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>> [Halisi kucheza]

3
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DAVID Malan: zote haki.

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00:00:13,500 --> 00:00:14,670
Haki wote, kuwakaribisha nyuma.

5
00:00:14,670 --> 00:00:18,120
Hivyo hii ni wiki ya 4, mwanzo
yake, tayari.

6
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Na itabidi kukumbuka kwamba wiki iliyopita, sisi kuweka
Kanuni kando kwa ajili ya kidogo kidogo tu

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na sisi kuanza kuzungumza zaidi kidogo
ngazi ya juu, juu ya mambo kama

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kutafuta na kuchagua, ingawa
kiasi fulani rahisi mawazo, ni

9
00:00:28,130 --> 00:00:31,840
mwakilishi wa darasa la matatizo
utaanza kutatua hasa

10
00:00:31,840 --> 00:00:34,820
kama wewe kuanza kufikiri juu ya mwisho
miradi na ufumbuzi kuvutia

11
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wanaweza kuwa na matatizo halisi ya dunia.

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Sasa Bubble aina alikuwa mmoja wa rahisi
vile algorithms, na ni

13
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kazi kwa kuwa na namba hizi ndogo
katika orodha au katika safu ya aina

14
00:00:42,900 --> 00:00:46,530
Bubble njia yao hadi juu, na
idadi kubwa hoja njia yao chini

15
00:00:46,530 --> 00:00:47,930
mwisho wa orodha hiyo.

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>> Na kukumbuka kwamba tunaweza taswira
Bubble aina kidogo

17
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kitu kama hiki.

18
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Hivyo basi mimi kwenda mbele na bonyeza Start.

19
00:00:53,640 --> 00:00:55,350
Nimekuwa preselected Bubble aina.

20
00:00:55,350 --> 00:00:58,920
Na kama wewe kukumbuka kuwa bluu mirefu
mistari kuwakilisha idadi kubwa, ndogo

21
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mistari ya bluu kuwakilisha idadi ndogo, kama
sisi kwenda kwa njia hii tena na tena na

22
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tena, kulinganisha baa mbili karibu na kila
nyingine katika nyekundu, tunakwenda wabadilishane

23
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kubwa na ndogo kama
wao ni nje ya utaratibu.

24
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>> Hivyo hii kwenda juu na kwenda juu na kwenda
juu, na utaona kuwa kubwa

25
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mambo ni kufanya njia yao ya
haki, na mambo madogo ni

26
00:01:16,700 --> 00:01:17,900
kufanya njia yao ya kushoto.

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Lakini tulianza kupima
ufanisi,

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ubora wa algorithm hii.

29
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Na sisi alisema kwamba katika mbaya
kesi, algorithm hii alichukua

30
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takribani ngapi hatua?

31
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>> Hivyo n squared.

32
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Na nini ilikuwa n?

33
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>> Watazamaji: Idadi ya vipengele.

34
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>> DAVID Malan: Hivyo n mara
idadi ya vipengele.

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Na hivyo tutaweza kufanya hili mara nyingi.

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Wakati wowote tunataka kuzungumza juu ya ukubwa
wa tatizo au ukubwa wa

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pembejeo, au kiasi cha muda inachukua
kuzalisha pato, tutaweza tu

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wa jumla chochote
pembejeo ni kama n.

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Hivyo nyuma katika Wiki 0, idadi ya kurasa
katika kitabu cha simu mara n.

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idadi ya wanafunzi
katika chumba ilikuwa n.

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Hivyo hapa, pia, sisi ni kufuatia
kwamba mfano.

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>> Sasa n squared si hasa
haraka, hivyo sisi alijaribu kufanya vizuri zaidi.

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Na hivyo sisi inaonekana katika michache ya
nyingine algorithms, kati ya ambayo

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walikuwa uteuzi aina.

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Hivyo uteuzi aina alikuwa
tofauti kidogo.

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Ilikuwa karibu rahisi, mimi kuthubutu kusema,
ambapo mimi kuanza saa ya kuanza

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orodha ya kujitolea wetu na mimi tu tena
na tena na tena safari kwa kupitia

48
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orodha, kukwanyua nje ndogo
kipengele katika muda na kuweka naye au

49
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yake katika mwanzo wa orodha.

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>> Lakini hii pia, mara sisi kuanza kufikiri
kupitia hesabu na kubwa

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picha, mawazo kuhusu ni mara ngapi
Mimi kwenda na kurudi nyuma na

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na nje, sisi alisema katika kesi mbaya,
uteuzi aina, pia, ilikuwa nini?

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n squared.

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Sasa katika ulimwengu wa kweli, ni nguvu
kweli kuwa kidogo kwa kasi zaidi.

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Sababu tena, sikuwa na kuweka
inafuatilia mara moja mimi alikuwa yamepangwa

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ndogo vipengele.

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Lakini kama sisi kufikiri juu ya n kubwa sana, na
kama wewe aina ya kufanya math nje kama

58
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Mimi alifanya juu ya bodi, na squared n
bala kitu, kila kitu kingine

59
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badala n squared, mara moja n
anapata kweli kubwa, haina

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kweli jambo kama mengi.

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Hivyo kama wanasayansi wa kompyuta, sisi aina ya
kugeuka vipofu ndogo

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mambo na lengo tu juu ya sababu katika
kujieleza kwamba kwenda kufanya

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tofauti kubwa.

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>> Naam, Mwisho, sisi inaonekana
katika aina kuingizwa.

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Na hii ilikuwa sawa katika roho, lakini
badala ya kwenda kwa njia ya iteratively na

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kuchagua ndogo kipengele moja katika
wakati, mimi badala yake akachukua mkono kwamba mimi

67
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alikuwa kushughulikiwa, na niliamua, kila
haki, wewe ni hapa.

68
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Kisha mimi alihamia kwenye kipengele ijayo
na kuamua kwamba yeye au

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yeye ni mali hapa.

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Na kisha mimi wakiongozwa na juu.

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Na mimi ili kwa, njiani,
kuhama guys haya ili

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kufanya chumba kwa ajili yao.

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Hivyo kwamba ilikuwa ni aina ya mabadiliko ya akili
wa aina uteuzi kwamba sisi

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kuitwa kuingizwa aina.

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>> Hivyo hizi mada kutokea
katika ulimwengu halisi.

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Miaka michache tu iliyopita, wakati fulani
seneta alikuwa akikimbia kwa rais,

77
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Eric Schmidt, wakati Mkurugenzi Mtendaji wa
Google, kwa kweli alikuwa na nafasi ya

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kuwahoji naye.

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Na sisi mawazo tunatarajia kushiriki hii YouTube
video kwa ajili yenu hapa, kama tunaweza kugeuka up

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kiasi.

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>> [Video avspelning]

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>> -Sasa, Seneta, uko hapa katika Google,
na mimi kama kufikiri ya urais

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kama mahojiano ya kazi.

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>> [Kicheko]

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>> -Sasa ni vigumu kupata
kazi kama rais.

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Na wewe ni kwenda kupitia
rigours sasa.

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Ni pia vigumu kupata kazi saa Google.

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Tuna maswali na tunaomba
yetu wagombea maswali.

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Na hii ni moja kutoka Larry Schwimmer.

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>> [Kicheko]

91
00:04:05,325 --> 00:04:06,400
-Wewe guys kufikiri mimi kidding?

92
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Ni haki hapa.

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Je, ni njia ya ufanisi zaidi kwa
kutatua milioni integers mbili kidogo?

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>> [Kicheko]

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>> -Naam, uh -

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>> Nina-pole.

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Labda sisi lazima -

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>> -Hapana, hapana, hapana, hapana, hapana.

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>> -Hiyo si -

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OK.

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>> -Nadhani aina Bubble ingekuwa
kuwa njia sahihi ya kwenda.

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>> [Kicheko]

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>> [Cheering na makofi]

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>> -Haya, ambaye alimwambia hii?

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OK.

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>> [MWISHO video avspelning]

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>> DAVID Malan: Hivyo kuna una hiyo.

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Hivyo tulianza kupima hizi mbio
nyakati, hivyo kusema, na kitu

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kuitwa asymptotic nukuu, ambayo ni
tu akimaanisha aina yetu ya kugeuka

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jicho kipofu kwa sababu hizo ndogo na
tu kuangalia wakati mbio,

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utendaji ya algorithms haya,
kama n kweli anapata kubwa zaidi ya muda.

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Na hivyo sisi ilianzisha kubwa O. Na kubwa O
kuwakilishwa kitu ambacho tulidhani

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ya kama amefungwa juu.

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Na kweli, Barry, tunaweza kupunguza
kuliko mic kidogo?

115
00:04:59,570 --> 00:05:01,040
>> Tulidhani ya hii ni amefungwa juu.

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Hivyo kubwa O ya njia n squared kwamba katika
kesi mbaya, kitu kama

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uteuzi aina bila kuchukua
n hatua squared.

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Au kitu kama aina ya kuingizwa
ingekuwa n hatua squared.

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Sasa kwa ajili ya kitu kama kuingizwa
aina, nini ilikuwa hali mbaya zaidi?

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Kutokana na safu, nini mbaya
iwezekanavyo scenario kwamba unaweza kupata

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mwenyewe wanakabiliwa na?

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00:05:20,650 --> 00:05:21,860
>> Ni kabisa nyuma, haki?

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Kwa sababu kama ni kabisa nyuma,
una kufanya mengi yote ya kazi.

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Kwa sababu kama wewe ni kabisa nyuma,
wewe ni kwenda kupata

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kubwa kipengele hapa, hata kama
ni mali ya chini huko.

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Hivyo wewe ni kwenda kusema, haki ya wote, katika
huu katika muda, wewe ni hapa,

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hivyo wewe kuondoka peke yake.

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>> Basi wewe kutambua, oh, damn, nina
hoja hii ya kipengele kidogo kidogo kwa

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kushoto wa wewe.

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Basi mimi na kwa kufanya hivyo tena
na tena na tena.

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Na kama mimi kutembea na kurudi, wewe
itakuwa aina ya kujisikia ya utendaji wa

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algorithm kwamba, kwa sababu mara kwa mara mimi
shuffling kila mtu mwingine chini katika

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safu kufanya chumba kwa ajili yake.

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Hivyo kwamba ni kesi mbaya.

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00:05:47,750 --> 00:05:48,570
>> Kwa upande mwingine -

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00:05:48,570 --> 00:05:50,320
na hii ilikuwa mwisho cliffhanger wakati -

137
00:05:50,320 --> 00:05:54,065
sisi alisema kwamba aina ya kuingizwa
mara omega ya nini?

138
00:05:54,065 --> 00:05:57,530
Nini mbio bora kesi
wakati wa aina kuingizwa?

139
00:05:57,530 --> 00:05:58,520
Hivyo ni kweli n.

140
00:05:58,520 --> 00:06:00,980
Hiyo ilikuwa tupu kwamba sisi kushoto
juu ya bodi ya mwisho wakati.

141
00:06:00,980 --> 00:06:03,160
>> Na ni omega ya n sababu kwa nini?

142
00:06:03,160 --> 00:06:06,630
Naam, katika kesi bora sana, nini
kuingizwa aina kwenda kuwa mitupu?

143
00:06:06,630 --> 00:06:09,830
Naam, orodha hiyo kabisa kutatuliwa
tayari, ndogo kazi ya kufanya.

144
00:06:09,830 --> 00:06:12,460
Lakini nini nadhifu kuhusu aina ya kuingizwa
ni kwamba kwa sababu ni kuanza hapa na

145
00:06:12,460 --> 00:06:15,340
anaamua, oh, wewe ni idadi
moja, wewe ni hapa.

146
00:06:15,340 --> 00:06:16,970
Oh, nini bahati nzuri.

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00:06:16,970 --> 00:06:17,740
>> Wewe ni namba mbili.

148
00:06:17,740 --> 00:06:19,030
Wewe pia ni mali hapa.

149
00:06:19,030 --> 00:06:21,010
Namba tatu, hata bora zaidi,
wewe ni hapa.

150
00:06:21,010 --> 00:06:25,210
Haraka kama anapata hadi mwisho wa
orodha, kwa kila aina ya kuingizwa pseudocode

151
00:06:25,210 --> 00:06:28,010
kwamba sisi kutembea kwa njia ya maneno
mara ya mwisho, ni kosa.

152
00:06:28,010 --> 00:06:32,790
Lakini uteuzi aina, kwa kulinganisha,
naendelea kufanya nini?

153
00:06:32,790 --> 00:06:35,260
>> Naendelea kwenda kupitia orodha
tena na tena na tena.

154
00:06:35,260 --> 00:06:39,160
Kwa sababu ufahamu muhimu kulikuwa tu
mara moja umefanya inaonekana njia yote ya

155
00:06:39,160 --> 00:06:42,500
mwisho wa orodha unaweza kuwa na uhakika
kwamba kipengele wewe kuchaguliwa mara

156
00:06:42,500 --> 00:06:45,560
kweli kipengele sasa madogo.

157
00:06:45,560 --> 00:06:48,920
Hivyo haya mbalimbali ya akili mifano mwisho
hadi kujitoa sana baadhi ya ulimwengu halisi

158
00:06:48,920 --> 00:06:53,130
tofauti kwa ajili yetu, kama vile hizi
kinadharia asymptotic tofauti.

159
00:06:53,130 --> 00:06:56,910
>> Hivyo tu kwa kurejea, basi, kubwa O ya n
squared, tumeona vile chache

160
00:06:56,910 --> 00:06:58,350
algorithms hivi sasa.

161
00:06:58,350 --> 00:06:59,580
Kubwa O ya n?

162
00:06:59,580 --> 00:07:02,870
Nini algorithm ambayo inaweza
kuwa alisema kuwa kubwa O ya n?

163
00:07:02,870 --> 00:07:06,930
Katika hali mbaya zaidi, inachukua
idadi linear ya hatua.

164
00:07:06,930 --> 00:07:07,810
>> OK, linear utafutaji.

165
00:07:07,810 --> 00:07:10,470
Na katika hali mbaya zaidi, ambapo ni
kipengele wewe ni kuangalia kwa wakati

166
00:07:10,470 --> 00:07:12,950
kutumia tafuta linear?

167
00:07:12,950 --> 00:07:14,680
>> OK, katika kesi mbaya,
ni hata huko.

168
00:07:14,680 --> 00:07:17,000
Au katika kesi ya pili mbaya zaidi, ni
njia yote katika mwisho, ambayo ni

169
00:07:17,000 --> 00:07:18,880
pamoja na-au-bala tofauti hatua moja.

170
00:07:18,880 --> 00:07:21,180
Hivyo mwisho wa siku,
tunaweza kusema ni linear.

171
00:07:21,180 --> 00:07:23,910
Kubwa O ya n itakuwa linear utafutaji,
kwa sababu katika hali mbaya zaidi,

172
00:07:23,910 --> 00:07:26,610
kipengele hata si huko au ni
njia yote mwishoni.

173
00:07:26,610 --> 00:07:29,370
>> Naam, kubwa O logi ya n.

174
00:07:29,370 --> 00:07:32,760
Hatukuwa majadiliano katika kina kubwa kuhusu
hii, lakini tumeona hii kabla.

175
00:07:32,760 --> 00:07:36,840
Nini anaendesha katika kinachojulikana logarithmic
wakati, katika kesi mbaya?

176
00:07:36,840 --> 00:07:38,500
>> Yeah, hivyo binary tafuta.

177
00:07:38,500 --> 00:07:42,930
Na kisha tafuta katika kesi mbaya
wanaweza kuwa na kipengele mahali fulani katika

178
00:07:42,930 --> 00:07:45,640
katikati, au mahali fulani
ndani ya safu.

179
00:07:45,640 --> 00:07:48,040
Lakini wewe tu kupata hiyo mara moja
kugawanya orodha katika nusu, katika

180
00:07:48,040 --> 00:07:48,940
nusu, katika nusu, katika nusu.

181
00:07:48,940 --> 00:07:50,200
Na kisha voila, ni huko.

182
00:07:50,200 --> 00:07:52,500
Au tena, kesi mbaya,
ni hata huko.

183
00:07:52,500 --> 00:07:56,770
Lakini huwezi kujua kwamba siyo kuna
mpaka aina ya kufikia mwisho

184
00:07:56,770 --> 00:08:00,470
chini-wengi vipengele na kupunguza nusu ya
na kupunguza nusu na nusu.

185
00:08:00,470 --> 00:08:01,400
>> Kubwa O ya 1.

186
00:08:01,400 --> 00:08:03,540
Hivyo tunaweza kubwa O ya 2, kubwa O ya 3.

187
00:08:03,540 --> 00:08:06,260
Wowote unataka tu ya simu mara kwa mara,
sisi tu ya aina ya tu kurahisisha

188
00:08:06,260 --> 00:08:07,280
kwamba kama kubwa O ya 1.

