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00:00:00,000 --> 00:00:10,940

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00:00:10,940 --> 00:00:13,060
>> DAVID J Malan: zote
haki, hivyo hii ni CS50.

3
00:00:13,060 --> 00:00:15,040
Na hii ni wazi siku ya Ijumaa.

4
00:00:15,040 --> 00:00:16,850
Na hii ni mwisho wa wiki moja.

5
00:00:16,850 --> 00:00:21,020
Hivyo unaweza kukumbuka kuwa sisi kushoto mbali,
Mara ya mwisho, na cliffhanger ya kila aina.

6
00:00:21,020 --> 00:00:25,020
Ambapo sisi kuweka wazi uongo huu, kwamba hakuna
jambo gani tumekuwa kufundishwa kuongezeka

7
00:00:25,020 --> 00:00:31,610
up, 1 kugawanywa na 10 ni siyo, katika
kweli, 0.1 au 0.100 au 0.10000.

8
00:00:31,610 --> 00:00:35,270
Kwa kweli, kama sisi kukusanya hii
mpango, kama tulivyofanya jana, na,

9
00:00:35,270 --> 00:00:39,770
kufanya kutokuwa sahihi, na kisha
kufanya dot, kufyeka, kutokuwa sahihi,

10
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tuligundua kwamba hii ni nini
1 kugawanywa na 10 kweli ni.

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00:00:43,600 --> 00:00:46,140
Hivyo hiyo ni kweli si kesi kabisa.

12
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Lakini hii haina ladha katika baadhi
msingi kiwango cha juu ya kompyuta.

13
00:00:49,014 --> 00:00:50,930
Na hakika, miongoni mwa
mambo tunakwenda kufanya

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00:00:50,930 --> 00:00:55,130
leo ni kuangalia nini hii ina
kilichotokea, ni nini maana ya hii ina,

15
00:00:55,130 --> 00:00:58,430
jinsi ya ubinadamu imeshindwa
kufahamu hii katika baadhi sana

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situations-- kubwa
matokeo yake ni kwamba

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imekuwa ya kutisha kabisa
na expensive-- na pia

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00:01:03,141 --> 00:01:04,849
kuangalia jinsi sisi
kweli anaweza kutetea

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00:01:04,849 --> 00:01:06,530
dhidi ya aina hii ya mapungufu.

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00:01:06,530 --> 00:01:10,940
Hivyo intuitively, labda,
nini 1 kugawanywa na 10,

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kwa mujibu wa kompyuta yangu
hapa, si tu 10/1, 0.10?

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Naam.

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Je, unafikiri?

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>> Watazamaji MEMBER: radix ni tofauti?

25
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>> DAVID J Malan: ni nini?

26
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Loo, radix ni tofauti?

27
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Hivyo si kabisa.

28
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Ni kweli zaidi
msingi kwa vifaa.

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Mawazo mengine?

30
00:01:23,980 --> 00:01:24,584
Naam.

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Watazamaji MEMBER: Wao
kuwakilisha idadi tofauti?

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DAVID J Malan: Hivyo they-- Haki.

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Wao kuwakilisha idadi tofauti.

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Inaccurately, inaonekana.

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Ili is-- Naam,
tofauti na nini?

36
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Au kutoka kwa nani?

37
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Kutoka kwetu?

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Watazamaji MEMBER: Naam.

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Hawana matumizi alisema
mfumo wa [inaudible].

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DAVID J Malan: Sawa.

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Hivyo kwa mantiki, hawana
kutumia mfumo alisema.

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Chini ya Hood,
kila kitu ni kweli, mapacha,

43
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na kwamba kuhusiana, kwa kweli.

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Lakini ni rahisi hata
maelezo ya hapo.

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Naam.

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>> Watazamaji MEMBER: Wao
tu na vipande wengi.

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Wanaweza tu kuhifadhi hadi fulani
kiasi, kama na decimals.

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>> DAVID J Malan: Yeah.

49
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Hii ni nini kweli kupata saa yake.

50
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Ni zinageuka kuwa kompyuta
kawaida, daima tu

51
00:01:57,180 --> 00:01:59,690
kutumia kiasi kidogo cha habari
kuiwakilisha kitu.

