:46:06,440
Na foleni, tuna
enqueue na dequeue.

847
00:46:06,440 --> 00:46:10,910
Hivyo enqueue kimsingi ina maana
kuiweka kwenye nyuma,

848
00:46:10,910 --> 00:46:13,680
na njia dequeue kuchukua
mbali kutoka mbele.

849
00:46:13,680 --> 00:46:18,680
Hivyo mfumo wetu data ni
kidogo ngumu zaidi.

850
00:46:18,680 --> 00:46:21,060
Tuna jambo la pili kwa kuweka wimbo wa.

851
00:46:21,060 --> 00:46:25,950
>> Hivyo bila kichwa, hii
ni hasa stack, haki?

852
00:46:25,950 --> 00:46:27,900
Hii ni muundo sawa na stack.

853
00:46:27,900 --> 00:46:32,480
Kitu pekee tofauti na sasa ni sisi
kichwa hii, ambayo unafikiri nini

854
00:46:32,480 --> 00:46:34,272
ni kwenda kuweka wimbo wa?

855
00:46:34,272 --> 00:46:35,510
>> Watazamaji: moja ya kwanza.

856
00:46:35,510 --> 00:46:38,685
>> SPIKA 1: Haki,
Jambo la kwanza kwamba sisi kuweka katika.

857
00:46:38,685 --> 00:46:41,130
mkuu wa foleni yetu.

858
00:46:41,130 --> 00:46:42,240
Yeyote ni ya kwanza katika mstari.

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

860
00:46:45,300 --> 00:46:49,420
Haki wote, hivyo kama sisi kufanya enqueue.

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

862
00:46:52,720 --> 00:46:55,920
Tena, na yoyote ya
hizi miundo data,

863
00:46:55,920 --> 00:46:59,760
tangu sisi ni kushughulika na safu,
sisi haja ya kuangalia kama tuna nafasi.

864
00:46:59,760 --> 00:47:03,290
>> Hii ni aina ya kama mimi kuwaambia
nyie, kama wewe kufungua faili,

865
00:47:03,290 --> 00:47:04,760
unahitaji kuangalia kwa null.

866
00:47:04,760 --> 00:47:08,330
Na yoyote ya hizi mwingi
na foleni, unahitaji

867
00:47:08,330 --> 00:47:13,420
kuona kama kuna nafasi kwa sababu sisi ni
kushughulika na fasta ukubwa safu,

868
00:47:13,420 --> 00:47:16,030
kama sisi kuona here-- 0, 1 yote hadi 5.

869
00:47:16,030 --> 00:47:20,690
Hivyo kile sisi kufanya katika kesi hiyo ni kuangalia
kuona kama bado tuna nafasi.

870
00:47:20,690 --> 00:47:23,110
Ni kawaida yetu chini ya uwezo?

871
00:47:23,110 --> 00:47:28,480
>> Kama ni hivyo, tunahitaji kuhifadhi katika
mkia na sisi update kawaida yetu.

872
00:47:28,480 --> 00:47:30,250
Hivyo nini kinaweza kuwa mkia katika kesi hii?

873
00:47:30,250 --> 00:47:32,360
Ni si wazi imeandikwa nje.

874
00:47:32,360 --> 00:47:33,380
Jinsi gani sisi kuhifadhi?

875
00:47:33,380 --> 00:47:34,928
Gani mkia kuwa?

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

877
00:47:38,600 --> 00:47:40,190
>> Basi hebu kutembea kwa njia ya mfano huu.

878
00:47:40,190 --> 00:47:44,590
Hivyo hii ni safu ya ukubwa 6, haki?

879
00:47:44,590 --> 00:47:49,220
Na tuna haki ya sasa, kawaida yetu ni 5.

880
00:47:49,220 --> 00:47:55,240
Na wakati sisi kuweka katika, ni kwenda
kwenda katika tano ripoti, haki?

881
00:47:55,240 --> 00:47:57,030
Hivyo kuhifadhi katika mkia.

882
00:47:57,030 --> 00:48:05,600
>> Njia nyingine ya kuandika mkia ingekuwa tu
kuwa safu yetu ya ripoti ya ukubwa, haki?

883
00:48:05,600 --> 00:48:07,560
Hii ni kawaida 5.

884
00:48:07,560 --> 00:48:11,490
Jambo la pili ni kwenda kwenda katika 5.

885
00:48:11,490 --> 00:48:12,296
Baridi?