189
00:08:07,280 --> 00:08:10,440
Hata ingawa kama realistically, inachukua
2 au hata 100 hatua, ikiwa ni

190
00:08:10,440 --> 00:08:13,680
mara kwa mara ya simu ya hatua,
sisi tu kusema kubwa O ya 1.

191
00:08:13,680 --> 00:08:15,930
Nini algorithm kwamba
katika kubwa O ya 1?

192
00:08:15,930 --> 00:08:18,350
>> Watazamaji: Kupata urefu
ya kutofautiana.

193
00:08:18,350 --> 00:08:21,090
>> DAVID Malan: Kupata
urefu wa kutofautiana?

194
00:08:21,090 --> 00:08:23,870
>> Watazamaji: Hapana, urefu
kama ni tayari Iliyopangwa.

195
00:08:23,870 --> 00:08:24,160
>> DAVID Malan: Good.

196
00:08:24,160 --> 00:08:27,850
OK, hivyo kutafuta urefu wa kitu
kama urefu wa kitu ambacho, kama

197
00:08:27,850 --> 00:08:30,020
safu, ni kuhifadhiwa katika variable fulani.

198
00:08:30,020 --> 00:08:33,380
Kwa sababu unaweza kusoma tu kutofautiana,
au magazeti kutofautiana, au

199
00:08:33,380 --> 00:08:34,960
ujumla tu kupata kwamba kutofautiana.

200
00:08:34,960 --> 00:08:37,299
Na voilà, kwamba inachukua muda mara kwa mara.

201
00:08:37,299 --> 00:08:38,909
>> Kwa upande mwingine, kufikiri nyuma scratch.

202
00:08:38,909 --> 00:08:42,460
Fikiria nyuma kwenye wiki ya kwanza ya C,
wito tu printf na uchapishaji

203
00:08:42,460 --> 00:08:46,240
kitu juu ya screen ni arguably
wakati mara kwa mara, kwa sababu tu inachukua

204
00:08:46,240 --> 00:08:50,880
baadhi ya idadi ya mzunguko CPU kuonyesha
kwamba maandishi kwenye screen.

205
00:08:50,880 --> 00:08:52,720
Au kusubiri - gani?

206
00:08:52,720 --> 00:08:56,430
Jinsi mwingine ili sisi mfano
utendaji wa printf?

207
00:08:56,430 --> 00:09:00,420
Je, mtu kama hawakubaliani, kwamba
labda si kweli mara kwa mara wakati?

208
00:09:00,420 --> 00:09:03,600
Kwa namna gani wanaweza printf mbio
wakati, kwa kweli uchapishaji kamba juu ya

209
00:09:03,600 --> 00:09:05,580
screen, kuwa kitu
chochote zaidi ya mara kwa mara.

210
00:09:05,580 --> 00:09:07,860
>> Watazamaji: [inaudible].

211
00:09:07,860 --> 00:09:08,230
>> DAVID Malan: Yeah.

212
00:09:08,230 --> 00:09:09,300
Hivyo inategemea mtazamo wetu.

213
00:09:09,300 --> 00:09:13,390
Kama sisi kweli nadhani ya pembejeo kwa
printf kama kuwa kamba, na

214
00:09:13,390 --> 00:09:16,380
hiyo sisi kupima ukubwa wa kwamba
pembejeo na urefu wake - hivyo hebu piga

215
00:09:16,380 --> 00:09:17,780
kwamba urefu n pia -

216
00:09:17,780 --> 00:09:21,990
arguably, printf yenyewe ni kubwa O ya n
kwa sababu ni kwenda kuchukua wewe n hatua

217
00:09:21,990 --> 00:09:24,750
magazeti nje ya kila aina ya wale n
wahusika, uwezekano mkubwa.

218
00:09:24,750 --> 00:09:27,730
Angalau kwa kiasi kwamba sisi kudhani
kwamba labda ni kutumia kwa kitanzi

219
00:09:27,730 --> 00:09:28,560
chini ya Hood.

220
00:09:28,560 --> 00:09:30,860
>> Lakini tunataka kuwa na kuangalia kwamba
Kanuni kuelewa ni bora zaidi.

221
00:09:30,860 --> 00:09:33,650
Na kwa kweli, mara moja nyie kuanza
kuchambua yako algorithms mwenyewe, itabidi

222
00:09:33,650 --> 00:09:34,900
literally kufanya tu.

223
00:09:34,900 --> 00:09:37,765
Aina ya mboni ya kanuni yako na kufikiri
kuhusu - haki ya wote, nina hii kitanzi

224
00:09:37,765 --> 00:09:41,870
hapa au nina mizunguko Furushi hapa,
kwamba kinaendelea kufanya mambo n n nyakati,

225
00:09:41,870 --> 00:09:46,050
na unaweza aina ya sababu njia yako
kupitia kanuni, hata kama ni

226
00:09:46,050 --> 00:09:47,980
pseudocode na si halisi ya kanuni.

227
00:09:47,980 --> 00:09:49,730
>> Basi nini kuhusu omega ya n squared?

228
00:09:49,730 --> 00:09:53,582
Nini ilikuwa algorithm kwamba katika bora
kesi, bado alichukua hatua squared n?

229
00:09:53,582 --> 00:09:54,014
Yeah?

230
00:09:54,014 --> 00:09:54,880
>> Watazamaji: [inaudible].

231
00:09:54,880 --> 00:09:55,900
>> DAVID Malan: Hivyo uteuzi aina.

232
00:09:55,900 --> 00:09:59,150
Kwa sababu katika tatizo kwamba kweli kupunguzwa
na ukweli kwamba tena, sijui

233
00:09:59,150 --> 00:10:02,600
Nimepata ndogo mpaka sasa
Nimekuwa checked mambo yote darn.

234
00:10:02,600 --> 00:10:08,050
Hivyo omega ya, kusema, n, sisi
alikuja tu na moja.

235
00:10:08,050 --> 00:10:09,300
Kuingizwa aina.

236
00:10:09,300 --> 00:10:12,370
Kama orodha kinachotokea ya kutatuliwa
tayari, katika kesi bora sisi tu

237
00:10:12,370 --> 00:10:15,090
kufanya moja kupita njia hiyo,
saa ambayo kumweka sisi ni uhakika.

238
00:10:15,090 --> 00:10:17,890
Na kisha hiyo inaweza kuwa alisema
kuwa linear, kwa uhakika.

239
00:10:17,890 --> 00:10:20,570
>> Nini kuhusu omega ya 1?

240
00:10:20,570 --> 00:10:23,790
Nini, katika kesi bora, inaweza kuchukua
simu mara kwa mara ya hatua?

241
00:10:23,790 --> 00:10:27,220
Hivyo linear tafuta, kama wewe tu kupata bahati
na kipengele wewe ni kuangalia

242
00:10:27,220 --> 00:10:31,000
ni haki katika mwanzo wa orodha,
kama hiyo ambapo wewe ni mapya yako

243
00:10:31,000 --> 00:10:33,070
linear traversal wa orodha hiyo.

244
00:10:33,070 --> 00:10:35,180
>> Na hii ni ya kweli ya
idadi ya mambo.

245
00:10:35,180 --> 00:10:37,660
Kwa mfano, hata binary
kutafuta ni omega ya 1.

246
00:10:37,660 --> 00:10:40,310
Kwa sababu nini kama wewe kupata kweli darn
bahati na Smack-dab katika katikati ya

247
00:10:40,310 --> 00:10:42,950
safu yako ni idadi
wewe ni kuangalia kwa?

248
00:10:42,950 --> 00:10:45,730
Hivyo unaweza kupata bahati huko, kama vile.

249
00:10:45,730 --> 00:10:49,190
>> Hii moja, mwishowe, omega ya n logi n.

250
00:10:49,190 --> 00:10:52,573
Hivyo n logi n, sisi si kweli
majadiliano juu bado, lakini -

251
00:10:52,573 --> 00:10:53,300
>> Watazamaji: Merge aina?

252
00:10:53,300 --> 00:10:53,960
>> DAVID Malan: Merge aina.

253
00:10:53,960 --> 00:10:56,920
Hiyo ilikuwa cliffhanger ya wakati wa mwisho,
ambapo sisi mapendekezo, na sisi ilionyesha

254
00:10:56,920 --> 00:10:58,600
kuibua, kwamba kuna algorithms.

255
00:10:58,600 --> 00:11:02,470
Na kuunganisha aina moja tu ya vile
algorithm kwamba kimsingi ni kasi

256
00:11:02,470 --> 00:11:03,450
kuliko baadhi ya guys haya mengine.

257
00:11:03,450 --> 00:11:07,800
Kwa kweli, kuunganisha short siyo tu katika
bora kesi n n logi, katika mbaya

258
00:11:07,800 --> 00:11:09,460
kesi n n gogo.

259
00:11:09,460 --> 00:11:14,540
Na wakati una hii bahati mbaya ya
omega na kubwa O kuwa kitu kimoja?

260
00:11:14,540 --> 00:11:17,310
Tunaweza kweli kueleza kwamba kama nini
kuitwa theta, ingawa ni

261
00:11:17,310 --> 00:11:18,220
kidogo chini ya kawaida.

262
00:11:18,220 --> 00:11:21,730
Lakini hiyo ina maana tu mipaka miwili,
katika kesi hii, ni sawa.

263
00:11:21,730 --> 00:11:25,770
>> Hivyo kuunganisha aina, je, hii
kweli jipu chini kwa ajili yetu?

264
00:11:25,770 --> 00:11:27,000
Naam, kukumbuka motisha.

265
00:11:27,000 --> 00:11:30,340
Hebu vuta hadi mwingine uhuishaji kwamba
sisi hawakuwa kuangalia wakati wa mwisho.

266
00:11:30,340 --> 00:11:33,390
Hii moja, wazo moja, lakini
ni kidogo kubwa.

267
00:11:33,390 --> 00:11:36,160
Na mimi nina kwenda mbele na kumweka nje
kwanza - tuna aina kuingizwa kwenye

268
00:11:36,160 --> 00:11:39,410
upande wa juu kushoto, basi uteuzi aina,
Bubble aina, ya wanandoa wa aina nyingine -

269
00:11:39,410 --> 00:11:42,670
shell na ya haraka - kwamba sisi si aliongea
kuhusu, na chungu na kuunganisha aina.

270
00:11:42,670 --> 00:11:47,090
>> Hivyo angalau kujaribu kuzingatia macho yako juu
tatu za juu upande wa kushoto na kisha

271
00:11:47,090 --> 00:11:49,120
kuunganisha aina wakati mimi bonyeza
hii mshale kijani.

272
00:11:49,120 --> 00:11:51,900
Lakini mimi itabidi basi wao wote kukimbia, tu
kukupa hisia ya utofauti wa

273
00:11:51,900 --> 00:11:53,980
algorithms ambazo zipo katika dunia.

274
00:11:53,980 --> 00:11:56,180
Mimi nina kwenda basi hii kukimbia
kwa sekunde chache tu.

275
00:11:56,180 --> 00:11:59,640
Na kama wewe lengo macho yako - pick
algorithm, kuzingatia ni kwa ajili tu ya

276
00:11:59,640 --> 00:12:02,970
sekunde - utasikia kuanza kuona
mfano kwamba ni utekelezaji.

277
00:12:02,970 --> 00:12:04,530
>> Aina kuunganisha, ilani, ni kosa.

278
00:12:04,530 --> 00:12:06,430
Lundo aina, haraka aina, shell -

279
00:12:06,430 --> 00:12:09,480
hivyo inaonekana sisi ilianzisha tatu
mbaya zaidi algorithms wiki iliyopita.

280
00:12:09,480 --> 00:12:12,960
Lakini hiyo ni nzuri kwamba sisi ni hapa leo
kuangalia aina kuunganisha, ambayo ni moja ya

281
00:12:12,960 --> 00:12:16,500
ndio rahisi ni kuangalia, hata
ingawa pengine bend akili yako

282
00:12:16,500 --> 00:12:17,490
kidogo tu.

283
00:12:17,490 --> 00:12:21,130
Hapa tunaweza kuona ni kiasi gani
uteuzi aina sucks.

284
00:12:21,130 --> 00:12:24,600
>> Lakini kwa upande flip, ni
kweli ni rahisi kutekeleza.

285
00:12:24,600 --> 00:12:28,160
Na labda kwa ajili ya P Set 3, hiyo ni moja ya
algorithms alichagua kutekeleza

286
00:12:28,160 --> 00:12:28,960
kwa toleo la kawaida.

287
00:12:28,960 --> 00:12:30,970
Kikamilifu faini, kikamilifu sahihi.

288
00:12:30,970 --> 00:12:35,210
>> Lakini tena, kama n anapata kubwa, kama wewe
kuchagua kutekeleza algorithm kasi

289
00:12:35,210 --> 00:12:39,020
kama kuunganisha aina, ni tabia mbaya katika kubwa na
kubwa za pembejeo, code yako ni ya haki

290
00:12:39,020 --> 00:12:39,800
kwenda kukimbia kwa kasi zaidi.

291
00:12:39,800 --> 00:12:41,090
Tovuti yako ya kwenda kufanya kazi bora.

292
00:12:41,090 --> 00:12:42,650
Watumiaji yako ni kwenda kuwa furaha.

293
00:12:42,650 --> 00:12:45,280
Na hivyo kuna athari hizi
ya kweli kutoa

294
00:12:45,280 --> 00:12:47,350
sisi baadhi undani mawazo.

295
00:12:47,350 --> 00:12:49,990
>> Basi hebu tuangalie nini kuunganisha
aina ni kweli yote juu.

296
00:12:49,990 --> 00:12:52,992
jambo zuri ni kwamba kuunganisha
aina ni tu hii.

297
00:12:52,992 --> 00:12:56,300
Hii ni, tena, kile ambacho tumekuwa aitwaye
pseudocode, pseudocode kiumbe

298
00:12:56,300 --> 00:12:57,720
Kiingereza-kama syntax.

299
00:12:57,720 --> 00:12:59,890
Na unyenyekevu ni
aina ya kuvutia.

300
00:12:59,890 --> 00:13:02,840
>> Hivyo juu ya pembejeo ya mambo n - ili
njia tu, hapa ni safu.

301
00:13:02,840 --> 00:13:04,000
Ni got mambo n ndani yake.

302
00:13:04,000 --> 00:13:05,370
Kwamba wote sisi ni kusema huko.

303
00:13:05,370 --> 00:13:07,560
>> Kama n ni chini ya 2, kurudi.

304
00:13:07,560 --> 00:13:08,640
Hivyo kwamba ni tu kesi yasiyo na maana.

305
00:13:08,640 --> 00:13:12,580
Kama n ni chini ya 2, basi ni wazi ni
1 au 0, katika kesi ambayo kitu

306
00:13:12,580 --> 00:13:14,780
tayari yamepangwa au haipo,
hivyo tu kurudi.

307
00:13:14,780 --> 00:13:15,900
Kuna kitu cha kufanya.

308
00:13:15,900 --> 00:13:18,360
Hivyo kwamba ni kesi rahisi kuvunja mbali.

309
00:13:18,360 --> 00:13:20,110
>> Mwingine, tuna hatua tatu.

310
00:13:20,110 --> 00:13:23,650
Kutatua nusu ya kushoto ya mambo, aina
nusu haki ya vipengele,

311
00:13:23,650 --> 00:13:26,650
na kisha kuunganisha nusu Iliyopangwa.

312
00:13:26,650 --> 00:13:29,400
Nini kuvutia hapa ni kwamba
Mimi nina aina ya punting, haki?

313
00:13:29,400 --> 00:13:32,300
Kuna aina ya ufafanuzi mviringo
kwa algorithm hii.

314
00:13:32,300 --> 00:13:35,986
Katika maana gani ni hii ya algorithm
ufafanuzi mviringo?

315
00:13:35,986 --> 00:13:37,850
>> Watazamaji: [inaudible].

316
00:13:37,850 --> 00:13:41,670
>> DAVID Malan: Yeah, kuchagua yangu algorithm,
mbili ya hatua yake ni "aina

317
00:13:41,670 --> 00:13:44,640
kitu ". Na hivyo kwamba anaomba
swali, vizuri, je, Mimi naenda kutumia

318
00:13:44,640 --> 00:13:46,460
kutatua nusu ya kushoto
na nusu ya haki?

319
00:13:46,460 --> 00:13:49,600
Na uzuri hapa ni kwamba hata kama
tena, hii ni akili-bending

320
00:13:49,600 --> 00:13:54,030
sehemu uwezekano, unaweza kutumia moja
algorithm kutatua nusu ya kushoto.

321
00:13:54,030 --> 00:13:54,700
>> Lakini kusubiri dakika.

322
00:13:54,700 --> 00:13:57,070
Wakati wewe ni aliiambia kutatua
nusu ya kushoto, kile ni mbili

323
00:13:57,070 --> 00:13:58,240
hatua kwenda kuwa ijayo?