52
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Sawa?

53
00:01:59,870 --> 00:02:02,110
Baada ya yote, sisi tu fasta
kiasi cha nafasi ngumu disk.

54
00:02:02,110 --> 00:02:04,210
Sisi tu kuwa na kiasi fasta
ya RAM, au kumbukumbu ya kompyuta.

55
00:02:04,210 --> 00:02:06,251
Na kama wewe tu
fasta kiasi ya kitu,

56
00:02:06,251 --> 00:02:09,611
Hakika huwezi kweli kuhesabu hadi
infinity au idadi yoyote unataka.

57
00:02:09,611 --> 00:02:11,610
Wewe, aina ya, na
kuchukua na kuchagua kile mbalimbali

58
00:02:11,610 --> 00:02:13,220
ya maadili wewe ni kwenda kusaidia.

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>> Na hivyo kwa mfano, wiki moja au mbili
iliyopita, wakati kuongelea ASCII,

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na kuongelea 8 bits,
au Byte, hivyo kusema,

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idadi kubwa tunaweza
kuwakilisha na 8 bits ilikuwa nini?

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255.

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Na tunaweza kuwakilisha maadili 256 jumla
lakini si kama sisi kutumia mmoja wao

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juu ya 0-- Naam, lakini kama sisi
kutumia mmoja wao juu ya 0,

65
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basi idadi kubwa
Ni, bila shaka, 255.

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>> Hivyo ni zamu nje, kwamba hii ni
kesi pia, katika mazingira haya.

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Sisi kuanza kuzungumza, mara ya mwisho,
kuhusu idadi floating-kumweka, ambayo

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ni tofauti na integers, katika
kwamba wana uhakika decimal

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na, hopefully, baadhi idadi
baada ya kuwa, lakini wao ni pia.

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Kompyuta ni tu kawaida kwenda
kutumia bits 32, labda 64 bits

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kuiwakilisha floating kumweka thamani.

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Hivyo hata kama tumekuwa mzima
kujifunza hisabati na kujua

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uweze kabisa kuwa
idadi ya usio wa namba za

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baada ya uhakika decimal, si
kama una mahususi kumbukumbu.

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Wewe, aina ya, na kwa pande zote,
au kuchukua na kuchagua ambayo

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00:03:03,930 --> 00:03:05,346
idadi wewe ni kwenda kuwakilisha.

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Na hivyo unaweza kufikiria, kwa maana,
hili kuwa kompyuta wa karibu

78
00:03:08,710 --> 00:03:14,050
makadirio ya thamani 1/10 kwamba
inaweza kupata, na bits 32 tu au hivyo.

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Na si 1/10 tu.

80
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>> Kwa mfano, kama mimi kubadili hali hii kwa
1/3, ambayo tunafikiri ni hata rahisi.

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Hivyo 1 kugawanywa na 3.

82
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Hebu kuokoa faili.

83
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Hebu kwenda mbele na recompile yake.

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Na napenda re-kukimbia nayo.

85
00:03:25,820 --> 00:03:30,000
Hapa pia, inaonekana, 1/3 siyo 0.3
na kisha idadi ya usio wa 3 wa

86
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baada ya hapo.

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Una kutokuwa sahihi hii mwishoni.

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Hivyo sisi wanadamu ni sahihi, na kile
wewe kujifunza ni, kwa kweli, sahihi,

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lakini sisi ni bumping up
dhidi ya baadhi ya mapungufu.

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>> Na nini Nilidhani
tunatarajia kufanya leo, ni kuanza

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kwa kuangalia, kusema ukweli,
matokeo ya kutisha ya hii

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wakati mwingine, wakati mwanadamu
haina kabisa kutekeleza

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kwa ukweli huu na mapungufu hayo.

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Na tutaweza kuona mfululizo wa vignettes
kutoka Channel Historia kwamba inachukua

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kuangalia jinsi mambo wamekwenda vibaya.

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Ni kuhusu 8 dakika ya muda mrefu,
na tutaweza kurudi baada ya hii

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na tuangalie hasa
kile kingine yanaweza kwenda vibaya.