886
00:48:12,296 --> 00:48:13,290
OK.

887
00:48:13,290 --> 00:48:16,350
Ni anapata kidogo ngumu zaidi
wakati sisi kuanza messing na kichwa.

888
00:48:16,350 --> 00:48:17,060
Ndiyo?

889
00:48:17,060 --> 00:48:20,090
>> Watazamaji: Je, hiyo inamaanisha kwamba sisi
ingekuwa alitangaza safu kwamba

890
00:48:20,090 --> 00:48:23,880
ilikuwa vipengele tano kwa muda mrefu na
basi tuko kuongeza kwenye hilo?

891
00:48:23,880 --> 00:48:24,730
>> SPIKA 1: Hapana

892
00:48:24,730 --> 00:48:27,560
Hivyo katika kesi hii, hii ni stack.

893
00:48:27,560 --> 00:48:31,760
Hii itakuwa alitangaza
kama safu ya ukubwa 6.

894
00:48:31,760 --> 00:48:37,120
Na katika kesi hii, sisi
tu moja nafasi kushoto.

895
00:48:37,120 --> 00:48:42,720
>> OK, hivyo jambo moja ni katika hii
kesi, kama kichwa yetu ni saa 0,

896
00:48:42,720 --> 00:48:45,270
kisha sisi tu inaweza kuongeza yake katika kawaida.

897
00:48:45,270 --> 00:48:51,020
Lakini anapata trickier kidogo
kwa sababu kwa kweli, wao

898
00:48:51,020 --> 00:48:52,840
hawana slide
kwa hili, hivyo mimi nina kwenda

899
00:48:52,840 --> 00:48:56,670
kuteka moja kwa sababu si
kabisa kuwa rahisi mara moja

900
00:48:56,670 --> 00:48:59,230
kuanza kupata kuondoa mambo.

901
00:48:59,230 --> 00:49:03,920
Hivyo ambapo pamoja na stack
wewe tu milele kuwa

902
00:49:03,920 --> 00:49:08,920
na wasiwasi kuhusu kile kawaida ni
wakati wewe ni kuongeza kitu kwenye,

903
00:49:08,920 --> 00:49:15,710
na foleni pia unahitaji kufanya
kuhakikisha kwamba kichwa yako ni waliendelea kwa,

904
00:49:15,710 --> 00:49:20,760
kwa sababu jambo zuri kuhusu foleni
ni kwamba kama wewe si katika uwezo,

905
00:49:20,760 --> 00:49:23,040
unaweza kweli kufanya hivyo wrap kuzunguka.

906
00:49:23,040 --> 00:49:28,810
>> OK, hivyo moja thing-- oh,
hii ni chaki kutisha.

907
00:49:28,810 --> 00:49:31,815
Jambo moja kufikiria ni kesi.

908
00:49:31,815 --> 00:49:35,514

909
00:49:35,514 --> 00:49:37,140
Tutaweza tu kufanya mitano.

910
00:49:37,140 --> 00:49:41,810
OK, hivyo tunakwenda
kusema kichwa ni hapa.

911
00:49:41,810 --> 00:49:46,140
Hii ni 0, 1, 2, 3, 4.

912
00:49:46,140 --> 00:49:54,210
>> kichwa huko, na
tafadhali kuwa na mambo yao.

913
00:49:54,210 --> 00:49:58,340
Na tunataka kuongeza kitu katika, haki?

914
00:49:58,340 --> 00:50:01,170
Hivyo kitu kwamba tunahitaji
kujua ni kwamba kichwa daima

915
00:50:01,170 --> 00:50:05,620
kwenda kwa hoja kwa njia hii na
kisha kitanzi nyuma kote, sawa?

916
00:50:05,620 --> 00:50:10,190
>> Hivyo foleni hii ina nafasi, haki?

917
00:50:10,190 --> 00:50:13,950
Ina nafasi katika mwanzo,
aina ya kinyume ya hii.

918
00:50:13,950 --> 00:50:17,920
Hivyo kile sisi haja ya kufanya ni sisi
haja ya mahesabu ya mkia.

919
00:50:17,920 --> 00:50:20,530
Kama unajua kwamba yako
kichwa hana wakiongozwa, mkia

920
00:50:20,530 --> 00:50:24,630
ni tu safu yako katika
ripoti ya kawaida.

921
00:50:24,630 --> 00:50:30,000
>> Lakini katika hali halisi, kama wewe ni kutumia foleni,
kichwa yako ni pengine kuwa updated.