324
00:13:58,240 --> 00:14:00,550
Tutaweza kutatua nusu ya kushoto ya
kushoto na kulia nusu

325
00:14:00,550 --> 00:14:01,420
nusu ya nusu ya kushoto.

326
00:14:01,420 --> 00:14:04,430
Damn, jinsi gani mimi aina hizo mbili
nusu, au robo, sasa?

327
00:14:04,430 --> 00:14:05,260
>> Lakini hiyo ni sawa.

328
00:14:05,260 --> 00:14:07,830
Tuna algorithm kuchagua hapa.

329
00:14:07,830 --> 00:14:10,660
Na hata ingawa unaweza wasiwasi katika
kwanza hii ni aina ya usio

330
00:14:10,660 --> 00:14:12,780
kitanzi, ni mzunguko kwamba kamwe
kwenda mwisho - ni kwenda

331
00:14:12,780 --> 00:14:15,770
kukomesha mara moja nini hufanyika?

332
00:14:15,770 --> 00:14:16,970
Mara moja n ni chini ya 2.

333
00:14:16,970 --> 00:14:19,180
Ambayo hatimaye kinaenda kutokea,
kwa sababu kama wewe kuweka hesabu za nusu na

334
00:14:19,180 --> 00:14:23,020
kupunguza nusu katika kupunguza nusu nusu hizi, hakika
hatimaye wewe ni kwenda mwisho

335
00:14:23,020 --> 00:14:25,350
juu na tu 1 au 0 vipengele.

336
00:14:25,350 --> 00:14:28,500
Saa ambayo kumweka, hii algorithm
anasema wewe ni kosa.

337
00:14:28,500 --> 00:14:31,020
>> Hivyo uchawi kweli katika hii
algorithm inaonekana kuwa katika

338
00:14:31,020 --> 00:14:33,470
kwamba hatua ya mwisho, kuunganisha.

339
00:14:33,470 --> 00:14:37,190
Kwamba wazo rahisi tu kuunganisha mbili
mambo, kwamba ni nini hatimaye kwenda

340
00:14:37,190 --> 00:14:40,920
kuruhusu yetu ya kutatua safu ya,
hebu sema, mambo nane.

341
00:14:40,920 --> 00:14:44,410
Hivyo nina nane mipira mkazo zaidi juu
hapa, nane vipande vya karatasi, na moja

342
00:14:44,410 --> 00:14:45,500
Google kioo -

343
00:14:45,500 --> 00:14:46,140
ambayo mimi kupata kushika.

344
00:14:46,140 --> 00:14:46,960
>> [Kicheko]

345
00:14:46,960 --> 00:14:48,970
>> DAVID Malan: Kama sisi inaweza kuchukua nane
kujitolea, na hebu angalia kama tunaweza

346
00:14:48,970 --> 00:14:51,430
kucheza nje, hivyo.

347
00:14:51,430 --> 00:14:52,500
Wow, OK.

348
00:14:52,500 --> 00:14:53,565
Sayansi ya kompyuta ni kupata furaha.

349
00:14:53,565 --> 00:14:54,320
Wote haki.

350
00:14:54,320 --> 00:14:57,770
Hivyo vipi kuhusu wewe tatu,
kubwa mkono hadi pale.

351
00:14:57,770 --> 00:14:58,580
Nne katika nyuma.

352
00:14:58,580 --> 00:15:02,220
Na vipi kuhusu tutaweza kufanya wewe
tatu katika safu hii?

353
00:15:02,220 --> 00:15:03,390
Na nne mbele.

354
00:15:03,390 --> 00:15:04,920
Hivyo nane, kuja juu juu.

355
00:15:04,920 --> 00:15:12,060
>> [Kicheko]

356
00:15:12,060 --> 00:15:13,450
>> DAVID Malan: Mimi kwa kweli
uhakika ni nini.

357
00:15:13,450 --> 00:15:14,810
Je, ni mipira ya dhiki?

358
00:15:14,810 --> 00:15:16,510
taa dawati?

359
00:15:16,510 --> 00:15:18,650
nyenzo?

360
00:15:18,650 --> 00:15:19,680
internet?

361
00:15:19,680 --> 00:15:20,160
>> OK.

362
00:15:20,160 --> 00:15:21,310
Hivyo kuja juu juu.

363
00:15:21,310 --> 00:15:22,310
Ambao wangependa -

364
00:15:22,310 --> 00:15:23,570
kuendelea kuja juu.

365
00:15:23,570 --> 00:15:24,240
Hebu angalia.

366
00:15:24,240 --> 00:15:26,460
Na hii unaweka katika eneo -

367
00:15:26,460 --> 00:15:27,940
uko katika eneo moja.

368
00:15:27,940 --> 00:15:28,670
Uh-oh, kusubiri dakika.

369
00:15:28,670 --> 00:15:30,760
1, 2, 3, 4, 5, 6, 7 - oh, nzuri.

370
00:15:30,760 --> 00:15:31,310
Haki wote, sisi ni nzuri.

371
00:15:31,310 --> 00:15:35,130
Haki ya wote, hivyo kila mtu kuwa na kiti,
lakini si kwa kioo Google.

372
00:15:35,130 --> 00:15:36,475
Hebu kwa foleni haya juu.

373
00:15:36,475 --> 00:15:37,115
Nini jina lako?

374
00:15:37,115 --> 00:15:37,440
>> MICHELLE: Michelle.

375
00:15:37,440 --> 00:15:38,090
>> DAVID Malan: Michelle?

376
00:15:38,090 --> 00:15:42,000
Wote haki, kupata na kuangalia kama
geek, kama kwamba ni sawa.

377
00:15:42,000 --> 00:15:44,625
Naam, mimi pia, nadhani,
kwa muda tu.

378
00:15:44,625 --> 00:15:45,875
Haki ya wote, kusubiri.

379
00:15:45,875 --> 00:15:48,510

380
00:15:48,510 --> 00:15:50,950
Tumekuwa kujaribu kuja na
kutumia kesi kwa ajili ya Google kioo, na sisi

381
00:15:50,950 --> 00:15:53,750
walidhani itakuwa furaha tu kufanya
hii wakati watu ni onstage.

382
00:15:53,750 --> 00:15:57,120
Tutarekodi dunia
kwa mtazamo wao.

383
00:15:57,120 --> 00:15:58,410
Wote haki.

384
00:15:58,410 --> 00:15:59,830
Si pengine kile Google yaliyokusudiwa.

385
00:15:59,830 --> 00:16:02,260
Haki ya yote, kama huna akili amevaa
hili kwa dakika ijayo Awkward,

386
00:16:02,260 --> 00:16:03,150
kwamba itakuwa ya ajabu.

387
00:16:03,150 --> 00:16:08,620
>> Haki wote, hivyo sisi hapa safu ya
mambo, na kwamba safu, kama kwa

388
00:16:08,620 --> 00:16:11,480
vipande vya karatasi katika folks hizi '
mikono, kwa sasa ni zisizochambuliwa.

389
00:16:11,480 --> 00:16:12,050
>> MICHELLE: Oh, hiyo ni kioja.

390
00:16:12,050 --> 00:16:12,810
>> DAVID Malan: Ni pretty much random.

391
00:16:12,810 --> 00:16:15,760
Na katika muda tu, sisi ni kwenda kujaribu
kutekeleza kuunganisha aina pamoja

392
00:16:15,760 --> 00:16:17,950
na kuona ambapo kwamba ufahamu muhimu ni.

393
00:16:17,950 --> 00:16:21,970
Na hila hapa na aina kuunganisha ni
kitu ambacho sisi si kudhani bado.

394
00:16:21,970 --> 00:16:24,030
Sisi kwa kweli haja ya baadhi ya
ziada nafasi.

395
00:16:24,030 --> 00:16:26,650
Hivyo nini kinaendelea kuwa hasa
kuvutia kuhusu hili ni kwamba hawa

396
00:16:26,650 --> 00:16:29,270
guys ni kwenda kuzunguka kidogo
kidogo, kwa sababu mimi naenda kwa kudhani kwamba

397
00:16:29,270 --> 00:16:31,880
kuna safu ya ziada ya nafasi,
kusema, haki ya nyuma yao.

398
00:16:31,880 --> 00:16:34,570
>> Hivyo kama wao uko nyuma ya mwenyekiti wao,
hiyo ni safu ya sekondari.

399
00:16:34,570 --> 00:16:36,960
Kama uko ameketi hapa, hiyo ni
safu ya msingi.

400
00:16:36,960 --> 00:16:40,170
Lakini hii ni rasilimali ya kwamba tuna
si leveraged hivi sasa na Bubble

401
00:16:40,170 --> 00:16:42,040
aina, na aina ya uteuzi,
na aina ya kuingizwa.

402
00:16:42,040 --> 00:16:44,600
Kukumbuka wiki iliyopita, kila mtu tu
aina ya shuffled katika mahali.

403
00:16:44,600 --> 00:16:46,840
Hawakuwa na matumizi yoyote kumbukumbu ya ziada.

404
00:16:46,840 --> 00:16:49,310
Tukiwa na chumba kwa ajili ya watu na
kuhamia watu duniani.

405
00:16:49,310 --> 00:16:50,580
>> Hivyo hii ni ufahamu muhimu, pia.

406
00:16:50,580 --> 00:16:53,410
Kuna hii biashara-off, kwa ujumla katika
sayansi ya kompyuta, ya rasilimali.

407
00:16:53,410 --> 00:16:55,800
Kama unataka kuongeza kasi ya kitu
kama muda, wewe ni kwenda

408
00:16:55,800 --> 00:16:56,900
na kulipa bei.

409
00:16:56,900 --> 00:17:00,750
Na moja ya bei hizo ni mara nyingi sana
nafasi, kiasi cha kumbukumbu au ngumu

410
00:17:00,750 --> 00:17:01,700
disk nafasi ya kuwa unatumia.

411
00:17:01,700 --> 00:17:03,640
Au, kusema ukweli, kiasi
ya muda programu.

412
00:17:03,640 --> 00:17:06,700
Kiasi gani wakati inachukua wewe, mwanadamu,
kwa kweli kutekeleza baadhi ya zaidi

413
00:17:06,700 --> 00:17:07,829
ngumu algorithm.

414
00:17:07,829 --> 00:17:09,760
Lakini kwa leo, biashara-off
ni muda na nafasi.

415
00:17:09,760 --> 00:17:11,930
>> Hivyo kama wewe guys inaweza kushikilia tu juu yako
namba ili tuweze kuona kwamba wewe ni

416
00:17:11,930 --> 00:17:15,839
kweli vinavyolingana 4, 2, 6, 1, 3, 7, 8.

417
00:17:15,839 --> 00:17:16,599
Bora.

418
00:17:16,599 --> 00:17:19,520
Hivyo nina kwenda kujaribu orchestrate
mambo, kama wewe guys unaweza tu

419
00:17:19,520 --> 00:17:21,800
kufuata kuongoza yangu hapa.

420
00:17:21,800 --> 00:17:26,650
>> Kwa hiyo mimi ni kwenda kutekeleza, kwanza,
hatua ya kwanza ya pseudocode, ambayo ni

421
00:17:26,650 --> 00:17:29,440
juu ya pembejeo ya mambo n, ikiwa n ni
chini ya 2, halafu arudi.

422
00:17:29,440 --> 00:17:31,370
Ni wazi, kwamba hana
kuomba, hivyo sisi kuondoka.

423
00:17:31,370 --> 00:17:33,340
Hivyo kutatua nusu ya kushoto ya vipengele.

424
00:17:33,340 --> 00:17:36,220
Hivyo kwamba maana mimi nina kwenda kuzingatia yangu
tahadhari kwa muda tu juu ya haya

425
00:17:36,220 --> 00:17:37,310
wanne guys hapa.

426
00:17:37,310 --> 00:17:39,774
Wote haki, je, mimi ijayo kufanya?

427
00:17:39,774 --> 00:17:40,570
>> Watazamaji: aina nusu ya kushoto.

428
00:17:40,570 --> 00:17:42,780
>> DAVID Malan: Basi sasa nina kutatua
nusu ya kushoto ya guys haya.

429
00:17:42,780 --> 00:17:45,580
Sababu tena, kudhani na wewe mwenyewe
lengo ni kutatua nusu ya kushoto.

430
00:17:45,580 --> 00:17:46,440
Jinsi gani unaweza kufanya hivyo?

431
00:17:46,440 --> 00:17:49,140
Tu kufuata maelekezo, hata
ingawa sisi ni kufanya hivyo tena.

432
00:17:49,140 --> 00:17:50,160
Hivyo kutatua nusu ya kushoto.

433
00:17:50,160 --> 00:17:52,030
Sasa mimi nina kuchagua guys hizi mbili.

434
00:17:52,030 --> 00:17:53,563
Kile unakuja ijayo?

435
00:17:53,563 --> 00:17:54,510
>> Watazamaji: aina nusu ya kushoto.

436
00:17:54,510 --> 00:17:55,460
>> DAVID Malan: aina nusu ya kushoto.

437
00:17:55,460 --> 00:18:00,680
Hivyo sasa hivi, kiti hiki hapa,
ni orodha ya kawaida ya 1.

438
00:18:00,680 --> 00:18:01,365
Na nini jina lako tena?

439
00:18:01,365 --> 00:18:02,390
>> PRINCESS DAISY: Princess Daisy.

440
00:18:02,390 --> 00:18:03,690
>> DAVID Malan: Princess Daisy ni hapa.

441
00:18:03,690 --> 00:18:07,470
Na hivyo yeye tayari ni Iliyopangwa, kwa sababu
orodha ni ya kawaida ya 1.

442
00:18:07,470 --> 00:18:09,490
Je, mimi ijayo kufanya?

443
00:18:09,490 --> 00:18:13,680
OK, kurudi, kwa sababu orodha ya kwamba ni ya
kawaida ya 1, ambayo ni chini ya 2.

444
00:18:13,680 --> 00:18:14,320
Kisha hatua gani ya baadaye?

445
00:18:14,320 --> 00:18:17,490
Na sasa una aina ya
backtrack katika akili yako.

446
00:18:17,490 --> 00:18:19,340
>> Aina nusu haki, ambayo ni -

447
00:18:19,340 --> 00:18:19,570
nini jina lako?

448
00:18:19,570 --> 00:18:20,220
>> LINDA: Linda.

449
00:18:20,220 --> 00:18:20,980
>> DAVID Malan: Linda.

450
00:18:20,980 --> 00:18:23,210
Na hivyo tunafanya nini sasa kwamba
tuna orodha ya kawaida ya 1?

451
00:18:23,210 --> 00:18:24,440
>> Watazamaji: Kurudi.

452
00:18:24,440 --> 00:18:24,760
>> DAVID Malan: Makini.

453
00:18:24,760 --> 00:18:29,540
Sisi kurudi kwanza, na sasa ya tatu
hatua - na kama mimi aina ya depict hivyo kwa

454
00:18:29,540 --> 00:18:33,490
kumuunga viti mbili sasa, sasa mimi
na kuunganisha mambo haya mawili.

455
00:18:33,490 --> 00:18:35,530
Hivyo sasa kwa bahati mbaya, mambo
ni nje ya utaratibu.

456
00:18:35,530 --> 00:18:39,920
Lakini hilo ambapo mchakato kuunganisha
kuanza kupata kulazimisha.

457
00:18:39,920 --> 00:18:42,410
>> Hivyo kama wewe guys inaweza kusimama kwa ajili tu ya
sasa, mimi nina kwenda haja ya wewe, katika

458
00:18:42,410 --> 00:18:44,170
sasa, hatua ya nyuma ya kiti yako.

459
00:18:44,170 --> 00:18:46,480
Na kama Linda, kwa sababu ya 2 ni
ndogo kuliko 4, kwa nini sio

460
00:18:46,480 --> 00:18:48,130
wewe kuja karibu ya kwanza?

461
00:18:48,130 --> 00:18:48,690
Kukaa huko.

462
00:18:48,690 --> 00:18:50,520
Hivyo Linda, wewe kuja duniani kwanza.

463
00:18:50,520 --> 00:18:53,820
>> Sasa katika hali halisi kama ni tu safu
tunaweza tu hoja yake katika muda halisi

464
00:18:53,820 --> 00:18:55,360
kutoka kwa mwenyekiti hii na doa hili.

465
00:18:55,360 --> 00:18:57,770
Hivyo kufikiria kwamba alichukua baadhi ya mara kwa mara
Idadi ya hatua 1.

466
00:18:57,770 --> 00:18:58,480
Na sasa -

467
00:18:58,480 --> 00:19:01,490
lakini tunahitaji kuweka wewe katika
mahali ya kwanza hapa.