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Kama tunaweza dim lights--

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>> [VIDEO avspelning]

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>> -Computers, Tumekuwa wote watakuwa wanakubali
matatizo mara nyingi frustrating kwamba

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kwenda pamoja nao.

102
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Mende, virusi, na programu
glitches ni bei ndogo

103
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kulipa kwa urahisi.

104
00:04:13,230 --> 00:04:17,519
Lakini katika high-tech na yenye kasi
kijeshi na mpango nafasi maombi,

105
00:04:17,519 --> 00:04:22,130
ndogo tatizo Unaweza
litukuzwe katika janga.

106
00:04:22,130 --> 00:04:27,750
Juni 4, 1996, wanasayansi tayari
kuzindua unmanned Ariane 5 roketi.

107
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Ilikuwa ni kufanya kisayansi
satellite iliyoundwa

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00:04:29,890 --> 00:04:33,030
kujua kwa usahihi jinsi
Shamba interacts magnetic Dunia

109
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na upepo wa jua.

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Roketi ilijengwa kwa
Nafasi Shirika la Ulaya

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na lile mbali kutoka kituo yake
katika pwani ya Kifaransa.

112
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>> -Na Sekunde 30 katika
ndege, kwanza

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00:04:44,924 --> 00:04:46,340
niliona kitu kinachoendelea vibaya.

114
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Hiyo nozzles swiveling walikuwa
katika njia ya wao kweli hawapaswi.

115
00:04:49,280 --> 00:04:53,042
Karibu sekunde 40 ndani ya ndege,
wazi gari ilikuwa katika matatizo,

116
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na kwamba wakati walifanya
uamuzi kuiharibu.

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Mbalimbali Usalama Afisa pamoja
guts kubwa taabu kifungo,

118
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akapiga juu ya roketi kabla inaweza
kuwa hatari kwa usalama wa umma.

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>> -Hii Ilikuwa msichana
safari ya Ariane 5,

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na uharibifu wake alichukua
mahali kwa sababu ya kasoro

121
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iliyoingia katika programu roketi.

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-The Tatizo juu ya
Ariane ilikuwa kwamba kuna

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Ilikuwa idadi hiyo inahitajika
64 bits kueleza,

124
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na alitaka kubadilisha
kwa 16 kidogo idadi.

125
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Wao kudhani kuwa idadi
ilikuwa kamwe kwenda kuwa kubwa sana,

126
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kwamba wengi wa wale waliopo tarakimu
64 kidogo idadi walikuwa 0 ya.

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Walikosea.

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>> -The Kutokuwa na uwezo wa moja
programu ya kompyuta kukubali

129
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aina ya idadi yanayotokana na
mwingine ulikuwa ndio mzizi wa kushindwa.

130
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Programu ya maendeleo ambacho kimekuwa
sehemu ya gharama kubwa sana ya teknolojia mpya.

131
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Ariane 4 roketi alikuwa sana
mafanikio, hivyo mengi ya programu

132
00:05:40,760 --> 00:05:43,990
umba kwa sababu ilikuwa pia
kutumika kwenye Ariane 5.

133
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>> Tatizo -The msingi ilikuwa kwamba Ariane
5 mara kwa kasi, kasi kwa kasi zaidi.

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Na programu alikuwa si
waliendelea kwa hilo.

135
00:05:53,000 --> 00:05:56,330
>> -The Uharibifu wa roketi
ilikuwa kubwa kifedha maafa,

136
00:05:56,330 --> 00:05:59,670
wote kutokana na programu dakika makosa.

137
00:05:59,670 --> 00:06:01,990
Lakini hii haikuwa kwanza
wakati data uongofu matatizo

138
00:06:01,990 --> 00:06:05,310
alikuwa wanakumbana kisasa roketi teknolojia.

139
00:06:05,310 --> 00:06:08,300
>> -Katika 1991, na kuanza
Vita ya kwanza ya Ghuba,

140
00:06:08,300 --> 00:06:10,650
Patriot kombora
uzoefu aina hiyo

141
00:06:10,650 --> 00:06:12,650
tatizo idadi kubadilika.