922
00:50:30,000 --> 00:50:33,890
Hivyo nini unahitaji kufanya ni
kweli mahesabu ya mkia.

923
00:50:33,890 --> 00:50:39,990
Hivyo kile sisi kufanya ni utaratibu huu
hapa, ambayo mimi nina kwenda basi wewe

924
00:50:39,990 --> 00:50:42,680
guys kufikiri juu, na
kisha tutaweza majadiliano juu yake.

925
00:50:42,680 --> 00:50:49,567

926
00:50:49,567 --> 00:50:50,400
Hivyo hii ni uwezo.

927
00:50:50,400 --> 00:50:55,890

928
00:50:55,890 --> 00:50:59,660
>> Hivyo hii itakuwa kweli
kukupa njia ya kufanya hivyo.

929
00:50:59,660 --> 00:51:03,205

930
00:51:03,205 --> 00:51:04,330
Kwa sababu katika kesi hii, ni nini?

931
00:51:04,330 --> 00:51:09,205
Kichwa yetu ni saa 1, ukubwa wetu ni 4.

932
00:51:09,205 --> 00:51:11,760

933
00:51:11,760 --> 00:51:18,490
Kama sisi Mod kwamba kwa 5, sisi kupata 0,
ambayo ni ambapo sisi lazima pembejeo yake.

934
00:51:18,490 --> 00:51:23,320

935
00:51:23,320 --> 00:51:26,080
>> Hivyo basi katika kesi ya pili,
kama tulikuwa kufanya hivyo,

936
00:51:26,080 --> 00:51:33,390
sisi kusema, sawa, hebu dequeue kitu.

937
00:51:33,390 --> 00:51:34,390
Sisi dequeue hii.

938
00:51:34,390 --> 00:51:37,740
Sisi kuchukua nje kipengele hii, haki?

939
00:51:37,740 --> 00:51:47,930
>> Na sasa kichwa yetu ni akizungumzia hapa,
na tunataka kuongeza katika kitu kingine.

940
00:51:47,930 --> 00:51:52,470
Hii ni kimsingi
nyuma ya mstari wetu, haki?

941
00:51:52,470 --> 00:51:55,450
Foleni unaweza wrap kuzunguka safu.

942
00:51:55,450 --> 00:51:57,310
Hiyo ni moja ya tofauti kubwa.

943
00:51:57,310 --> 00:51:58,780
Mwingi, huwezi kufanya hivyo.

944
00:51:58,780 --> 00:52:01,140
>> Na foleni, unaweza
sababu wote kwamba mambo

945
00:52:01,140 --> 00:52:03,940
ni kwamba unajua nini
ilikuwa hivi karibuni aliongeza.

946
00:52:03,940 --> 00:52:10,650
Tangu kila kitu kinaenda kuongezwa katika
mwelekeo huu leftward, katika kesi hii,

947
00:52:10,650 --> 00:52:16,480
na kisha wrap kuzunguka, unaweza
kuendelea kuweka katika mambo mapya

948
00:52:16,480 --> 00:52:18,830
mbele ya safu
sababu si kweli

949
00:52:18,830 --> 00:52:20,640
mbele ya safu tena.

950
00:52:20,640 --> 00:52:26,320
Unaweza kufikiri ya mwanzo ya
safu kama ambapo kichwa yako kweli ni.

951
00:52:26,320 --> 00:52:29,710
>> Hivyo formula hii ni jinsi
mahesabu ya mkia yako.

952
00:52:29,710 --> 00:52:32,780

953
00:52:32,780 --> 00:52:35,610
Je kwamba inafanya hisia?

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, na kisha
wewe guys kuwa dakika 10

957
00:52:44,040 --> 00:52:48,840
kuuliza mimi maswali yoyote inayoidhinisha
unataka, kwa sababu najua ni mambo.

958
00:52:48,840 --> 00:52:51,980
>> Haki wote, hivyo katika way-- sawa
Mimi sijui kama wewe guys niliona,

959
00:52:51,980 --> 00:52:53,450
lakini CS ni wote kuhusu mwelekeo.

960
00:52:53,450 --> 00:52:57,370
Mambo ni kiasi pretty
huo, tu na tweaks vidogo.

961
00:52:57,370 --> 00:52:58,950
Jambo hivyo sawa hapa.