468
00:19:01,490 --> 00:19:03,930
>> Na sasa kama unaweza kuja karibu,
kama vile, tunakwenda

469
00:19:03,930 --> 00:19:06,300
kuwa katika eneo mbili.

470
00:19:06,300 --> 00:19:09,120
Na hata kama hii anahisi kama ni
kuchukua muda, nini ni nzuri sasa ni

471
00:19:09,120 --> 00:19:14,710
kwamba nusu ya kushoto ya
nusu ya kushoto ni sasa Iliyopangwa.

472
00:19:14,710 --> 00:19:18,010
Hivyo kile ilikuwa hatua ya pili, kama sisi sasa
rewind zaidi katika hadithi?

473
00:19:18,010 --> 00:19:18,980
>> Watazamaji: Haki nusu.

474
00:19:18,980 --> 00:19:19,900
>> DAVID Malan: aina ya nusu ya haki.

475
00:19:19,900 --> 00:19:21,320
Hivyo wewe guys kuwa kwa kufanya hivyo, kama vile.

476
00:19:21,320 --> 00:19:23,510
Hivyo kama unaweza kusimama
kwa muda tu?

477
00:19:23,510 --> 00:19:25,192
Na nini jina lako?

478
00:19:25,192 --> 00:19:25,540
>> JESS: Jess.

479
00:19:25,540 --> 00:19:25,870
>> DAVID Malan: Jess.

480
00:19:25,870 --> 00:19:29,720
OK, hivyo Jess sasa ni kushoto
nusu ya nusu ya haki.

481
00:19:29,720 --> 00:19:31,400
Na hivyo yeye ni orodha ya kawaida ya 1.

482
00:19:31,400 --> 00:19:32,380
Yeye ni wazi Iliyopangwa.

483
00:19:32,380 --> 00:19:33,070
Na jina yako tena?

484
00:19:33,070 --> 00:19:33,630
>> MICHELLE: Michelle.

485
00:19:33,630 --> 00:19:35,340
>> DAVID Malan: Michelle ni wazi
orodha ya kawaida ya 1.

486
00:19:35,340 --> 00:19:36,050
Yeye ni tayari Iliyopangwa.

487
00:19:36,050 --> 00:19:38,690
Hivyo sasa uchawi ikitokea,
mchakato wa kuunganisha.

488
00:19:38,690 --> 00:19:39,790
Hivyo nani kwenda aje kwanza?

489
00:19:39,790 --> 00:19:41,560
Ni wazi Michelle.

490
00:19:41,560 --> 00:19:43,280
Hivyo kama unaweza kuja kuzunguka nyuma.

491
00:19:43,280 --> 00:19:47,090
tuna nafasi ya kutosha kwa ajili yake sasa
ni haki ya nyuma ya hii kiti hapa.

492
00:19:47,090 --> 00:19:51,580
Na sasa kama unaweza kuja nyuma kama vile,
sisi sasa kuwa, kuwa wazi, mbili,

493
00:19:51,580 --> 00:19:53,810
nusu, kila aina ya ukubwa wa 2 -

494
00:19:53,810 --> 00:19:57,090
na kwa ajili tu ya picha ya Mungu ikiwa wewe
inaweza kufanya kidogo ya nafasi -

495
00:19:57,090 --> 00:19:59,780
mtu wa kushoto nusu hapa, moja
haki ya nusu hapa.

496
00:19:59,780 --> 00:20:01,160
>> Rewind zaidi katika hadithi.

497
00:20:01,160 --> 00:20:02,270
Nini ni hatua inayofuata?

498
00:20:02,270 --> 00:20:03,030
>> Watazamaji: Merge.

499
00:20:03,030 --> 00:20:04,160
>> DAVID Malan: Basi sasa tuna kuunganisha.

500
00:20:04,160 --> 00:20:07,490
Hivyo OK, hivyo kwa sasa, nashiriki, sisi
tu huru hadi viti nne.

501
00:20:07,490 --> 00:20:11,480
Hivyo tumekuwa kutumika mara mbili kama kumbukumbu sana, lakini
tunaweza kutoa flip-flopping kati ya

502
00:20:11,480 --> 00:20:12,330
arrays mbili.

503
00:20:12,330 --> 00:20:14,190
Hivyo ambayo idadi ni aje kwanza?

504
00:20:14,190 --> 00:20:14,850
Hivyo Michelle, ni wazi.

505
00:20:14,850 --> 00:20:16,680
Hivyo kuja karibu na kuchukua
kiti yako hapa.

506
00:20:16,680 --> 00:20:19,120
Na kisha namba 2 ni wazi
ijayo, hivyo kuja hapa.

507
00:20:19,120 --> 00:20:21,520
Namba 4, namba 6.

508
00:20:21,520 --> 00:20:23,390
Na tena, hata kama kuna
kidogo kidogo ya kutembea wanaohusika,

509
00:20:23,390 --> 00:20:26,010
kweli, hizi inaweza kutokea mara moja,
na kuhamia moja -

510
00:20:26,010 --> 00:20:26,880
OK, pia alicheza.

511
00:20:26,880 --> 00:20:28,350
>> [Kicheko]

512
00:20:28,350 --> 00:20:29,680
>> DAVID Malan: Na sasa tuko
katika sura nzuri.

513
00:20:29,680 --> 00:20:34,910
nusu ya kushoto ya nzima
pembejeo sasa imekuwa Iliyopangwa.

514
00:20:34,910 --> 00:20:37,370
Haki wote, hivyo hawa guys alikuwa
faida ya yangu -

515
00:20:37,370 --> 00:20:40,340
jinsi gani kuishia wasichana wote juu ya
kushoto na wavulana wote juu ya haki?

516
00:20:40,340 --> 00:20:42,450
>> OK, hivyo wavulana 'kugeuka sasa.

517
00:20:42,450 --> 00:20:44,680
Hivyo mimi si kutembea wewe kupitia
hatua hizi.

518
00:20:44,680 --> 00:20:46,550
Tutaweza kuona kama tunaweza reapply
pseudocode sawa.

519
00:20:46,550 --> 00:20:50,050
Kama unataka kwenda mbele na kusimama,
na nyie, nikupe mic.

520
00:20:50,050 --> 00:20:52,990
Kuona kama unaweza si kuiga kile
sisi tu alifanya hapa

521
00:20:52,990 --> 00:20:53,880
nyingine ya mwisho wa orodha.

522
00:20:53,880 --> 00:20:59,530
Ambaye anahitaji kusema ya kwanza,
msingi algorithm?

523
00:20:59,530 --> 00:21:03,210
Hivyo waeleze nini unafanya kabla ya
wewe kufanya harakati yoyote mguu.

524
00:21:03,210 --> 00:21:05,930
>> SPIKA 1: zote haki, hivyo tangu
Mimi ni nusu ya kushoto ya

525
00:21:05,930 --> 00:21:07,790
nusu ya kushoto, mimi kurudi.

526
00:21:07,790 --> 00:21:08,730
Haki?

527
00:21:08,730 --> 00:21:09,250
>> DAVID Malan: Good.

528
00:21:09,250 --> 00:21:10,350
>> SPIKA 1: Na kisha -

529
00:21:10,350 --> 00:21:11,800
>> DAVID Malan: Nani anafanya
mic kwenda ijayo?

530
00:21:11,800 --> 00:21:12,920
>> SPIKA 1: Next idadi.

531
00:21:12,920 --> 00:21:14,720
>> SPIKA 2: Kwa hiyo mimi nina haki ya nusu
ya nusu ya kushoto ya

532
00:21:14,720 --> 00:21:17,830
kushoto nusu, na mimi kurudi.

533
00:21:17,830 --> 00:21:18,050
>> DAVID Malan: Good.

534
00:21:18,050 --> 00:21:18,550
Wewe kurudi.

535
00:21:18,550 --> 00:21:21,855
Hivyo sasa nini juu ijayo kwa ajili ya wewe mbili?

536
00:21:21,855 --> 00:21:23,740
>> SPIKA 2: Tunataka kuona nani vidogo vidogo.

537
00:21:23,740 --> 00:21:24,200
>> DAVID Malan: Hasa.

538
00:21:24,200 --> 00:21:24,940
Tunataka kuunganisha.

539
00:21:24,940 --> 00:21:27,590
nafasi tunakwenda kutumia kuunganisha
wewe ndani, hata kama wao ni

540
00:21:27,590 --> 00:21:30,250
wazi yamepangwa tayari, tunakwenda
kufuata algorithm sawa.

541
00:21:30,250 --> 00:21:31,560
Hivyo ambao unaendelea katika nyuma ya kwanza?

542
00:21:31,560 --> 00:21:35,720
Hivyo 3, na kisha 7.

543
00:21:35,720 --> 00:21:38,570
Na sasa mic huenda
haya guys, OK?

544
00:21:38,570 --> 00:21:43,590
>> SPIKA 3: Kwa hiyo mimi nina haki ya nusu
kushoto nusu, na n wangu ni chini ya

545
00:21:43,590 --> 00:21:45,048
1, hivyo mimi nina kwenda tu kupita -

546
00:21:45,048 --> 00:21:46,380
>> DAVID Malan: Good.

547
00:21:46,380 --> 00:21:49,450
>> SPIKA 4: Mimi nina haki ya nusu
haki ya nusu ya nusu ya haki, na mimi nina

548
00:21:49,450 --> 00:21:51,740
pia mtu mmoja, hivyo mimi nina
kwenda na kurudi.

549
00:21:51,740 --> 00:21:52,990
Hivyo sasa sisi kuunganisha.

550
00:21:52,990 --> 00:21:55,140

551
00:21:55,140 --> 00:21:56,150
>> SPIKA 3: Hivyo sisi kurudi nyuma.

552
00:21:56,150 --> 00:21:57,160
>> DAVID Malan: Hivyo wewe kwenda katika nyuma.

553
00:21:57,160 --> 00:21:59,200
Hivyo 5 huenda kwanza, basi 8.

554
00:21:59,200 --> 00:22:01,240
Na sasa watazamaji, ambayo ni
hatua tuna sasa rewind

555
00:22:01,240 --> 00:22:02,200
nyuma na katika akili zetu?

556
00:22:02,200 --> 00:22:02,940
>> Watazamaji: Merge.

557
00:22:02,940 --> 00:22:07,270
>> DAVID Malan: Kuunganisha kushoto nusu na haki
nusu ya nusu ya awali ya kushoto.

558
00:22:07,270 --> 00:22:08,840
Hivyo sasa -

559
00:22:08,840 --> 00:22:10,520
na tu kufanya hili wazi,
kufanya kidogo wa nafasi ya

560
00:22:10,520 --> 00:22:11,690
kati ya wewe guys wawili.

561
00:22:11,690 --> 00:22:13,800
Hivyo sasa hiyo ni orodha mbili,
kushoto na kulia.

562
00:22:13,800 --> 00:22:18,320
Hivyo ni jinsi gani sisi sasa kuunganisha guys katika
mstari wa mbele wa viti tena?

563
00:22:18,320 --> 00:22:19,600
>> 3 huenda kwanza.

564
00:22:19,600 --> 00:22:20,850
Kisha 5, ni wazi.

565
00:22:20,850 --> 00:22:23,110

566
00:22:23,110 --> 00:22:27,330
Kisha 7, na sasa 8.

567
00:22:27,330 --> 00:22:28,710
OK, na sasa sisi ni?

568
00:22:28,710 --> 00:22:29,650
>> Watazamaji: Si kosa.

569
00:22:29,650 --> 00:22:32,440
>> DAVID Malan: Si kosa, kwa sababu
ni wazi, kuna hatua moja iliyobaki.

570
00:22:32,440 --> 00:22:35,720
Lakini tena, sababu mimi nina kutumia hii
jargon kama "rewind katika akili yako,"

571
00:22:35,720 --> 00:22:37,160
ni kwa sababu hiyo kwa kweli
nini kinatokea.

572
00:22:37,160 --> 00:22:39,610
Tunakwenda kupitia hatua zote hizi,
lakini sisi ni aina ya pausing kwa

573
00:22:39,610 --> 00:22:42,480
sasa, mbizi zaidi katika
algorithm, pausing kwa muda,

574
00:22:42,480 --> 00:22:45,840
mbizi zaidi katika algorithm, na
sasa tuna aina ya rewind katika yetu

575
00:22:45,840 --> 00:22:49,430
akili na kuondoa wote wa tabaka hizi
kwamba tumekuwa aina ya kuweka juu ya umiliki.

576
00:22:49,430 --> 00:22:51,790
>> Basi sasa tuna orodha mbili ya ukubwa wa 4.

577
00:22:51,790 --> 00:22:54,790
Kama wewe guys inaweza kusimama mara moja ya mwisho
na kufanya kidogo ya nafasi hapa

578
00:22:54,790 --> 00:22:57,230
kufanya wazi kuwa hii ni kushoto
nusu ya awali,

579
00:22:57,230 --> 00:22:58,620
haki ya nusu ya awali.

580
00:22:58,620 --> 00:23:01,060
Ambaye ni idadi ya kwanza ya kwamba sisi
haja ya kuvuta ndani ya nyuma?

581
00:23:01,060 --> 00:23:01,870
Michelle, bila shaka.

582
00:23:01,870 --> 00:23:03,230
>> Hivyo sisi kuweka Michelle hapa.

583
00:23:03,230 --> 00:23:05,080
Na ambaye ana idadi 2?

584
00:23:05,080 --> 00:23:06,440
Idadi 2 inakuja juu ya nyuma pia.

585
00:23:06,440 --> 00:23:07,800
Namba 3?

586
00:23:07,800 --> 00:23:08,510
Bora.

587
00:23:08,510 --> 00:23:16,570
Namba 4, namba 5, idadi ya 6,
namba 7, na namba 8.

588
00:23:16,570 --> 00:23:18,850
>> OK, hivyo waliona kama mengi
ya hatua, kwa uhakika.

589
00:23:18,850 --> 00:23:22,390
Lakini sasa hebu angalia kama hatuwezi kuthibitisha
aina ya intuitively kwamba hii

590
00:23:22,390 --> 00:23:26,190
algorithm kimsingi, hasa kama
n kweli anapata kubwa, kama tumeona

591
00:23:26,190 --> 00:23:29,170
na mifano kwa michoro, ni
kimsingi kwa kasi zaidi.

592
00:23:29,170 --> 00:23:33,400
Hivyo mimi kudai hii algorithm, katika mbaya
kesi na hata katika kesi bora,

593
00:23:33,400 --> 00:23:36,160
ni kubwa O ya n mara logi n.

594
00:23:36,160 --> 00:23:39,160
Hiyo ni, kuna baadhi ya nyanja ya hii
algorithm kwamba inachukua hatua n, lakini

595
00:23:39,160 --> 00:23:43,110
kuna kipengele mwingine mahali fulani katika
kwamba iteration, kwamba looping, kwamba

596
00:23:43,110 --> 00:23:44,410
inachukua hatua logi n.

597
00:23:44,410 --> 00:23:49,154
Tunaweza kuweka kidole wetu juu ya nini wale
namba mbili ni akimaanisha?

598
00:23:49,154 --> 00:23:51,320
Naam, ambapo -

599
00:23:51,320 --> 00:23:54,160
ambapo 'd mic kwenda?

600
00:23:54,160 --> 00:23:58,660
>> SPIKA 1: Je logi n kuwa
kuvunja sisi juu katika mbili -

601
00:23:58,660 --> 00:23:59,630
kugawa na mbili, kimsingi.

602
00:23:59,630 --> 00:24:00,120
>> DAVID Malan: Hasa.

603
00:24:00,120 --> 00:24:03,000
Wakati wowote tunaona yoyote algorithm hivyo
mbali, kuna kuwa muundo huu wa

604
00:24:03,000 --> 00:24:04,200
kugawa, kugawa, kugawa.

605
00:24:04,200 --> 00:24:05,700
Na ni kawaida kupunguza
kwa kitu ambacho ni

606
00:24:05,700 --> 00:24:07,100
logarithmic, logi msingi 2.

607
00:24:07,100 --> 00:24:10,180
Lakini inaweza kweli kuwa kitu chochote,
lakini kuingia wigo 2.

608
00:24:10,180 --> 00:24:11,330
>> Sasa nini kuhusu n?

609
00:24:11,330 --> 00:24:14,550
Mimi naona kwamba sisi aina ya kugawanywa wewe
guys - kugawanywa wewe, kugawanywa wewe,

610
00:24:14,550 --> 00:24:15,910
kugawanywa wewe, kugawanywa wewe.

611
00:24:15,910 --> 00:24:18,760
Ambapo haina mwisho kuja kutoka?

612
00:24:18,760 --> 00:24:19,810
>> Hivyo ni kuunganisha.

613
00:24:19,810 --> 00:24:20,610
Kwa sababu kufikiri juu yake.