142
00:06:12,650 --> 00:06:15,620
Matokeo yake, watu 28,
Askari 28 wa Marekani

143
00:06:15,620 --> 00:06:18,440
waliuawa na kuhusu
100 wengine kujeruhiwa,

144
00:06:18,440 --> 00:06:21,900
wakati Patriot, ambayo ilitakiwa
kulinda dhidi ya Scuds zinazoingia,

145
00:06:21,900 --> 00:06:24,630
alishindwa kwa moto kombora.

146
00:06:24,630 --> 00:06:29,440
>> -Wakati Iraq walivamia Kuwait na Marekani
ilizindua Jangwa dhoruba katika mapema 1991,

147
00:06:29,440 --> 00:06:33,800
Patriot kombora betri walikuwa uliotumika
kulinda Saudi Arabia na Israeli

148
00:06:33,800 --> 00:06:37,000
kutoka Iraq Scud kombora mashambulizi.

149
00:06:37,000 --> 00:06:40,610
Patriot ni Marekani, kati-mbalimbali
uso-kwa-hewa mfumo

150
00:06:40,610 --> 00:06:43,010
viwandani na kampuni Raytheon.

151
00:06:43,010 --> 00:06:49,080
>> -The Ukubwa wa Patriot interceptor,
yenyewe, ni kuhusu, miguu takribani 20 kwa muda mrefu.

152
00:06:49,080 --> 00:06:51,250
Na ni kizito kuhusu £ 2,000.

153
00:06:51,250 --> 00:06:55,195
Na hubeba warhead ya about--
Nadhani ni takribani paundi 150.

154
00:06:55,195 --> 00:06:59,500
Na warhead, yenyewe,
ni kulipuka juu,

155
00:06:59,500 --> 00:07:02,570
ambayo ina vipande kuzunguka.

156
00:07:02,570 --> 00:07:06,890
Casing ya warhead ni
iliyoundwa na kutenda kama buckshot.

157
00:07:06,890 --> 00:07:09,130
>> Makombora -The ni
kufanyika, 4 kwa chombo,

158
00:07:09,130 --> 00:07:12,080
na ni kusafirishwa kwa Trailer nusu.

159
00:07:12,080 --> 00:07:19,100
>> -The Patriot mfumo wa kupambana na kombora
inakwenda nyuma angalau miaka 20 sasa.

160
00:07:19,100 --> 00:07:22,320
Ni awali ilikuwa iliyoundwa
kama hewa ulinzi kombora

161
00:07:22,320 --> 00:07:24,180
risasi chini ndege ya adui.

162
00:07:24,180 --> 00:07:27,860
Katika Vita ya Kwanza ya Ghuba,
wakati vita kwamba alikuja pamoja,

163
00:07:27,860 --> 00:07:32,745
Jeshi alitaka kuitumia
risasi chini Scuds, si ndege.

164
00:07:32,745 --> 00:07:36,150
Jeshi la Iraq haikuwa
sana ya tatizo,

165
00:07:36,150 --> 00:07:39,110
lakini Jeshi alikuwa na wasiwasi kuhusu Scuds.

166
00:07:39,110 --> 00:07:42,340
Na hivyo walijaribu
kuboresha Patriot.

167
00:07:42,340 --> 00:07:44,760
>> -Intercepting Adui
kombora kusafiri saa tano mach

168
00:07:44,760 --> 00:07:47,250
alikuwa anaenda kuwa changamoto ya kutosha.

169
00:07:47,250 --> 00:07:50,000
Lakini wakati Patriot
alikimbizwa katika huduma,

170
00:07:50,000 --> 00:07:54,030
Jeshi hakuwa na ufahamu wa
Muundo wa Iraq kwamba alifanya

171
00:07:54,030 --> 00:07:56,840
Scuds yao karibu haiwezekani kugonga.

172
00:07:56,840 --> 00:08:01,020
>> -Nini Kilichotokea, ni Scuds kwamba
wanakuja katika, walikuwa imara,

173
00:08:01,020 --> 00:08:02,310
walikuwa tikisika.