962
00:52:58,950 --> 00:53:04,040
Tunahitaji kuangalia kuona kama sisi kweli
kuwa na kitu katika foleni yetu, haki?

963
00:53:04,040 --> 00:53:05,960
Kusema, sawa, ni kawaida yetu kubwa kuliko 0?

964
00:53:05,960 --> 00:53:06,730
Baridi.

965
00:53:06,730 --> 00:53:10,690
>> Kama sisi kufanya, basi sisi hoja kichwa yetu, ambayo
ni nini mimi tu alionyesha hapa.

966
00:53:10,690 --> 00:53:13,870
Sisi update kichwa yetu kuwa moja zaidi.

967
00:53:13,870 --> 00:53:18,390
Na kisha sisi mapunguzo wetu
ukubwa na kurudi kipengele.

968
00:53:18,390 --> 00:53:21,000

969
00:53:21,000 --> 00:53:26,250
>> Kuna mengi zaidi ya saruji
kanuni ya study.cs50.net,

970
00:53:26,250 --> 00:53:29,440
na mimi sana kupendekeza kwenda
kwa njia hiyo kama una muda,

971
00:53:29,440 --> 00:53:30,980
hata kama ni tu Pseudo-kificho.

972
00:53:30,980 --> 00:53:35,980
Na kama wewe guys wanataka kuzungumza kupitia
kwamba na mimi moja kwa moja, tafadhali napenda

973
00:53:35,980 --> 00:53:37,500
kujua.

974
00:53:37,500 --> 00:53:38,770
Ningependa kuwa na furaha kwa.

975
00:53:38,770 --> 00:53:42,720
Miundo data, kama
wewe kuchukua CS 124, utasikia

976
00:53:42,720 --> 00:53:47,830
kujua kwamba miundo data kupata sana
furaha na hii ni mwanzo tu.

977
00:53:47,830 --> 00:53:50,350
>> Hivyo najua ni vigumu.

978
00:53:50,350 --> 00:53:51,300
Ni sawa.

979
00:53:51,300 --> 00:53:52,410
Sisi mapambano.

980
00:53:52,410 --> 00:53:53,630
Mimi bado kufanya.

981
00:53:53,630 --> 00:53:56,660
Hivyo si wasiwasi sana kuhusu hilo.

982
00:53:56,660 --> 00:54:02,390
>> Lakini hiyo ni kimsingi yako
ajali shaka katika miundo data.

983
00:54:02,390 --> 00:54:03,400
Najua ni mengi.

984
00:54:03,400 --> 00:54:06,860
Je, kuna chochote kwamba sisi
ungependa kwenda tena?

985
00:54:06,860 --> 00:54:09,400
Chochote tunataka kuzungumza kupitia?

986
00:54:09,400 --> 00:54:10,060
Ndiyo?

987
00:54:10,060 --> 00:54:16,525
>> Watazamaji: Kwa mfano kwamba, hivyo
mkia mpya ni katika 0 juu ya kwamba?

988
00:54:16,525 --> 00:54:17,150
SPIKA 1: Ndiyo.

989
00:54:17,150 --> 00:54:18,230
Watazamaji: OK.

990
00:54:18,230 --> 00:54:24,220
Hivyo basi kwenda kupitia,
wewe d kuwa 1 plus 4 or--

991
00:54:24,220 --> 00:54:27,671
>> SPIKA 1: Hivyo wewe walikuwa wakisema,
wakati tunataka kwenda kufanya hii tena?

992
00:54:27,671 --> 00:54:28,296
Watazamaji: Yeah.

993
00:54:28,296 --> 00:54:38,290
Hivyo kama wewe walikuwa kuhesabia out-- ambapo ni
you kuhesabu mkia kutoka katika hilo?

994
00:54:38,290 --> 00:54:44,260
>> SPIKA 1: Hivyo mkia
ilikuwa in-- mimi iliyopita hii.

995
00:54:44,260 --> 00:54:52,010
Hivyo katika mfano huu hapa, hii ilikuwa
safu sisi tunataka, sawa?

996
00:54:52,010 --> 00:54:54,670
Hivyo tuna mambo katika 1, 2, 3 na 4.

997
00:54:54,670 --> 00:55:05,850
Hivyo tuna kichwa yetu ni sawa na 1 katika
hatua hii, na ukubwa wetu ni sawa na 4

998
00:55:05,850 --> 00:55:07,050
katika hatua hii, haki?