614
00:24:20,610 --> 00:24:25,420
Wakati kuunganisha watu nane kwa pamoja,
ambapo nusu yao ni seti ya nne

615
00:24:25,420 --> 00:24:27,770
na nusu nyingine ni mwingine
seti ya nne, jinsi gani unaweza kwenda

616
00:24:27,770 --> 00:24:28,820
juu ya kufanya kuunganisha?

617
00:24:28,820 --> 00:24:30,830
Naam, wewe guys alifanya hivyo
haki intuitively.

618
00:24:30,830 --> 00:24:34,140
>> Lakini kama mimi badala yake alifanya hivyo zaidi kidogo
methodically, nipate alisema saa

619
00:24:34,140 --> 00:24:38,090
mtu leftmost kwanza na kushoto kwangu
mkono, alisema katika mtu leftmost

620
00:24:38,090 --> 00:24:42,080
ya kwamba nusu kwa mkono wangu wa kulia, na
tu hatimaye kutembea kwa njia ya

621
00:24:42,080 --> 00:24:46,990
orodha, akionyesha kipengele ndogo
kila wakati, kusonga kidole yangu juu na

622
00:24:46,990 --> 00:24:48,970
zaidi kama inahitajika katika orodha.

623
00:24:48,970 --> 00:24:51,890
Lakini nini kuhusu hili muhimu kuunganisha
mchakato ni mimi nina kulinganisha jozi hizi

624
00:24:51,890 --> 00:24:53,460
ya vipengele.

625
00:24:53,460 --> 00:24:57,270
Kutoka nusu kulia na kutoka upande wa kushoto
nusu, mimi nina kamwe mara moja inafuatilia.

626
00:24:57,270 --> 00:25:00,570
>> Hivyo kuunganisha yenyewe ni kuchukua
hakuna zaidi ya n hatua.

627
00:25:00,570 --> 00:25:03,250
Na mara ngapi alifanya nina
kufanya hivyo kuunganisha?

628
00:25:03,250 --> 00:25:07,150
Naam, hakuna zaidi ya n, na sisi tu
akaona ya kuwa na kuunganisha ya mwisho.

629
00:25:07,150 --> 00:25:13,120
Na hivyo kama wewe kufanya kitu kwamba inachukua
kuingia hatua n n mara, au kinyume chake,

630
00:25:13,120 --> 00:25:15,210
ni kwenda kutupa n mara logi n.

631
00:25:15,210 --> 00:25:16,310
>> Na kwa nini hii ni bora?

632
00:25:16,310 --> 00:25:19,600
Naam, kama sisi tayari kujua kuwa logi
n ni bora kuliko n - haki?

633
00:25:19,600 --> 00:25:22,590
Tuliona katika kutafuta binary, kitabu cha simu
mfano, logi n ilikuwa dhahiri

634
00:25:22,590 --> 00:25:23,760
bora kuliko linear.

635
00:25:23,760 --> 00:25:28,420
Hivyo kwamba maana n mara logi n ni
dhahiri zaidi ya mara n mwingine

636
00:25:28,420 --> 00:25:30,390
n, AKA n squared.

637
00:25:30,390 --> 00:25:32,400
Na kwamba ni nini sisi hatimaye kuhisi.

638
00:25:32,400 --> 00:25:34,928
>> Hivyo kubwa ya raundi ya makofi, kama
tunaweza, kwa guys haya.

639
00:25:34,928 --> 00:25:38,920
>> [Makofi]

640
00:25:38,920 --> 00:25:41,550
>> DAVID Malan: Na zimefunguliwa zawadi yako -
unaweza kuweka idadi,

641
00:25:41,550 --> 00:25:44,010
kama ungependa.

642
00:25:44,010 --> 00:25:45,620
Na zimefunguliwa wako zawadi, kama kawaida.

643
00:25:45,620 --> 00:25:47,290
Oh, na sisi kukutumia
Footage, Michelle.

644
00:25:47,290 --> 00:25:48,343
Asante.

645
00:25:48,343 --> 00:25:49,250
Wote haki.

646
00:25:49,250 --> 00:25:50,400
Msaada mwenyewe kwa mpira wa dhiki.

647
00:25:50,400 --> 00:25:54,110
>> Na napenda kuvuta up, katika huo huo,
rafiki yetu Rob Bowden kutoa

648
00:25:54,110 --> 00:25:59,520
mtazamo tofauti kwa kiasi fulani juu ya hili,
tangu unaweza kufikiri kuhusu hizi

649
00:25:59,520 --> 00:26:01,280
yanayotokea katika hatua fulani
njia tofauti.

650
00:26:01,280 --> 00:26:04,750
Kwa kweli, set-up kwa nini Rob kuhusu
kutuonyesha akubali kwamba tumekuwa

651
00:26:04,750 --> 00:26:09,030
tayari amefanya kugawa juu ya
kubwa orodha katika orodha nane ndogo,

652
00:26:09,030 --> 00:26:10,570
kila aina ya kawaida ya 1.

653
00:26:10,570 --> 00:26:13,350
>> Hivyo sisi ni kubadilisha pseudocode
kidogo tu kwa aina ya kupata saa

654
00:26:13,350 --> 00:26:15,320
msingi wazo la jinsi ya kuunganisha matendo.

655
00:26:15,320 --> 00:26:17,600
Lakini wakati mbio ya kile
yeye ni juu ya kufanya bado ni

656
00:26:17,600 --> 00:26:19,110
kwenda kuwa sawa.

657
00:26:19,110 --> 00:26:23,540
Na tena, set-up hapa ni kwamba yeye ni
imeanza na orodha ya nane ya kawaida ya 1.

658
00:26:23,540 --> 00:26:27,730
Hivyo wameweza amekosa sehemu ambapo yeye ni
kweli amefanya n logi, logi n, logi n

659
00:26:27,730 --> 00:26:31,205
kugawa wa pembejeo.

660
00:26:31,205 --> 00:26:32,120
>> [Video avspelning]

661
00:26:32,120 --> 00:26:33,615
>> -Hiyo ni kwa hatua moja.

662
00:26:33,615 --> 00:26:38,270
Kwa hatua mbili, kwa kurudia
kuunganisha jozi ya orodha.

663
00:26:38,270 --> 00:26:39,210
>> DAVID Malan: Hm.

664
00:26:39,210 --> 00:26:41,270
Audio tu ni kuja
nje ya kompyuta yangu.

665
00:26:41,270 --> 00:26:42,520
Hebu jaribu hii tena.

666
00:26:42,520 --> 00:26:45,330

667
00:26:45,330 --> 00:26:48,310
>> -Tu kiholela pick ambayo -
sasa tuna orodha nne.

668
00:26:48,310 --> 00:26:51,590

669
00:26:51,590 --> 00:26:52,120
Kujifunza kabla.

670
00:26:52,120 --> 00:26:53,040
>> DAVID Malan: Kuna sisi kwenda.

671
00:26:53,040 --> 00:27:00,510
>> -Kuunganisha 108 na 15, sisi kumaliza
na orodha 15, 108.

672
00:27:00,510 --> 00:27:07,170
Kuunganisha 50 na 4, sisi
kuishia na 4, 50.

673
00:27:07,170 --> 00:27:12,990
Kuunganisha 8 na 42, sisi
kuishia na 8, 42.

674
00:27:12,990 --> 00:27:19,970
Na kuunganisha 23 na 16, sisi
kuishia na 16, 23.

675
00:27:19,970 --> 00:27:23,270
>> Sasa wetu orodha zote ni ya ukubwa wa 2.

676
00:27:23,270 --> 00:27:26,690
Taarifa kwamba kila moja ya
orodha ya nne ni Iliyopangwa.

677
00:27:26,690 --> 00:27:29,450
Ili tuweze kuanza kuunganisha
jozi ya orodha tena.

678
00:27:29,450 --> 00:27:38,420
Kuunganisha 15 na 108 na 4 na 50, sisi
kwanza kuchukua 4, kisha 15, kisha

679
00:27:38,420 --> 00:27:41,500
50, kisha 108.

680
00:27:41,500 --> 00:27:50,610
Kuunganisha 8, 42 na 16, 23, sisi kwanza kuchukua
8, kisha 16, kisha 23,

681
00:27:50,610 --> 00:27:52,700
kisha 42.

682
00:27:52,700 --> 00:27:57,600
>> Basi sasa tuna mbili tu orodha ya ukubwa
4, ambayo kila mmoja ni Iliyopangwa.

683
00:27:57,600 --> 00:28:01,170
Hivyo sasa sisi kuunganisha orodha hizi mbili.

684
00:28:01,170 --> 00:28:11,835
Kwanza, sisi kuchukua 4, basi sisi kuchukua
8, basi sisi kuchukua 15, kisha 16, basi

685
00:28:11,835 --> 00:28:19,456
23, kisha 42, kisha 50, kisha 108.

686
00:28:19,456 --> 00:28:19,872
>> [MWISHO video avspelning]

687
00:28:19,872 --> 00:28:23,430
>> DAVID Malan: Tena, angalia, yeye kamwe
kuguswa kikombe kupewa zaidi ya mara moja

688
00:28:23,430 --> 00:28:24,860
baada ya kuendeleza zaidi ya hilo.

689
00:28:24,860 --> 00:28:26,200
Hivyo yeye kamwe kurudia.

690
00:28:26,200 --> 00:28:29,850
Hivyo yeye daima kuhamia upande,
na hiyo ambapo tulipata n wetu.

691
00:28:29,850 --> 00:28:33,290
>> Kwa nini basi mimi kuvuta up moja uhuishaji
kwamba tuliona mapema, lakini wakati huu

692
00:28:33,290 --> 00:28:35,110
kulenga tu juu ya aina kuunganisha.

693
00:28:35,110 --> 00:28:38,030
Hebu kwenda mbele na kuvuta
katika hii hapa.

694
00:28:38,030 --> 00:28:42,530
Kwanza napenda kuchagua pembejeo random,
ukuu wa hii, na unaweza aina ya kuona

695
00:28:42,530 --> 00:28:46,600
nini sisi alichukua kwa nafasi, awali,
kuunganisha aina ni kweli kufanya.

696
00:28:46,600 --> 00:28:50,330
>> Hivyo taarifa kwamba wewe kupata nusu hizi au
hizi robo au haya eighths ya

697
00:28:50,330 --> 00:28:53,140
tatizo kwamba ghafla
kuanza kuchukua sura nzuri.

698
00:28:53,140 --> 00:28:57,070
Na kisha hatimaye, unaweza kuona katika
mwisho sana kwamba bam,

699
00:28:57,070 --> 00:28:58,860
kila kitu ni zimeunganishwa pamoja.

700
00:28:58,860 --> 00:29:01,690
>> Basi hizi ni baadhi tu ya tatu tofauti
inachukua wazo moja.

701
00:29:01,690 --> 00:29:05,980
Lakini ufahamu muhimu, kama kugawanya
na kushinda katika darasa ya kwanza kabisa,

702
00:29:05,980 --> 00:29:10,640
ilikuwa kwamba tuliamua namna fulani kugawanya
tatizo katika jambo kubwa, ndani ya

703
00:29:10,640 --> 00:29:14,760
kitu aina ya kufanana katika roho,
lakini na ndogo ndogo na ndogo

704
00:29:14,760 --> 00:29:15,660
na vidogo vidogo.

705
00:29:15,660 --> 00:29:18,420
>> Sasa mwingine njia ya kujifurahisha na aina ya kufikiri
kuhusu hizi, ingawa si

706
00:29:18,420 --> 00:29:20,520
kwenda kukupa angavu huo
uelewa, ni

707
00:29:20,520 --> 00:29:21,640
uhuishaji zifuatazo.

708
00:29:21,640 --> 00:29:25,400
Hivyo hii ni mtu video kuweka pamoja
kwamba kuhusishwa tofauti

709
00:29:25,400 --> 00:29:29,970
sauti na shughuli mbalimbali kwa ajili ya
kuingizwa aina, kwa ajili ya aina kuunganisha, na

710
00:29:29,970 --> 00:29:31,150
kwa wanandoa wa wengine.

711
00:29:31,150 --> 00:29:32,330
Hivyo katika wakati huu, mimi naenda kumtwanga Play.

712
00:29:32,330 --> 00:29:33,600
Ni kuhusu muda wa dakika.

713
00:29:33,600 --> 00:29:37,410
Na hata ingawa bado unaweza kuona
chati kinatokea, wakati huu unaweza

714
00:29:37,410 --> 00:29:41,420
pia kusikia jinsi hawa algorithms ni
kufanya tofauti na kwa

715
00:29:41,420 --> 00:29:43,950
tofauti chati.

716
00:29:43,950 --> 00:29:45,830
>> Hii ni kuingizwa aina.

717
00:29:45,830 --> 00:29:50,400
>> [Tani KUCHEZA]

718
00:29:50,400 --> 00:29:52,400
>> DAVID Malan: Ni tena ni kujaribu
kuingiza kila kipengele

719
00:29:52,400 --> 00:29:52,900
ndani ambapo ni mali.

720
00:29:52,900 --> 00:29:54,628
Hii ni Bubble aina.

721
00:29:54,628 --> 00:30:10,097
>> [Tani KUCHEZA]

722
00:30:10,097 --> 00:30:13,630
>> DAVID Malan: Na unaweza aina ya kujisikia
jinsi kiasi kidogo kazi ni kufanya

723
00:30:13,630 --> 00:30:15,834
juu ya kila hatua.

724
00:30:15,834 --> 00:30:20,470
Hii ni nini tediousness inaonekana kama.

725
00:30:20,470 --> 00:30:21,472
>> [Tani KUCHEZA]

726
00:30:21,472 --> 00:30:25,222
>> DAVID Malan: Hii ni uteuzi aina,
ambapo sisi kuchagua kipengele tunataka na

727
00:30:25,222 --> 00:30:28,845
kwenda kupitia tena na tena na tena
na kuweka mwanzoni.

728
00:30:28,845 --> 00:30:37,674
>> [Tani KUCHEZA]

729
00:30:37,674 --> 00:30:43,970
>> DAVID Malan: Hii ni kuunganisha aina, ambayo
kweli unaweza kuanza kuhisi.

730
00:30:43,970 --> 00:30:51,810
>> [Tani KUCHEZA]

731
00:30:51,810 --> 00:30:54,770
>> [Kicheko]

732
00:30:54,770 --> 00:30:58,395
>> DAVID Malan: Kitu inaitwa mbilikimo
aina, ambayo sisi si inaonekana saa.

733
00:30:58,395 --> 00:31:13,630
>> [Tani KUCHEZA]

734
00:31:13,630 --> 00:31:17,910
>> DAVID Malan: Hivyo basi mimi kuona sasa,
aliwasihi kama wewe ni matumaini na

735
00:31:17,910 --> 00:31:21,110
muziki, kama naweza kuingizwa kidogo
kidogo ya math katika hapa.

736
00:31:21,110 --> 00:31:24,850
Hivyo kuna njia nne kwamba tunaweza
kufikiri juu ya nini maana ya haya

737
00:31:24,850 --> 00:31:29,210
kazi kuwa kasi zaidi kuliko wale wa
kwamba tumekuwa kuona mbele.

738
00:31:29,210 --> 00:31:32,470
Na kama wewe ni kuja saa shaka kutoka
background hisabati, wewe

739
00:31:32,470 --> 00:31:36,030
kweli kujua labda tayari kwamba
unaweza kofi mfupi ya mbinu hii -

740
00:31:36,030 --> 00:31:40,400
yaani recursion, kazi
kwamba kwa namna fulani wito yenyewe.

741
00:31:40,400 --> 00:31:44,780
>> Na tena, kukumbuka kwamba aina kuunganisha
pseudocode alikuwa kujirudia kwa maana ya

742
00:31:44,780 --> 00:31:48,460
kwamba moja ya hatua ya kuunganisha aina ya
mara kuwaita aina -

743
00:31:48,460 --> 00:31:49,740
kwamba ni, yenyewe.

744
00:31:49,740 --> 00:31:52,480
Bali nashiriki, kwa sababu sisi naendelea
wito aina, au kuunganisha aina,

745
00:31:52,480 --> 00:31:55,880
hasa, juu na ndogo ndogo
na ndogo orodha, sisi hatimaye

746
00:31:55,880 --> 00:32:00,005
bottomed nje shukrani kwa kile Tutamwita
kesi ya msingi, kesi ngumu-coded kwamba

747
00:32:00,005 --> 00:32:04,270
alisema kama orodha ni ndogo, chini ya 2
katika kesi hiyo, tu kurudi mara moja.

748
00:32:04,270 --> 00:32:07,550
Kama hatukuwa na kwamba kesi maalum,
algorithm ingekuwa kamwe chini nje,

749
00:32:07,550 --> 00:32:11,010
na wewe bila ya shaka kupata katika
usio kitanzi kweli milele.