174
00:08:02,310 --> 00:08:05,140
Sababu hii,
ilikuwa Iraq, ili

175
00:08:05,140 --> 00:08:09,450
kupata 600 kilomita nje ya
300 kilomita mbalimbali kombora,

176
00:08:09,450 --> 00:08:12,930
alichukua uzito nje ya warhead mbele
na alifanya warhead nyepesi.

177
00:08:12,930 --> 00:08:17,710
Hivyo sasa, Patriot ya kujaribu kuja
katika scud, na zaidi ya muda,

178
00:08:17,710 --> 00:08:21,700
idadi kubwa ya
muda, ingekuwa tu kuruka kwa scud.

179
00:08:21,700 --> 00:08:25,700
>> -Baada Patriot mfumo waendeshaji
barabara Patriot amekosa lengo lake,

180
00:08:25,700 --> 00:08:29,790
wao detonated warhead Patriot wa,
kuepuka majeruhi iwezekanavyo kama

181
00:08:29,790 --> 00:08:32,380
aliruhusiwa kuanguka chini.

182
00:08:32,380 --> 00:08:36,340
>> -yaani Ilikuwa nini watu wengi aliona,
wale fireballs kubwa katika anga,

183
00:08:36,340 --> 00:08:41,289
na kutoeleweka kama
intercepts ya warheads Scud.

184
00:08:41,289 --> 00:08:43,590
Ingawa katika usiku
anga, Patriots alionekana

185
00:08:43,590 --> 00:08:47,020
kuwa mafanikio
kuharibu Scuds, saa Dhahran,

186
00:08:47,020 --> 00:08:49,730
kuna inaweza kuwa hakuna kosa
kuhusu utendaji wake.

187
00:08:49,730 --> 00:08:53,990
Huko, rada Patriot mfumo wa
waliopotea wimbo wa Scud zinazoingia,

188
00:08:53,990 --> 00:08:56,650
na kamwe ilizindua,
kutokana na programu kasoro.

189
00:08:56,650 --> 00:08:59,650

190
00:08:59,650 --> 00:09:04,100
Ilikuwa Israel ambao kwanza aligundua
kwamba tena mfumo ilikuwa juu,

191
00:09:04,100 --> 00:09:07,510
zaidi wakati tofauti
akawa, kutokana na saa iliyoingia

192
00:09:07,510 --> 00:09:09,490
katika mfumo wa kompyuta ya.

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00:09:09,490 --> 00:09:12,670
>> -About Wiki 2 kabla
janga katika Dhahran,

194
00:09:12,670 --> 00:09:15,010
Israel kuripotiwa kwa
Wizara ya Ulinzi,

195
00:09:15,010 --> 00:09:17,940
kwamba mfumo alikuwa kupoteza muda,
kwamba baada ya kuhusu masaa 8 ya kukimbia,

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00:09:17,940 --> 00:09:21,410
waligundua kuwa mfumo ilikuwa
kuwa noticeably chini sahihi.

197
00:09:21,410 --> 00:09:25,290
Wizara ya Ulinzi alijibu kwa
kuwaambia yote ya betri Patriot

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00:09:25,290 --> 00:09:28,070
kwa kuwaacha mifumo
kwa muda mrefu.

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00:09:28,070 --> 00:09:29,960
Wao kamwe alisema nini muda mrefu alikuwa.

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00:09:29,960 --> 00:09:30,460
8 masaa?

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00:09:30,460 --> 00:09:30,960
Masaa 10?

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00:09:30,960 --> 00:09:31,870
Masaa 1000?

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00:09:31,870 --> 00:09:33,734
Hakuna aliyejua.

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00:09:33,734 --> 00:09:35,650
-The Betri Patriot
stationed katika kambi

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00:09:35,650 --> 00:09:40,410
katika Dhahran, na kiujanja yake ya ndani
saa, alikuwa juu zaidi ya saa 100

206
00:09:40,410 --> 00:09:43,041
usiku wa Februari 25.

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00:09:43,041 --> 00:09:47,416
>> -Ni Kupatikana muda wa usahihi
kutokana na 1/10 ya pili.

208
00:09:47,416 --> 00:09:49,290
Sasa 1/10 wa pili ni
idadi ya kuvutia

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00:09:49,290 --> 00:09:52,700
kwa sababu haiwezi kuwa
walionyesha katika binary, hasa.