999
00:55:07,050 --> 00:55:08,960
>> Wewe kukubaliana kwamba kesi?

1000
00:55:08,960 --> 00:55:14,620
Hivyo sisi kufanya kichwa plus kawaida, ambayo
inatupa 5, na kisha sisi Mod na 5.

1001
00:55:14,620 --> 00:55:20,690
Sisi kupata 0, ambayo inatuambia kwamba ni 0
ambapo ni mkia yetu, ambapo tuna nafasi.

1002
00:55:20,690 --> 00:55:22,010
>> Watazamaji: Nini kofia?

1003
00:55:22,010 --> 00:55:23,520
>> SPIKA 1: uwezo.

1004
00:55:23,520 --> 00:55:24,020
Pole.

1005
00:55:24,020 --> 00:55:29,640
Hivyo kwamba ni ukubwa wa safu yako.

1006
00:55:29,640 --> 00:55:35,210

1007
00:55:35,210 --> 00:55:36,047
Ndiyo?

1008
00:55:36,047 --> 00:55:39,210
>> Watazamaji: [inaudible] kabla ya
sisi kurudi kipengele?

1009
00:55:39,210 --> 00:55:46,270
>> SPIKA 1: Hivyo sisi hoja
kichwa au kurudi sasa?

1010
00:55:46,270 --> 00:55:52,680
Hivyo kama sisi hoja moja, mapunguzo kawaida?

1011
00:55:52,680 --> 00:55:54,150
Kushikilia.

1012
00:55:54,150 --> 00:55:55,770
Mimi dhahiri alisahau nyingine.

1013
00:55:55,770 --> 00:56:00,646

1014
00:56:00,646 --> 00:56:01,990
Kamwe akili.

1015
00:56:01,990 --> 00:56:04,980
Kuna si formula nyingine.

1016
00:56:04,980 --> 00:56:09,980
Yeah, wewe unataka kurudi
kichwa na kisha kuondoka nyuma.

1017
00:56:09,980 --> 00:56:13,270
>> Watazamaji: sawa, kwa sababu Katika hii
uhakika, kichwani ilikuwa saa 0,

1018
00:56:13,270 --> 00:56:18,452
na kisha unataka kurudi
index 0 na kisha kufanya kichwa 1?

1019
00:56:18,452 --> 00:56:19,870
>> SPIKA 1: Haki.

1020
00:56:19,870 --> 00:56:22,820
Nadhani kuna mwingine
formula aina ya kama hii.

1021
00:56:22,820 --> 00:56:26,970
Sina ni juu ya kichwa yangu kama
Sitaki kukupa moja sahihi.

1022
00:56:26,970 --> 00:56:35,470
Lakini nadhani ni kikamilifu halali kwa
kusema, sawa, kuhifadhi element-- hii chochote

1023
00:56:35,470 --> 00:56:40,759
kipengele kichwa ya is-- mapunguzo yako
ukubwa, hoja ya kichwa yako juu, na kurudi

1024
00:56:40,759 --> 00:56:41,800
chochote kwamba kipengele ni.

1025
00:56:41,800 --> 00:56:44,760
Hiyo ni kikamilifu halali.

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
Najisikia kama hii si
kama most-- wewe si

1029
00:56:53,560 --> 00:56:55,740
kwenda kutembea nje ya hapa
kama, ndiyo, najua anajaribu.

1030
00:56:55,740 --> 00:56:56,880
I got yote.

1031
00:56:56,880 --> 00:56:57,670
Hiyo ni sawa.

1032
00:56:57,670 --> 00:57:00,200
Mimi ahadi.

1033
00:57:00,200 --> 00:57:05,240
Lakini miundo data ni kitu ambacho
inachukua muda mwingi kupata kutumika.

1034
00:57:05,240 --> 00:57:10,010
Pengine ni moja ya gumu
mambo, nadhani, katika shaka.

1035
00:57:10,010 --> 00:57:15,330
>> Hivyo ni dhahiri inachukua
marudio na kuangalia at-- mimi

1036
00:57:15,330 --> 00:57:20,050
hawakuwa kweli kujua orodha wanaohusishwa
mpaka mimi mno pamoja nao,

1037
00:57:20,050 --> 00:57:22,550
katika njia sawa kwamba sikuwa
kweli kuelewa kuyatumia

1038
00:57:22,550 --> 00:57:27,040
mpaka nimepata kufundisha kwa ajili ya mbili
miaka na kufanya psets yangu mwenyewe kwa hayo.