750
00:32:11,010 --> 00:32:14,330
>> Lakini tuseme kwamba sisi alitaka sasa kuweka
baadhi ya idadi juu ya hili, tena, kwa kutumia n

751
00:32:14,330 --> 00:32:15,660
kama kawaida ya pembejeo.

752
00:32:15,660 --> 00:32:18,680
Na nilitaka kuuliza wewe, nini
wakati jumla ya kushiriki katika

753
00:32:18,680 --> 00:32:19,800
mbio kuunganisha aina?

754
00:32:19,800 --> 00:32:22,960
Au zaidi kwa ujumla, nini
gharama yake katika muda?

755
00:32:22,960 --> 00:32:24,730
>> Naam ni pretty rahisi kupima kwamba.

756
00:32:24,730 --> 00:32:29,010
Kama n ni chini ya 2, wakati husika
katika kuchagua mambo n,

757
00:32:29,010 --> 00:32:30,480
ambapo n ni 2, ni 0.

758
00:32:30,480 --> 00:32:31,410
Kwa sababu sisi tu kurudi.

759
00:32:31,410 --> 00:32:32,510
Hakuna kazi kufanyika.

760
00:32:32,510 --> 00:32:35,660
Sasa arguably, labda ni hatua moja au mbili
hatua kufikiri kiasi cha

761
00:32:35,660 --> 00:32:38,420
kazi, lakini ni karibu kutosha 0 kwamba
Mimi tu kwenda kusema hakuna kazi ni

762
00:32:38,420 --> 00:32:40,940
required kama orodha ni ndogo
kuwa uninteresting.

763
00:32:40,940 --> 00:32:42,580
>> Lakini kesi hii ni ya kuvutia.

764
00:32:42,580 --> 00:32:47,320
kesi ya kujirudia mara tawi la
pseudocode kwamba alisema mwingine, aina

765
00:32:47,320 --> 00:32:52,000
nusu ya kushoto, aina ya haki
nusu, kuunganisha nusu mbili.

766
00:32:52,000 --> 00:32:55,530
Sasa kwa nini msemo huu
kuwakilisha kwamba gharama?

767
00:32:55,530 --> 00:32:58,690
Naam, T ya n tu ina maana
wakati wa kuchambua mambo n.

768
00:32:58,690 --> 00:33:03,070
Na kisha upande wa kulia wa
alama ya usawa huko, T ya n kugawanywa

769
00:33:03,070 --> 00:33:06,600
na 2 ni akimaanisha gharama ya nini?

770
00:33:06,600 --> 00:33:07,570
Uamuzi nusu ya kushoto.

771
00:33:07,570 --> 00:33:10,990
T nyingine ya n kugawanywa na 2 ni
labda akimaanisha gharama

772
00:33:10,990 --> 00:33:12,390
kutatua nusu ya haki.

773
00:33:12,390 --> 00:33:14,590
>> Na kisha n pamoja?

774
00:33:14,590 --> 00:33:15,420
Ni kuunganisha.

775
00:33:15,420 --> 00:33:19,120
Kwa sababu kama una orodha mbili, moja ya
ukubwa n zaidi ya 2 na mwingine wa kawaida n

776
00:33:19,120 --> 00:33:22,580
zaidi ya 2, una kimsingi kugusa
kila moja ya mambo hayo, kama Rob

777
00:33:22,580 --> 00:33:24,990
kuguswa kila moja ya vikombe, na tu
kama sisi alisema katika kila moja ya

778
00:33:24,990 --> 00:33:26,310
kujitolea juu ya hatua.

779
00:33:26,310 --> 00:33:28,790
Hivyo n ni gharama ya kuunganisha.

780
00:33:28,790 --> 00:33:31,780
>> Sasa kwa bahati mbaya, hii formula
yenyewe pia ni kujirudia.

781
00:33:31,780 --> 00:33:36,390
Hivyo kama aliuliza swali, kama ni n, kusema,
16, kama kuna watu 16 juu ya hatua

782
00:33:36,390 --> 00:33:40,670
au 16 vikombe katika video, jinsi wengi taarifa
hatua gani kuchukua aina yao

783
00:33:40,670 --> 00:33:41,550
na aina kuunganisha?

784
00:33:41,550 --> 00:33:45,790
Ni kweli si jibu wazi,
kwa sababu sasa una aina ya

785
00:33:45,790 --> 00:33:48,500
recursively kujibu formula hii.

786
00:33:48,500 --> 00:33:51,190
>> Lakini hiyo ni sawa, kwa sababu napenda kupendekeza
kwamba sisi kufanya yafuatayo.

787
00:33:51,190 --> 00:33:56,670
wakati husika kutatua watu 16 au
16 vikombe ni kwenda kuwa kuwakilishwa

788
00:33:56,670 --> 00:33:58,020
ujumla kama T ya 16.

789
00:33:58,020 --> 00:34:01,400
Lakini hiyo ni sawa, kwa mujibu wa wetu
uliopita formula, 2 mara kiasi

790
00:34:01,400 --> 00:34:04,780
ya muda inachukua kutatua
8 vikombe pamoja na 16.

791
00:34:04,780 --> 00:34:08,590
Na tena, pamoja na 16 ni wakati wa kuunganisha,
na T mara mbili ya 8 ni

792
00:34:08,590 --> 00:34:10,790
wakati kutatua nusu kushoto na nusu ya haki.

793
00:34:10,790 --> 00:34:11,989
>> Lakini tena, hii si ya kutosha.

794
00:34:11,989 --> 00:34:13,210
Tuna kwa kupiga mbizi katika zaidi.

795
00:34:13,210 --> 00:34:16,409
Hii ina maana tuna kujibu
Swali, ni nini T ya 8?

796
00:34:16,409 --> 00:34:19,610
Vizuri Simu ya 8 ni 2 tu
mara Simu ya 4 pamoja na 8.

797
00:34:19,610 --> 00:34:20,520
Vizuri, nini T ya 4?

798
00:34:20,520 --> 00:34:23,780
Simu ya 4 ni mara 2 T ya 2 plus 4.

799
00:34:23,780 --> 00:34:25,489
Vizuri, nini T ya 2?

800
00:34:25,489 --> 00:34:29,030
Simu ya 2 ni mara 2 T ya 1 plus 2.

801
00:34:29,030 --> 00:34:31,940
>> Na tena, sisi ni aina ya kupata
kukwama katika mzunguko huu.

802
00:34:31,940 --> 00:34:34,790
Lakini ni kuhusu hit kwamba
kinachojulikana msingi kesi.

803
00:34:34,790 --> 00:34:37,310
Kwa sababu nini T ya 1, gani sisi kudai?

804
00:34:37,310 --> 00:34:37,810
0.

805
00:34:37,810 --> 00:34:39,730
Hivyo sasa hatimaye, tunaweza kufanya kazi kwa kurudi nyuma.

806
00:34:39,730 --> 00:34:44,290
>> Kama T ya 1 ni 0, mimi sasa wanaweza kwenda nyuma hadi moja
kujipanga na guy hii hapa, na siwezi

807
00:34:44,290 --> 00:34:46,330
kuziba katika 0 kwa T ya 1.

808
00:34:46,330 --> 00:34:51,770
Hivyo kwamba maana yake ni sawa na mara 2 sifuri,
inayojulikana kama 0, plus 2.

809
00:34:51,770 --> 00:34:53,739
Na ili kujieleza kwa ujumla ni 2.

810
00:34:53,739 --> 00:34:58,740
>> Sasa kama mimi kuchukua Simu ya 2, ambao jibu
ni 2, kuziba ndani ya mstari wa katikati, T

811
00:34:58,740 --> 00:35:02,740
ya 4, kwamba anatoa mimi mara 2
2 pamoja na 4, hivyo 8.

812
00:35:02,740 --> 00:35:07,080
Kama mimi kisha kuziba katika 8 kwa uliopita
mstari, kwamba anatoa mimi mara 2 8, 16.

813
00:35:07,080 --> 00:35:12,470
Na kama sisi kisha kuendelea kuwa na
24, na kuongeza katika 16, sisi hatimaye kupata

814
00:35:12,470 --> 00:35:13,820
thamani ya 64.

815
00:35:13,820 --> 00:35:18,480
>> Sasa kwa kuwa katika yenyewe aina ya anaongea
chochote kwa nukuu n,

816
00:35:18,480 --> 00:35:20,700
kubwa O, omega kwamba tumekuwa
imekuwa kuzungumza juu.

817
00:35:20,700 --> 00:35:24,890
Lakini zinageuka kuwa 64 kwa kweli ni
16, ukubwa wa pembejeo,

818
00:35:24,890 --> 00:35:27,110
kuingia wigo 2 ya 16.

819
00:35:27,110 --> 00:35:30,200
Na kama hii ni kidogo usio wa kawaida, tu
kufikiri nyuma, na kutakuwa na kuja nyuma

820
00:35:30,200 --> 00:35:30,700
na wewe hatimaye.

821
00:35:30,700 --> 00:35:33,775
Kama hii ni kwa logi msingi 2, ni kama 2
kufufuka kwa nini anatoa wewe 16?

822
00:35:33,775 --> 00:35:36,380
Oh, hiyo ni 4, hivyo ni 16 mara 4.

823
00:35:36,380 --> 00:35:39,380
>> Na tena, siyo mpango kubwa kama hii
ni aina ya kumbukumbu hazy sasa.

824
00:35:39,380 --> 00:35:43,720
Lakini kwa sasa, kuchukua imani
kwamba 16 logi 16 ni 64.

825
00:35:43,720 --> 00:35:46,590
Na hivyo kweli kweli, na sanity hii rahisi
kuangalia, tumekuwa alithibitisha -

826
00:35:46,590 --> 00:35:48,250
lakini si imeonekana rasmi -

827
00:35:48,250 --> 00:35:52,800
kwamba wakati mbio ya kuunganisha
aina ni kweli n logi n.

828
00:35:52,800 --> 00:35:53,790
>> Hivyo si mbaya.

829
00:35:53,790 --> 00:35:57,260
Ni dhahiri bora kuliko
algorithms tumeona hivi sasa, na

830
00:35:57,260 --> 00:36:00,710
ni kwa sababu tumekuwa leveraged, moja,
mbinu inayoitwa recursion.

831
00:36:00,710 --> 00:36:03,880
Lakini ya kuvutia zaidi kuliko hiyo, ya kwamba
dhana ya kugawa na mshindi.

832
00:36:03,880 --> 00:36:07,460
Tena, kweli wiki 0 mambo ambayo
hata sasa ni mara kwa mara katika

833
00:36:07,460 --> 00:36:08,740
zaidi ya kulazimisha njia.

834
00:36:08,740 --> 00:36:11,750
>> Sasa furaha kidogo zoezi, kama wameweza
kamwe kufanyika hii - na pengine

835
00:36:11,750 --> 00:36:14,660
bila kuwa, kwa sababu ya aina ya kawaida
watu sidhani kufanya hili.

836
00:36:14,660 --> 00:36:20,650
Lakini kama mimi nenda google.com na kama
Nataka kujifunza kitu kuhusu

837
00:36:20,650 --> 00:36:22,356
recursion, kuingia.

838
00:36:22,356 --> 00:36:25,106

839
00:36:25,106 --> 00:36:29,058
>> [Kicheko]

840
00:36:29,058 --> 00:36:32,030
[ZAIDI kicheko]

841
00:36:32,030 --> 00:36:33,385
DAVID Malan: utani Bad polepole kueneza.

842
00:36:33,385 --> 00:36:34,450
[Kicheko]

843
00:36:34,450 --> 00:36:36,970
DAVID Malan: Tu katika kesi, ni huko.

844
00:36:36,970 --> 00:36:38,710
Sikuweza Spell ni makosa,
na kuna mzaha.

845
00:36:38,710 --> 00:36:40,810
Wote haki.

846
00:36:40,810 --> 00:36:42,950
Kueleza ni watu wa karibu na wewe kama
bado kabisa clicked bado tu.

847
00:36:42,950 --> 00:36:47,650
Lakini kujirudia, kwa ujumla zaidi, inahusu
mchakato wa kazi ya wito

848
00:36:47,650 --> 00:36:51,430
yenyewe, au zaidi kwa ujumla, kugawa
tatizo katika kitu ambacho unaweza kuwa

849
00:36:51,430 --> 00:36:56,220
kutatuliwa piecemeal na kutatua kufanana
mwakilishi matatizo.

850
00:36:56,220 --> 00:36:58,400
>> Mabadiliko vizuri, hebu gia
kwa muda tu.

851
00:36:58,400 --> 00:37:00,840
Sisi kama mwisho juu ya cliffhangers fulani,
hivyo hebu kuanza kwa kuweka

852
00:37:00,840 --> 00:37:05,870
hatua, kwa dakika kadhaa,
juu ya wazo rahisi sana -

853
00:37:05,870 --> 00:37:07,620
ile ya swapping mambo mawili, haki?

854
00:37:07,620 --> 00:37:10,040
Yote ya algorithms haya tumekuwa
kuzungumza juu ya wanandoa wa zamani wa

855
00:37:10,040 --> 00:37:12,420
mihadhara kuhusisha baadhi ya
aina ya swapping.

856
00:37:12,420 --> 00:37:14,630
Leo ilikuwa Aliwazia na wao kupata
hadi nje ya viti vyao na

857
00:37:14,630 --> 00:37:18,570
kutembea karibu, lakini katika kanuni, tunataka
tu kuchukua kipengele kutoka safu moja

858
00:37:18,570 --> 00:37:20,370
na plop ndani ya mwingine.

859
00:37:20,370 --> 00:37:21,880
>> Hivyo ni jinsi gani sisi kwenda juu ya kufanya hii?

860
00:37:21,880 --> 00:37:24,850
Naam, napenda kwenda mbele na kuandika
mpango wa haraka hapa.

861
00:37:24,850 --> 00:37:31,600
Mimi nina kwenda mbele na kufanya
hii kama yafuatayo.

862
00:37:31,600 --> 00:37:33,910
Hebu piga hii -

863
00:37:33,910 --> 00:37:38,070
je, tunataka kuwaita hii moja?

864
00:37:38,070 --> 00:37:38,650
>> Kweli, hakuna.

865
00:37:38,650 --> 00:37:39,420
Hebu rewind.

866
00:37:39,420 --> 00:37:41,220
Sitaki kufanya hivyo
cliffhanger bado.

867
00:37:41,220 --> 00:37:42,270
Itakuwa nyara furaha.

868
00:37:42,270 --> 00:37:43,600
Hebu kufanya hivyo badala yake.

869
00:37:43,600 --> 00:37:47,430
>> Tuseme kwamba nataka kuandika kidogo
mpango na kwamba sasa unadhihirisha hii

870
00:37:47,430 --> 00:37:48,700
wazo la kujirudia.

871
00:37:48,700 --> 00:37:50,370
Mimi aina ya got mbele ya mimi nikiwa huko.

872
00:37:50,370 --> 00:37:51,420
Mimi nina kwenda kufanya yafuatayo.

873
00:37:51,420 --> 00:38:00,220
>> Kwanza, ni pamoja na ya haraka ya kiwango io.h,
vilevile ni pamoja na ya cs50.h.

874
00:38:00,220 --> 00:38:03,200
Na kisha mimi nina kwenda mbele
na kutangaza int kuu utupu

875
00:38:03,200 --> 00:38:04,360
katika njia ya kawaida.

876
00:38:04,360 --> 00:38:07,920
Nilitambua nimekuwa misnamed faili, hivyo
basi mimi tu kuongeza c. ugani hapa hivyo

877
00:38:07,920 --> 00:38:09,510
kwamba tunaweza kukusanya ni vizuri.

878
00:38:09,510 --> 00:38:10,970
Kuanza kazi huu mbali.

879
00:38:10,970 --> 00:38:13,290
>> Na kazi nataka kuandika, kabisa
tu, ni moja kwamba anauliza

880
00:38:13,290 --> 00:38:16,210
mtumiaji kwa ajili ya simu na kisha anaongeza hadi
idadi yote kati ya kuwa

881
00:38:16,210 --> 00:38:19,920
idadi na, kusema, 0.

882
00:38:19,920 --> 00:38:22,510
Hivyo kwanza mimi nina kwenda mbele
na kutangaza n int.

883
00:38:22,510 --> 00:38:24,760
Kisha mimi nakala baadhi ya kanuni kwamba
tumekuwa kutumika kwa muda.

884
00:38:24,760 --> 00:38:26,660
Wakati kitu ni kweli.

885
00:38:26,660 --> 00:38:28,000
Nitakuja nyuma na kwamba katika wakati huu.

886
00:38:28,000 --> 00:38:29,010
>> Nini mimi unataka kufanya nini?

887
00:38:29,010 --> 00:38:33,460
Mimi nataka kusema printf chanya
integer tafadhali.

888
00:38:33,460 --> 00:38:36,130
Na kisha mimi naenda
kusema n anapata kupata int.