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00:09:52,700 --> 00:09:54,820
Maana yake, haiwezi
kuwa walionyesha, hasa,

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00:09:54,820 --> 00:09:57,420
katika yoyote kisasa ya digital kompyuta.

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00:09:57,420 --> 00:10:01,460
Ni vigumu kuamini, lakini
kutumia hii kama mfano.

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00:10:01,460 --> 00:10:03,520
Hebu kuchukua idadi, 1/3.

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00:10:03,520 --> 00:10:07,110
1/3 hawezi kuwa walionyesha
katika alisema, hasa.

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00:10:07,110 --> 00:10:11,490
1/3 ni 0.333 kinachoendelea kwa infinity.

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00:10:11,490 --> 00:10:15,486
Hakuna njia ya kufanya hivyo, pamoja na
usahihi kabisa, katika alisema.

217
00:10:15,486 --> 00:10:18,360
Hiyo hasa aina hiyo ya
tatizo kwamba kilichotokea katika Patriot.

218
00:10:18,360 --> 00:10:22,510
Tena mfumo mbio,
mbaya kosa wakati akawa.

219
00:10:22,510 --> 00:10:28,420
>> -Baada Masaa 100 ya operesheni, hitilafu
muda tu kuhusu 1/3 ya pili.

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00:10:28,420 --> 00:10:31,830
Lakini katika suala la kulenga
kombora kusafiri saa mach 5,

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00:10:31,830 --> 00:10:35,890
ni matokeo ya kufuatilia
makosa ya zaidi ya 600 mita.

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00:10:35,890 --> 00:10:38,970
Itakuwa kosa mbaya
kwa askari katika Dhahran.

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00:10:38,970 --> 00:10:45,035
>> -Nini Kilichotokea, ni uzinduzi Scud alikuwa
wanaona na mapema-onyo satelaiti,

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00:10:45,035 --> 00:10:48,930
na wao mpya The kwamba Scud alikuwa
kuja katika mwelekeo wao kwa ujumla.

225
00:10:48,930 --> 00:10:51,170
Hawakujua ambapo alikuwa anakuja.

226
00:10:51,170 --> 00:10:53,990
>> -Ni Mara sasa hadi rada
sehemu ya mfumo wa Patriot,

227
00:10:53,990 --> 00:10:58,520
kutetea Dhahran, kuwapata na kuweka
wimbo wa zinazoingia kombora adui.

228
00:10:58,520 --> 00:10:59,690
>> -The Rada ilikuwa smart sana.

229
00:10:59,690 --> 00:11:01,710
Ingekuwa kweli kufuatilia
nafasi ya Scud

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00:11:01,710 --> 00:11:04,040
na kisha kutabiri ambapo
pengine itakuwa,

231
00:11:04,040 --> 00:11:06,140
wakati mwingine,
rada alimtuma Pulse nje.

232
00:11:06,140 --> 00:11:07,660
Aliyeitwa lango mbalimbali.

233
00:11:07,660 --> 00:11:11,870
>> -Then, Mara moja Patriot
anaamua muda wa kutosha ina

234
00:11:11,870 --> 00:11:16,280
kupita kwenda nyuma na kuangalia ijayo
eneo kwa hii kitu wanaona,

235
00:11:16,280 --> 00:11:17,280
unaendelea nyuma.

236
00:11:17,280 --> 00:11:21,690
Hivyo wakati akarudi vibaya
mahali, basi anaona hakuna kitu

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00:11:21,690 --> 00:11:25,230
na anaamua kwamba kulikuwa hakuna
kitu, ilikuwa kugundua uongo,

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00:11:25,230 --> 00:11:26,650
na matone kufuatilia.

239
00:11:26,650 --> 00:11:29,690
Scud zinazoingia kutoweka
kutoka screen rada,

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00:11:29,690 --> 00:11:32,670
na sekunde baadaye,
slammed ndani ya ngome.

241
00:11:32,670 --> 00:11:38,100
Scud kuuawa 28 na mara ya mwisho
moja fired wakati wa vita vya Ghuba ya kwanza.

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00:11:38,100 --> 00:11:43,460
Kusikitisha, programu updated
aliwasili katika Dhahran siku iliyofuata.