1039
00:57:27,040 --> 00:57:28,990
Inachukua mengi ya kikariri na wakati.

1040
00:57:28,990 --> 00:57:32,600
Na hatimaye, itakuwa aina ya click.

1041
00:57:32,600 --> 00:57:36,320
>> Lakini wakati huo huo, kama una aina
ya kiwango cha juu ya uelewa wa nini

1042
00:57:36,320 --> 00:57:39,321
hizi kufanya, faida yao
na cons-- ambayo ni nini

1043
00:57:39,321 --> 00:57:41,820
sisi kweli huwa na kusisitiza,
hasa katika mwendo intro.

1044
00:57:41,820 --> 00:57:45,511
Kama, kwa nini sisi kutumia
a kujaribu juu ya safu?

1045
00:57:45,511 --> 00:57:48,010
Kama, nini ni chanya
na hasi ya kila mmoja wa wale?

1046
00:57:48,010 --> 00:57:51,610
>> Na kuelewa biashara awamu ya pili
kati ya kila ya miundo haya

1047
00:57:51,610 --> 00:57:54,910
ni nini muhimu zaidi hivi sasa.

1048
00:57:54,910 --> 00:57:58,140
Kuna inaweza kuwa moja mambo
swali au mbili kwamba

1049
00:57:58,140 --> 00:58:03,710
kwenda kuuliza wewe kutekeleza kushinikiza au
kutekeleza pop au enqueue na dequeue.

1050
00:58:03,710 --> 00:58:07,340
Lakini kwa sehemu kubwa, kuwa na kwamba
kiwango cha juu ufahamu na zaidi

1051
00:58:07,340 --> 00:58:09,710
ya kufahamu Intuitive ni
muhimu zaidi kuliko kweli

1052
00:58:09,710 --> 00:58:11,250
kuwa na uwezo wa kutekeleza.

1053
00:58:11,250 --> 00:58:14,880
>> Ni d kuwa kweli kutisha kama nyote
inaweza kwenda nje na kwenda kutekeleza kujaribu,

1054
00:58:14,880 --> 00:58:19,720
lakini sisi kuelewa ni si lazima
Jambo nzuri zaidi hivi sasa.

1055
00:58:19,720 --> 00:58:23,370
Lakini unaweza katika pset yako, kama unataka
kwa, na kisha utapata mazoezi,

1056
00:58:23,370 --> 00:58:27,200
na kisha labda utasikia
kweli kuelewa.

1057
00:58:27,200 --> 00:58:27,940
Ndiyo?

1058
00:58:27,940 --> 00:58:30,440
>> Watazamaji: OK, hivyo ambayo ndio ni
sisi maana ya kutumia katika pset?

1059
00:58:30,440 --> 00:58:31,916
Je, mimi haja ya kutumia mmoja wao?

1060
00:58:31,916 --> 00:58:32,540
SPIKA 1: Ndiyo.

1061
00:58:32,540 --> 00:58:34,199
Hivyo una uchaguzi wako.

1062
00:58:34,199 --> 00:58:36,740
Nadhani katika kesi hii, tunaweza
majadiliano juu ya pset kidogo

1063
00:58:36,740 --> 00:58:40,480
kwa sababu mimi mbio kupitia hizi.

1064
00:58:40,480 --> 00:58:47,779
Hivyo katika pset yako, una yako
uchaguzi wa inajaribu au meza hash.

1065
00:58:47,779 --> 00:58:49,570
Baadhi ya watu kujaribu
na kutumia filters Bloom,

1066
00:58:49,570 --> 00:58:51,840
lakini wale kitaalam si sahihi.

1067
00:58:51,840 --> 00:58:55,804
Kwa sababu ya asili yao ya kubahatisha,
wao kutoa chanya uongo wakati mwingine.

1068
00:58:55,804 --> 00:58:57,095
Wao ni baridi kuangalia katika, ingawa.

1069
00:58:57,095 --> 00:58:59,030
Sana kupendekeza kuangalia
yao angalau.

1070
00:58:59,030 --> 00:59:03,260
Lakini una uchaguzi wako
kati ya hash meza na kujaribu.

1071
00:59:03,260 --> 00:59:06,660
Na kwamba kinaendelea kuwa ambapo
mzigo katika kamusi yako.