889
00:38:36,130 --> 00:38:38,800
Hivyo tena, baadhi ya kanuni boilerplate
kwamba tumekuwa kutumika kabla.

890
00:38:38,800 --> 00:38:40,810
Na mimi nina kwenda kufanya hili
wakati n ni chini ya 1.

891
00:38:40,810 --> 00:38:44,120
Hivyo hii kuhakikisha kwamba mtumiaji
anitiaye sifuri.

892
00:38:44,120 --> 00:38:45,490
>> Na sasa mimi naenda kufanya yafuatayo.

893
00:38:45,490 --> 00:38:51,020
Nataka kuongeza hadi wote wa idadi ya
kati ya 1 na na n, au 0 na n,

894
00:38:51,020 --> 00:38:52,570
equivalently, kwa kupata jumla jumla.

895
00:38:52,570 --> 00:38:55,100
Hivyo kubwa sigma ishara
kwamba unaweza kukumbuka.

896
00:38:55,100 --> 00:38:59,050
Hivyo nina kwenda kufanya hili na wito wa kwanza
kazi kuitwa sigma,

897
00:38:59,050 --> 00:39:06,030
kupita katika n, na kisha mimi naenda
kusema printf, jibu ni haki pale.

898
00:39:06,030 --> 00:39:08,180
>> Hivyo katika muda mfupi, na mimi kupata
int kutoka kwa mtumiaji.

899
00:39:08,180 --> 00:39:09,280
Mimi kuhakikisha ni mazuri.

900
00:39:09,280 --> 00:39:12,700
Mimi kutangaza variable kuitwa jibu la
aina int na kuhifadhi katika ni kurudi

901
00:39:12,700 --> 00:39:15,610
thamani ya sigma, kupita katika n kama pembejeo.

902
00:39:15,610 --> 00:39:17,060
Na kisha mimi magazeti nje kwamba jibu.

903
00:39:17,060 --> 00:39:19,550
>> Kwa bahati mbaya, hata ingawa sigma sauti
kama kitu ambacho wanaweza kuwa katika

904
00:39:19,550 --> 00:39:24,040
faili math.h, tamko lake,
ni kweli si.

905
00:39:24,040 --> 00:39:24,690
Hivyo hiyo ni sawa.

906
00:39:24,690 --> 00:39:26,170
Siwezi kutekeleza hili mwenyewe.

907
00:39:26,170 --> 00:39:29,160
Mimi nina kwenda kutekeleza kazi kuitwa
sigma, na ni kwenda kuchukua

908
00:39:29,160 --> 00:39:29,900
parameter -

909
00:39:29,900 --> 00:39:32,100
hebu tu kuiita m, tu
hivyo ni tofauti.

910
00:39:32,100 --> 00:39:35,910
Na kisha hadi hapa, mimi nina kwenda kusema,
vizuri, kama m ni chini ya 1 - hii ni

911
00:39:35,910 --> 00:39:38,180
sana uninteresting mpango.

912
00:39:38,180 --> 00:39:41,700
Hivyo nina kwenda mbele na
mara moja kurudi 0.

913
00:39:41,700 --> 00:39:45,920
Ni tu haina maana kufanya kuongeza hadi kila
namba kati ya 1 na m kama m

914
00:39:45,920 --> 00:39:48,470
yenyewe ni 0 au hasi.

915
00:39:48,470 --> 00:39:50,900
>> Na kisha mimi nina kwenda mbele
na kufanya hili sana iteratively.

916
00:39:50,900 --> 00:39:53,090
Mimi nina kwenda kufanya aina hii ya umri wa shule ya-,
na mimi naenda kwa kwenda mbele

917
00:39:53,090 --> 00:39:57,150
na kusema kwamba mimi nina kwenda
Jumla kutangaza kuwa 0.

918
00:39:57,150 --> 00:39:59,630
Basi mimi naenda kuwa
kwa kitanzi cha int -

919
00:39:59,630 --> 00:40:02,820
na napenda kufanya hivyo kwa mechi yetu
usambazaji kificho, hivyo una nakala

920
00:40:02,820 --> 00:40:07,500
nyumbani. int i anapata 1 juu hadi
i ni chini ya au sawa na m.

921
00:40:07,500 --> 00:40:09,430
i pamoja plus.

922
00:40:09,430 --> 00:40:11,430
Na kisha ndani ya hii kwa kitanzi -

923
00:40:11,430 --> 00:40:12,440
tuko karibu huko -

924
00:40:12,440 --> 00:40:15,810
Jumla anapata Jumla pamoja na 1.

925
00:40:15,810 --> 00:40:17,670
Na basi mimi nina kwenda na kurudi jumla.

926
00:40:17,670 --> 00:40:19,420
>> Hivyo mimi alifanya hivyo haraka,
admittedly kabisa.

927
00:40:19,420 --> 00:40:22,775
Lakini tena, kazi kuu pretty
moja kwa moja, msingi juu ya kanuni tumekuwa

928
00:40:22,775 --> 00:40:23,190
imeandikwa hivi sasa.

929
00:40:23,190 --> 00:40:25,610
Anatumia kitanzi mbili kupata chanya
int kutoka kwa mtumiaji.

930
00:40:25,610 --> 00:40:29,870
Mimi kisha kupita kwamba int kwa kazi mpya
kuitwa sigma, wito ni, tena, n.

931
00:40:29,870 --> 00:40:33,100
Na mimi kuhifadhi thamani ya kurudi, jibu
kutoka sanduku nyeusi sasa

932
00:40:33,100 --> 00:40:35,460
inayojulikana kama sigma, katika kutofautiana
kuitwa jibu.

933
00:40:35,460 --> 00:40:36,580
Kisha mimi magazeti hayo.

934
00:40:36,580 --> 00:40:39,090
>> Kama sisi sasa kuendelea hadithi,
ni jinsi gani sigma kutekelezwa?

935
00:40:39,090 --> 00:40:40,840
Napendekeza kutekeleza kama ifuatavyo.

936
00:40:40,840 --> 00:40:43,560
Kwanza, kidogo kidogo ya makosa ya kuangalia-
kuhakikisha kwamba mtumiaji si

937
00:40:43,560 --> 00:40:46,480
messing na mimi na kupita katika
baadhi ya thamani hasi au 0.

938
00:40:46,480 --> 00:40:49,710
Basi mimi kutangaza variable kuitwa
sum na kuweka kwa 0.

939
00:40:49,710 --> 00:40:55,910
>> Na sasa mimi kuanza kutembea kutoka i sawa
1 njia yote hadi na pamoja na m,

940
00:40:55,910 --> 00:41:00,130
kwa sababu mimi nataka ni pamoja na kila
idadi kutoka moja kwa njia ya m, umoja.

941
00:41:00,130 --> 00:41:04,350
Na ndani ya hii kwa kitanzi, mimi tu kufanya
Jumla anapata chochote ni sasa, pamoja na

942
00:41:04,350 --> 00:41:08,900
thamani ya i.

943
00:41:08,900 --> 00:41:10,370
Plus thamani ya i.

944
00:41:10,370 --> 00:41:14,090
>> Kama kando, kama wameweza hawajaona hii
kabla, kuna baadhi ya sukari kisintaksia

945
00:41:14,090 --> 00:41:14,870
kwa ajili ya mstari huu.

946
00:41:14,870 --> 00:41:21,120
Siwezi kuandika tena kama plus sawa i,
tu kuokoa mwenyewe keystrokes chache

947
00:41:21,120 --> 00:41:22,570
na kuangalia baridi kidogo.

948
00:41:22,570 --> 00:41:23,140
Lakini hiyo yote.

949
00:41:23,140 --> 00:41:24,660
Ni functionally kitu kimoja.

950
00:41:24,660 --> 00:41:26,710
>> Bahati mbaya, hii kanuni ya
si kwenda kukusanya bado.

951
00:41:26,710 --> 00:41:31,600
Kama mimi kukimbia kufanya sigma 0, jinsi am
Mimi kwenda kupata yelled saa?

952
00:41:31,600 --> 00:41:33,473
Nini ni kwenda si kama?

953
00:41:33,473 --> 00:41:35,740
>> Watazamaji: [inaudible].

954
00:41:35,740 --> 00:41:37,800
>> DAVID Malan: Yeah, mimi hakuwa kutangaza
kazi juu juu, haki?

955
00:41:37,800 --> 00:41:40,590
C ni aina ya kijinga, kwa kuwa tu
anafanya nini kuwaambia ni nini, na wewe

956
00:41:40,590 --> 00:41:41,880
kufanya hivyo ili.

957
00:41:41,880 --> 00:41:45,910
Na hivyo kama mimi hit Enter hapa, mimi naenda
kupata onyo kuhusu sigma thabiti

958
00:41:45,910 --> 00:41:46,860
tamko.

959
00:41:46,860 --> 00:41:48,120
>> Oh, si tatizo.

960
00:41:48,120 --> 00:41:50,370
Naweza kwenda hadi juu, na siwezi
kusema, haki ya wote, kusubiri dakika.

961
00:41:50,370 --> 00:41:54,240
Sigma ni kazi kwamba anarudi
int na inatarajia

962
00:41:54,240 --> 00:41:56,620
int kama pembejeo semicolon,.

963
00:41:56,620 --> 00:41:59,550
Au mimi naweza kuweka kazi nzima
juu kuu, lakini kwa ujumla, ningependa

964
00:41:59,550 --> 00:42:02,260
kupendekeza dhidi ya kwamba, kwa sababu ni
nzuri daima kuwa na kuu kwa juu ili

965
00:42:02,260 --> 00:42:06,310
unaweza kupiga mbizi haki na kujua nini
mpango anafanya kwa kusoma kuu ya kwanza.

966
00:42:06,310 --> 00:42:07,930
>> Hivyo sasa napenda wazi screen.

967
00:42:07,930 --> 00:42:09,330
Umerudiwa sigma 0.

968
00:42:09,330 --> 00:42:10,340
Yote inaonekana kuangalia nje.

969
00:42:10,340 --> 00:42:11,970
Basi mimi kukimbia sigma 0.

970
00:42:11,970 --> 00:42:12,770
Chanya inter.

971
00:42:12,770 --> 00:42:15,580
Mimi nitakupa ni idadi
3 kushika ni rahisi.

972
00:42:15,580 --> 00:42:18,710
Hivyo kwamba wanapaswa kunipa 3
plus 2 pamoja na 1, hivyo 6.

973
00:42:18,710 --> 00:42:20,750
Kuingia, na kwa kweli mimi kupata 6.

974
00:42:20,750 --> 00:42:21,820
>> Mimi siwezi kufanya jambo kubwa -

975
00:42:21,820 --> 00:42:24,080
50, 12, 75.

976
00:42:24,080 --> 00:42:27,690
Tu kama tangent, mimi naenda kufanya
kitu ujinga kama kweli kubwa

977
00:42:27,690 --> 00:42:30,375
simu, Oh, kwamba kweli kazi nje -

978
00:42:30,375 --> 00:42:31,600
eh, sidhani kwamba ni sahihi.

979
00:42:31,600 --> 00:42:32,810
Hebu angalia.

980
00:42:32,810 --> 00:42:34,060
Hebu kweli fujo na hivyo.

981
00:42:34,060 --> 00:42:37,150

982
00:42:37,150 --> 00:42:38,400
>> Kwamba ni tatizo.

983
00:42:38,400 --> 00:42:43,180

984
00:42:43,180 --> 00:42:44,970
Nini kinaendelea?

985
00:42:44,970 --> 00:42:46,050
kanuni ya kuwa mbaya.

986
00:42:46,050 --> 00:42:48,470
Ni bado linear.

987
00:42:48,470 --> 00:42:50,810
Whistling ni athari nzuri, ingawa.

988
00:42:50,810 --> 00:42:52,060
Nini kinaendelea?

989
00:42:52,060 --> 00:42:54,700

990
00:42:54,700 --> 00:42:55,620
>> Uhakika kama mimi walisikia maneno hayo.

991
00:42:55,620 --> 00:42:57,620
Hivyo ni zamu nje - na
hii ni kama kando.

992
00:42:57,620 --> 00:42:59,400
Hii si ya msingi na
wazo la kujirudia.

993
00:42:59,400 --> 00:43:02,480
Ni zamu ya nje, kwa sababu mimi nina kujaribu
kuwakilisha idadi kubwa kama hiyo, wengi

994
00:43:02,480 --> 00:43:06,980
uwezekano ni kuwa misinterpreted
na C kama idadi si chanya,

995
00:43:06,980 --> 00:43:09,980
lakini hasi idadi.

996
00:43:09,980 --> 00:43:12,690
>> Sisi si aliongea kuhusu hili, lakini ni
zinageuka kuna idadi hasi

997
00:43:12,690 --> 00:43:14,210
katika dunia kwa kuongeza
kwa idadi chanya.

998
00:43:14,210 --> 00:43:16,290
Na njia ambayo unaweza
kuwakilisha idadi hasi

999
00:43:16,290 --> 00:43:19,530
kimsingi ni, unaweza kutumia moja
maalum kidogo zinaonyesha

1000
00:43:19,530 --> 00:43:20,400
mazuri zaidi ya hasi.

1001
00:43:20,400 --> 00:43:22,950
Ni kidogo ngumu zaidi kuliko kuwa,
lakini hiyo ni wazo msingi.

1002
00:43:22,950 --> 00:43:26,740
>> Hivyo kwa bahati mbaya, kama C ni utata moja
ya wale bits kama kweli maana,

1003
00:43:26,740 --> 00:43:30,790
oh, hii ni idadi hasi, kitanzi yangu
hapa, kwa mfano, ni kweli kamwe

1004
00:43:30,790 --> 00:43:31,740
kwenda kusitisha.

1005
00:43:31,740 --> 00:43:33,850
Hivyo kama mimi walikuwa kweli kitu kuchapa
tena na tena, tunataka

1006
00:43:33,850 --> 00:43:34,650
kuona mengi nzima.

1007
00:43:34,650 --> 00:43:36,220
Lakini tena, hii ni badala ya uhakika.

1008
00:43:36,220 --> 00:43:38,590
Hii ni kweli tu aina ya
miliki udadisi kwamba tutaweza kuja

1009
00:43:38,590 --> 00:43:39,550
nyuma na hatimaye.

1010
00:43:39,550 --> 00:43:43,400
Lakini kwa sasa, hii ni sahihi
utekelezaji kama sisi kudhani kwamba

1011
00:43:43,400 --> 00:43:45,970
mtumiaji itatoa ints
kwamba inafaa ndani ints.

1012
00:43:45,970 --> 00:43:49,370
>> Lakini mimi kudai kwamba kanuni hii, kusema ukweli,
inaweza kufanyika hivyo zaidi tu.

1013
00:43:49,370 --> 00:43:54,060
Kama lengo katika mkono ni kuchukua simu
kama m na kuongeza hadi yote ya

1014
00:43:54,060 --> 00:43:59,510
idadi kati yake na 1, au kinyume chake
kati ya 1 na hayo, mimi kudai

1015
00:43:59,510 --> 00:44:03,380
kwamba naweza kukopa wazo hili kwamba kuunganisha
aina alikuwa, ambayo ilikuwa kuchukua tatizo

1016
00:44:03,380 --> 00:44:05,660
hii ya kawaida na kugawa
katika kitu kidogo.

1017
00:44:05,660 --> 00:44:09,875
Labda si nusu, lakini vidogo, lakini
representatively sawa.

1018
00:44:09,875 --> 00:44:12,130
Same wazo, lakini tatizo kidogo.

1019
00:44:12,130 --> 00:44:15,470
>> Hivyo mimi nina kweli - basi mimi kuokoa faili hii
na idadi tofauti version.

1020
00:44:15,470 --> 00:44:17,670
Tutamwita toleo hili
1 badala ya 0.

1021
00:44:17,670 --> 00:44:20,790
Na mimi kudai kwamba naweza kweli
reimplement hii katika aina hii ya

1022
00:44:20,790 --> 00:44:22,160
akili-bending njia.

1023
00:44:22,160 --> 00:44:23,710
>> Mimi naenda kuondoka sehemu ya peke yake.

1024
00:44:23,710 --> 00:44:27,710
Mimi nina kwenda kusema kama m ni chini
kuliko au hata sawa na 0 -

1025
00:44:27,710 --> 00:44:29,280
Mimi tu kwenda kuwa kidogo
zaidi anal wakati huu

1026
00:44:29,280 --> 00:44:30,520
na makosa yangu kuangalia -

1027
00:44:30,520 --> 00:44:33,190
Mimi nina kwenda mbele na kurudi 0.

1028
00:44:33,190 --> 00:44:34,490
Hii ni holela.

1029
00:44:34,490 --> 00:44:37,500
Mimi tu tu kuamua kama mtumiaji
anitiaye simu hasi, mimi nina

1030
00:44:37,500 --> 00:44:41,490
kurudi 0, na wao wanapaswa kuwa na kusoma
nyaraka kwa karibu zaidi.