1072
00:59:06,660 --> 00:59:09,230
>> Na wewe utakuwa haja ya kuchagua
hash kazi yako,

1073
00:59:09,230 --> 00:59:13,420
itabidi kuchagua jinsi wengi
ndoo una, na itakuwa kutofautiana.

1074
00:59:13,420 --> 00:59:17,440
Kama kama una ndoo zaidi,
labda itabidi kukimbia kwa kasi.

1075
00:59:17,440 --> 00:59:22,790
Lakini labda wewe ni kupoteza
mengi ya nafasi ya kuwa njia, ingawa.

1076
00:59:22,790 --> 00:59:26,320
Una takwimu ni nje.

1077
00:59:26,320 --> 00:59:27,140
Mmhmm?

1078
00:59:27,140 --> 00:59:29,875
>> Watazamaji: Ulisema kabla kwamba
tunaweza kutumia kazi nyingine hash,

1079
00:59:29,875 --> 00:59:31,750
kwamba hatuna kwa
kujenga hash kazi?

1080
00:59:31,750 --> 00:59:32,666
>> SPIKA 1: Ndiyo, haki.

1081
00:59:32,666 --> 00:59:38,150
Hivyo literally kwa hash kazi yako,
kama google "hash"

1082
00:59:38,150 --> 00:59:40,770
na kuangalia kwa baadhi ya wale baridi.

1083
00:59:40,770 --> 00:59:43,250
Wewe si inatarajiwa kujenga
hash yako mwenyewe kazi.

1084
00:59:43,250 --> 00:59:46,100
Watu kutumia yao
Theses juu ya mambo haya.

1085
00:59:46,100 --> 00:59:50,250
>> Hivyo msiwe na wasiwasi kuhusu kujenga yako mwenyewe.

1086
00:59:50,250 --> 00:59:53,350
Kupata moja online kuanza na.

1087
00:59:53,350 --> 00:59:56,120
Baadhi yao una
kuendesha kidogo

1088
00:59:56,120 --> 00:59:59,430
kuhakikisha aina ya kurudi mechi ya juu
na whatnot, hivyo katika mwanzo,

1089
00:59:59,430 --> 01:00:02,420
Ningependa kupendekeza kutumia kitu
kweli rahisi kwamba labda tu

1090
01:00:02,420 --> 01:00:04,680
hashes juu ya barua ya kwanza.

1091
01:00:04,680 --> 01:00:08,760
Na kisha mara moja una kwamba kazi,
kuchanganya baridi hash kazi.

1092
01:00:08,760 --> 01:00:09,260
Mmhmm?

1093
01:00:09,260 --> 01:00:13,020
>> Watazamaji: Je kujaribu kuwa au
ufanisi lakini vigumu tu, like--

1094
01:00:13,020 --> 01:00:15,880
>> SPIKA 1: Hivyo kujaribu, nadhani,
ni intuitively ngumu kutekeleza

1095
01:00:15,880 --> 01:00:18,310
lakini ni haraka sana.

1096
01:00:18,310 --> 01:00:20,620
Hata hivyo, inachukua hadi nafasi zaidi.

1097
01:00:20,620 --> 01:00:25,270
Tena, unaweza kuongeza wote wawili wa wale walio katika
njia tofauti na kuna njia to--

1098
01:00:25,270 --> 01:00:26,770
Watazamaji: Jinsi ni sisi graded juu ya hili?

1099
01:00:26,770 --> 01:00:27,540
Je, ni matter--

1100
01:00:27,540 --> 01:00:29,164
>> SPIKA 1: Hivyo wewe ni hadhi njia ya kawaida.

1101
01:00:29,164 --> 01:00:31,330
Wewe ni kwenda kuwa na hadhi ya kubuni.

1102
01:00:31,330 --> 01:00:36,020
Njia yoyote ya kufanya, unataka
kuhakikisha ni kama kifahari kama inaweza kuwa

1103
01:00:36,020 --> 01:00:38,610
na kama ufanisi kama inaweza kuwa.

1104
01:00:38,610 --> 01:00:41,950
Lakini kama wewe kuchagua kujaribu au hash
meza, kwa muda mrefu kama ni kazi,

1105
01:00:41,950 --> 01:00:45,350
sisi ni furaha na kwamba.

1106
01:00:45,350 --> 01:00:48,370
Na kama wewe kutumia kitu ambacho hashes
juu ya barua ya kwanza, hiyo ni nzuri,

1107
01:00:48,370 --> 01:00:51,410
kama labda kama kubuni-busara.

1108
01:00:51,410 --> 01:00:53,410
Sisi ni pia kufikia
hatua katika semester-- hii

1109
01:00:53,410 --> 01:00:55,340
Sijui kama
guys noticed-- kama wewe ni

1110
01:00:55,340 --> 01:00:58,780
pset darasa kushuka kidogo
kwa sababu ya kubuni na whatnot,

1111
01:00:58,780 --> 01:00:59,900
hiyo ni kikamilifu faini.

1112
01:00:59,900 --> 01:01:02,960
Ni kupata kwa uhakika ambapo yako
programu ni kupata ngumu zaidi.

1113
01:01:02,960 --> 01:01:04,830
Kuna maeneo zaidi
unaweza kuboresha.

1114
01:01:04,830 --> 01:01:06,370
>> Hivyo ni kawaida kabisa.

1115
01:01:06,370 --> 01:01:08,810
Siyo kwamba wewe ni
kufanya mbaya zaidi juu ya pset yako.

1116
01:01:08,810 --> 01:01:11,885
Ni tu sisi ni kuwa vigumu wewe sasa.

1117
01:01:11,885 --> 01:01:13,732
Hivyo kila mtu ni hisia yake.

1118
01:01:13,732 --> 01:01:14,940
Mimi tu graded psets yako yote.

1119
01:01:14,940 --> 01:01:16,490
Najua kila mtu ni hisia yake.

1120
01:01:16,490 --> 01:01:19,600
>> Hivyo si kuwa na wasiwasi juu ya hilo.

1121
01:01:19,600 --> 01:01:23,580
Na kama una maswali yoyote kuhusu
psets kabla au njia unaweza kuboresha,

1122
01:01:23,580 --> 01:01:27,760
Mimi kujaribu na kutoa maoni maalum
maeneo, lakini wakati mwingine ni marehemu

1123
01:01:27,760 --> 01:01:30,840
na mimi kupata kuchoka.

1124
01:01:30,840 --> 01:01:34,885
Je, kuna mambo mengine yoyote
kuhusu data miundo?

1125
01:01:34,885 --> 01:01:37,510
Mimi nina uhakika wewe guys si kweli
wanataka kuzungumza kuhusu wao tena,

1126
01:01:37,510 --> 01:01:42,650
lakini kama kuna, mimi nina furaha
kwenda juu yao, kama vile kitu chochote

1127
01:01:42,650 --> 01:01:45,580
kutoka hotuba ya zamani hii
wiki au wiki iliyopita.

1128
01:01:45,580 --> 01:01:51,580
>> Najua wiki iliyopita alikuwa mapitio wote, hivyo
sisi inaweza kuwa skipped juu ya baadhi ya mapitio

1129
01:01:51,580 --> 01:01:54,190
kutoka mihadhara.

1130
01:01:54,190 --> 01:01:58,230
Maswali mengine yoyote naweza kujibu?

1131
01:01:58,230 --> 01:01:59,350
OK, haki ya wote.

1132
01:01:59,350 --> 01:02:02,400
Naam, wewe guys kupata nje ya dakika 15 mapema.

1133
01:02:02,400 --> 01:02:08,370
>> Natumaini hii ilikuwa nusu kusaidia angalau,
na mimi kuona wewe guys wiki ijayo,

1134
01:02:08,370 --> 01:02:12,150
au Alhamisi ofisi masaa.

1135
01:02:12,150 --> 01:02:15,285
Je, kuna maombi kwa vitafunio
kwa wiki ijayo, ni jambo?

1136
01:02:15,285 --> 01:02:17,459
Kwa sababu mimi alisahau pipi leo.

1137
01:02:17,459 --> 01:02:19,750
Na mimi kuletwa pipi mwisho
wiki, lakini ilikuwa Columbus Day,

1138
01:02:19,750 --> 01:02:25,400
hivyo kulikuwa na kama watu sita ambao
alikuwa mifuko minne ya pipi kwa wenyewe.

1139
01:02:25,400 --> 01:02:28,820
Mimi inaweza kuleta Starbursts
tena kama wewe kama.

1140
01:02:28,820 --> 01:02:29,580
Starbursts?

1141
01:02:29,580 --> 01:02:32,250
OK, sauti nzuri.

1142
01:02:32,250 --> 01:02:35,050
Kuwa na siku kubwa, guys.

1143
01:02:35,050 --> 01:02:39,510