1031
00:44:41,490 --> 00:44:42,170
>> Kingine -

1032
00:44:42,170 --> 00:44:44,070
taarifa ya nini mimi nina kwenda kufanya.

1033
00:44:44,070 --> 00:44:49,260
Mwingine mimi kwenda na kurudi m plus -

1034
00:44:49,260 --> 00:44:51,010
ni nini sigma ya m?

1035
00:44:51,010 --> 00:44:56,710
Naam, sigma ya m plus minus m 1,
pamoja na m bala 2, pamoja na m bala 3.

1036
00:44:56,710 --> 00:44:58,030
Sitaki kuandika yote ya nje kwamba.

1037
00:44:58,030 --> 00:44:59,120
Kwa nini si mimi tu Punt?

1038
00:44:59,120 --> 00:45:05,080
Recursively kuwaita mwenyewe na kidogo
ndogo tatizo, semicolon,

1039
00:45:05,080 --> 00:45:06,840
na kuiita siku?

1040
00:45:06,840 --> 00:45:07,040
>> Haki?

1041
00:45:07,040 --> 00:45:10,980
Sasa hapa, pia, unaweza kuhisi au wasiwasi
kwamba hii ni kitanzi usio kwamba mimi nina

1042
00:45:10,980 --> 00:45:15,450
inducing, ambapo mimi ni kutekeleza
sigma na wito sigma.

1043
00:45:15,450 --> 00:45:20,342
Lakini hiyo ni kikamilifu sawa, kwa sababu mimi
walidhani mbele aliongeza mistari ambayo?

1044
00:45:20,342 --> 00:45:22,600
>> Watazamaji: [inaudible].

1045
00:45:22,600 --> 00:45:25,430
>> DAVID Malan: 23 na 26, ambayo
ni wangu kama hali hiyo.

1046
00:45:25,430 --> 00:45:28,390
Kwa sababu nini ni nzuri kuhusu
kutoa hapa, kwa sababu mimi kuendelea

1047
00:45:28,390 --> 00:45:31,180
kuwapatia sigma ndogo matatizo, ndogo
matatizo, ndogo - si

1048
00:45:31,180 --> 00:45:31,870
ukubwa wa nusu.

1049
00:45:31,870 --> 00:45:34,380
Ni hatua tu mtoto ndogo,
lakini hiyo ni sawa.

1050
00:45:34,380 --> 00:45:38,050
Kwa sababu hatimaye, tutaweza kazi
njia yetu chini ya 1 au 0.

1051
00:45:38,050 --> 00:45:41,630
Na mara moja sisi hit 0, sigma si
kwenda kuwaita yenyewe tena.

1052
00:45:41,630 --> 00:45:43,590
Ni kwenda mara moja kurudi 0.

1053
00:45:43,590 --> 00:45:47,960
>> Hivyo athari, kama aina ya upepo huu
juu katika akili yako, ni kuongeza m pamoja

1054
00:45:47,960 --> 00:45:52,740
m minus 1, pamoja na m bala 2, pamoja na m bala
3, pamoja na dot, dot, dot, bala m

1055
00:45:52,740 --> 00:45:57,820
m, hatimaye kutoa 0, na
athari ni hatimaye kuongeza yote ya

1056
00:45:57,820 --> 00:45:59,070
mambo haya kwa pamoja.

1057
00:45:59,070 --> 00:46:02,380
Hivyo hatuna, na kujirudia,
kutatuliwa tatizo kwamba sisi

1058
00:46:02,380 --> 00:46:03,470
hakuweza kutatua kabla.

1059
00:46:03,470 --> 00:46:06,840
Hakika, toleo 0 wa hii, na kila
tatizo hadi sasa, imekuwa solvable

1060
00:46:06,840 --> 00:46:09,980
na kutumia tu kwa tanzi au wakati
mizunguko au constructs sawa.

1061
00:46:09,980 --> 00:46:13,150
>> Lakini recursion, mimi daresay, inatupa
njia tofauti wa kufikiri kuhusu

1062
00:46:13,150 --> 00:46:17,010
matatizo, ambapo kama tunaweza kuchukua
tatizo, kuigawanya kutoka kitu

1063
00:46:17,010 --> 00:46:22,340
kubwa kiasi fulani katika kitu fulani
ndogo, mimi kudai kwamba tunaweza kutatua hilo

1064
00:46:22,340 --> 00:46:26,040
labda kidogo zaidi elegantly katika suala
ya kubuni, na kanuni ya chini,

1065
00:46:26,040 --> 00:46:30,980
na labda hata kutatua matatizo ambayo ingekuwa
kuwa ngumu, kama tutaweza hatimaye

1066
00:46:30,980 --> 00:46:33,280
kuona, kutatua rena iteratively.

1067
00:46:33,280 --> 00:46:35,980
>> Lakini cliffhanger kwamba mimi
wanataka kuondoka sisi juu ilikuwa hii.

1068
00:46:35,980 --> 00:46:40,720
Hebu kwenda mbele na kufungua
hadi faili kutoka -

1069
00:46:40,720 --> 00:46:44,300
kweli, napenda kwenda na
kufanya hivyo kwa haraka kweli.

1070
00:46:44,300 --> 00:46:46,875
Hebu kwenda mbele na kupendekeza
zifuatazo.

1071
00:46:46,875 --> 00:46:51,160

1072
00:46:51,160 --> 00:46:54,785
Miongoni mwa kanuni ya leo ni faili hii hapa.

1073
00:46:54,785 --> 00:47:01,090

1074
00:47:01,090 --> 00:47:03,050
Hii moja hapa, noswap.

1075
00:47:03,050 --> 00:47:06,260
>> Hivyo hii ni ya kijinga kidogo mpango kwamba
Mimi kuchapwa up kuwa madai ya kufanya

1076
00:47:06,260 --> 00:47:06,940
zifuatazo.

1077
00:47:06,940 --> 00:47:10,140
Katika kuu, ni ya kwanza anatangaza
int kuitwa x na inateua ni

1078
00:47:10,140 --> 00:47:11,100
thamani ya 1.

1079
00:47:11,100 --> 00:47:13,520
Kisha inatangaza y int na
inateua ni thamani 2.

1080
00:47:13,520 --> 00:47:15,310
Basi ni Prints nje nini x na y ni.

1081
00:47:15,310 --> 00:47:17,781
Kisha anasema, swapping, dot dot dot.

1082
00:47:17,781 --> 00:47:21,670
>> Basi ni madai kuwa wito kazi
kuitwa wabadilishane, kupita katika x na

1083
00:47:21,670 --> 00:47:24,290
y, wazo la ambayo ni kwamba hopefully
x na y atakuja tena

1084
00:47:24,290 --> 00:47:25,620
tofauti, kinyume.

1085
00:47:25,620 --> 00:47:27,110
Basi ni kudai walibadilishana!

1086
00:47:27,110 --> 00:47:28,420
na kumweka Moderators.

1087
00:47:28,420 --> 00:47:30,190
Basi ni Prints nje x na y.

1088
00:47:30,190 --> 00:47:33,480
>> Lakini zinageuka kuwa hii sana
rahisi maandamano chini

1089
00:47:33,480 --> 00:47:35,570
hapa ni kweli Buggy.

1090
00:47:35,570 --> 00:47:38,870
Hata mimi nina kutangaza muda
kutofautiana na muda kuweka katika

1091
00:47:38,870 --> 00:47:42,010
hivyo, basi mimi nina reassigning
thamani ya b -

1092
00:47:42,010 --> 00:47:45,080
ambayo anahisi nzuri, kwa sababu nimekuwa
nakala ya kuokolewa katika temp.

1093
00:47:45,080 --> 00:47:48,410
Kisha mimi update b sawa
chochote kilichokuwa katika temp.

1094
00:47:48,410 --> 00:47:51,610
Aina hii ya mchezo shell ya kusonga
ndani ya b na b ndani ya hii kwa kutumia

1095
00:47:51,610 --> 00:47:54,360
katikati-mtu mmoja aitwaye temp anahisi
kikamilifu busara.

1096
00:47:54,360 --> 00:47:57,270
>> Lakini mimi kudai kwamba wakati mimi kukimbia hii
kanuni, kama mimi itabidi kufanya sasa -

1097
00:47:57,270 --> 00:47:59,490
napenda kwenda mbele na kuweka katika hapa.

1098
00:47:59,490 --> 00:48:01,995
Mimi nitakuita hii noswap.c.

1099
00:48:01,995 --> 00:48:05,630
Na kama jina linavyosema, hii si
kwenda kuwa mpango sahihi.

1100
00:48:05,630 --> 00:48:09,460
Kufanya noswap /. Hakuna kubadilishana.

1101
00:48:09,460 --> 00:48:12,110
x ni 1, y ni 2, swapping, walibadilishana.

1102
00:48:12,110 --> 00:48:14,220
x ni 1, y ni 2.

1103
00:48:14,220 --> 00:48:16,920
Kimsingi hili ni vibaya, hata
ingawa hii inaonekana kikamilifu

1104
00:48:16,920 --> 00:48:17,730
busara kwangu.

1105
00:48:17,730 --> 00:48:21,330
Na kuna sababu, lakini sisi siyo
kwenda yatangaza sababu bado tu.

1106
00:48:21,330 --> 00:48:24,610
>> Kwa sasa cliffhanger pili nilitaka
kuondoka na ni hii,

1107
00:48:24,610 --> 00:48:27,120
tangazo la aina ya Coupon namba.

1108
00:48:27,120 --> 00:48:31,590
Ubunifu wetu na siku mwishoni mwa mwaka huu
umesababisha idadi zisizo yasiyo na maana

1109
00:48:31,590 --> 00:48:33,830
ya maswali, ambayo ilikuwa
Si nia yetu.

1110
00:48:33,830 --> 00:48:36,590
Nia ya kanuni hizi Coupon,
ambapo kama wewe kufanya sehemu ya tatizo

1111
00:48:36,590 --> 00:48:39,850
kuweka mapema, na hivyo kupata siku ya ziada,
alikuwa kweli kukusaidia guys kusaidia

1112
00:48:39,850 --> 00:48:42,420
mwenyewe kuanza mapema, aina
wa na incentivizing wewe.

1113
00:48:42,420 --> 00:48:44,880
Inatusaidia kusambaza mzigo hela
masaa ya ofisi bora ili

1114
00:48:44,880 --> 00:48:45,740
ni aina ya kushinda na kushinda.

1115
00:48:45,740 --> 00:48:48,860
>> Kwa bahati mbaya, nadhani maagizo yangu
wamekuwa, hadi sasa, wazi sana, hivyo

1116
00:48:48,860 --> 00:48:52,230
Mimi kurudi mwishoni mwa wiki hii na updated
spec katika maandishi kubwa, bolder kwa

1117
00:48:52,230 --> 00:48:53,600
kueleza risasi kama hizi.

1118
00:48:53,600 --> 00:48:56,900
Na tu kusema hivyo zaidi ya hadharani, na
default, tatizo seti ni kutokana Alhamisi

1119
00:48:56,900 --> 00:48:58,400
saa sita mchana, kwa mtaala.

1120
00:48:58,400 --> 00:49:02,030
Kama kuanza mapema, kumaliza sehemu ya
tatizo kuweka na Jumatano saa 12:00

1121
00:49:02,030 --> 00:49:05,170
PM, sehemu ambayo inahusiana na Coupon
kanuni, wazo ni kwamba unaweza kupanua

1122
00:49:05,170 --> 00:49:07,710
tarehe ya mwisho yako kwa ajili ya
P kuweka mpaka Ijumaa.

1123
00:49:07,710 --> 00:49:10,890
Hiyo ni, kidogo mbali sehemu ndogo ya P
kuweka jamaa na nini kawaida ni

1124
00:49:10,890 --> 00:49:13,200
kubwa tatizo, na kununua
mwenyewe siku ya ziada.

1125
00:49:13,200 --> 00:49:15,190
Tena, anapata wewe kufikiria juu ya
kuweka tatizo, anapata wewe

1126
00:49:15,190 --> 00:49:16,380
masaa ya ofisi mapema.

1127
00:49:16,380 --> 00:49:20,670
Lakini kanuni Coupon tatizo bado
inavyotakiwa, hata kama huna kuwasilisha.

1128
00:49:20,670 --> 00:49:23,340
>> Lakini zaidi compellingly ni hii.

1129
00:49:23,340 --> 00:49:26,520
(STAGE Whisper) Na wale folks kuacha
mapema ni gonna majuto.

1130
00:49:26,520 --> 00:49:28,620
Kama ni folks kwenye balcony.

1131
00:49:28,620 --> 00:49:32,510
Mimi kuomba msamaha mapema kwa folks juu ya
balcony kwa sababu hiyo itakuwa

1132
00:49:32,510 --> 00:49:33,920
wazi katika muda tu.

1133
00:49:33,920 --> 00:49:37,050
>> Hivyo sisi ni bahati ya kuwa moja ya
CS50 aliyekuwa mkuu mafundisho wenzake katika

1134
00:49:37,050 --> 00:49:39,302
kampuni inayoitwa dropbox.com.

1135
00:49:39,302 --> 00:49:45,500
Wao sana kwa ukarimu walichangia
Coupon code hapa kwa ajili ya nafasi hii sana,

1136
00:49:45,500 --> 00:49:48,180
ambayo ni juu kutoka
kawaida 2 gigabytes.

1137
00:49:48,180 --> 00:49:51,740
Hivyo nilifikiri nini tunataka kufanya juu ya hii
kumbuka mwisho ni kufanya kidogo ya giveaway,

1138
00:49:51,740 --> 00:49:55,380
ambapo katika muda tu, sisi itaonyesha
mshindi na ambaye ana Coupon

1139
00:49:55,380 --> 00:49:57,980
kificho kwamba unaweza kisha kwenda zao
tovuti, aina yake katika, na voilà, kupata

1140
00:49:57,980 --> 00:50:01,370
nzima mengi zaidi Dropbox nafasi kwa ajili yako
appliance na kwa files yako binafsi.

1141
00:50:01,370 --> 00:50:05,690
>> Na kwanza, ambao wangependa kushiriki
katika picha hii?

1142
00:50:05,690 --> 00:50:09,630
OK, sasa kwamba inafanya hata furaha zaidi.

1143
00:50:09,630 --> 00:50:14,010
mtu ambaye anapata hii gigabyte 25-
Coupon code - ambayo ni mbali

1144
00:50:14,010 --> 00:50:16,150
zaidi ya kulazimisha kuliko marehemu
siku sasa, labda -

1145
00:50:16,150 --> 00:50:20,620
ni mmoja ambaye ni ameketi juu ya
kiti cha mto zipitazo kuna

1146
00:50:20,620 --> 00:50:21,620
kwamba kanuni Coupon.

1147
00:50:21,620 --> 00:50:23,480
Unaweza sasa kuangalia chini ya
kiti yako mto.

1148
00:50:23,480 --> 00:50:28,710

1149
00:50:28,710 --> 00:50:29,680
>> [Video avspelning]

1150
00:50:29,680 --> 00:50:31,620
>> -Moja, mbili, tatu.

1151
00:50:31,620 --> 00:50:35,015
>> [WAKIPIGA KELELE]

1152
00:50:35,015 --> 00:50:35,985
>> -Unaweza kupata gari!

1153
00:50:35,985 --> 00:50:36,670
Unaweza kupata gari!

1154
00:50:36,670 --> 00:50:37,970
>> DAVID Malan: Tutaona
wewe juu ya Jumatano.

1155
00:50:37,970 --> 00:50:38,904
>> -Unaweza kupata gari!

1156
00:50:38,904 --> 00:50:39,371
Unaweza kupata gari!

1157
00:50:39,371 --> 00:50:40,305
Unaweza kupata gari!

1158
00:50:40,305 --> 00:50:41,706
Unaweza kupata gari!

1159
00:50:41,706 --> 00:50:43,107
Unaweza kupata gari!

1160
00:50:43,107 --> 00:50:45,530
>> DAVID Malan: Balcony folks, kuja
chini hapa mbele,

1161
00:50:45,530 --> 00:50:46,866
ambapo tuna extras.

1162
00:50:46,866 --> 00:50:50,282
>> -Kila mtu anapata gari!

1163
00:50:50,282 --> 00:50:52,234
Kila mtu anapata gari!

1164
00:50:52,234 --> 00:50:52,722
>> [MWISHO video avspelning]

1165
00:50:52,722 --> 00:50:54,590
>> NARRATOR: CS50 ijayo -

1166
00:50:54,590 --> 00:51:00,374
>> SPIKA 5: Oh gosh wangu gosh gosh gosh
gosh gosh gosh gosh gosh gosh -

1167
00:51:00,374 --> 00:51:02,106
>> [UKELELE ina]