243
00:11:43,460 --> 00:11:46,150
Programu kasoro alikuwa
wamekuwa fasta, kufunga

244
00:11:46,150 --> 00:11:48,940
sura ya kwanza katika wasiwasi
historia ya Patriot kombora.

245
00:11:48,940 --> 00:11:50,220
>> [Mwisho avspelning]

246
00:11:50,220 --> 00:11:54,340
>> DAVID J Malan: Hivyo tutaweza kuchukua kuangalia
baadhi ya mapungufu hayo katika kidogo tu.

247
00:11:54,340 --> 00:11:58,470
Lakini kwanza, hebu
mpito kwa wachache FYI ni.

248
00:11:58,470 --> 00:12:01,575
Hivyo one-- mwishoni mwa wiki hii, kuna
itakuwa sehemu super,

249
00:12:01,575 --> 00:12:04,200
ambayo ni maana ya supplant
sehemu mara kwa mara kufanyika, ambayo

250
00:12:04,200 --> 00:12:05,460
itaanza up wiki hivyo.

251
00:12:05,460 --> 00:12:08,204
Kuangalia tovuti CS50
kwa habari zaidi juu hizo.

252
00:12:08,204 --> 00:12:11,120
Wao pia kuwa zingine na streamed
kuishi kwa wale ambao wanashindwa kuhudhuria.

253
00:12:11,120 --> 00:12:12,980
Tatizo kuweka 1 ni juu ya
tovuti kozi ya tayari,

254
00:12:12,980 --> 00:12:15,105
na tutaweza kuchukua kuangalia
kwamba katika kidogo tu.

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00:12:15,105 --> 00:12:18,350
Na masaa ya ofisi pia, itachukua
mahali hii Jumatatu hadi Alhamisi.

256
00:12:18,350 --> 00:12:20,960
>> Hivyo hii ilikuwa kisheria zaidi
Mpango sisi inaonekana katika wakati wa mwisho.

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00:12:20,960 --> 00:12:23,590
Ni kama rahisi
Mpango unaweza kuandika katika C,

258
00:12:23,590 --> 00:12:25,250
na hata hiyo ni kidogo ya madai ujasiri.

259
00:12:25,250 --> 00:12:25,750
Sawa?

260
00:12:25,750 --> 00:12:28,070
Kwa sababu kuna mengi ya
Wanajidai utata wa jambo hili.

261
00:12:28,070 --> 00:12:30,445
Basi hebu tuangalie kwa haraka katika
nini baadhi ya mambo haya

262
00:12:30,445 --> 00:12:33,080
walikuwa na kisha kujaribu kutoa
mfano wa akili kwa jinsi

263
00:12:33,080 --> 00:12:35,710
hizi rahisi ya mipango
kazi, na kisha tutaweza kuanza

264
00:12:35,710 --> 00:12:38,050
kuangalia mambo magumu milele zaidi.

265
00:12:38,050 --> 00:12:41,280
Hivyo mstari huu hapa, yalionyesha sasa,
katika njano, nini sisi kusema, mara ya mwisho,

266
00:12:41,280 --> 00:12:43,200
kwamba hii haina kwa ajili yetu?

267
00:12:43,200 --> 00:12:45,220
Nini madhumuni ni mtumishi?

268
00:12:45,220 --> 00:12:46,984
Mtu yeyote kutoka mbali nyuma?

269
00:12:46,984 --> 00:12:47,483
Naam.

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00:12:47,483 --> 00:12:48,649
>> Watazamaji MEMBER: [inaudible]

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00:12:48,649 --> 00:12:50,871

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00:12:50,871 --> 00:12:51,704
DAVID J Malan: Mwema.

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00:12:51,704 --> 00:12:53,537
Hivyo ni anatoa huduma
kwa amri, au hebu

274
00:12:53,537 --> 00:12:56,750
kuwaita kazi, kwamba mtu
mwingine aliandika, kwamba ni kutangazwa,

275
00:12:56,750 --> 00:12:58,350
hivyo kusema, katika baadhi ya faili nyingine.

276
00:12:58,350 --> 00:13:02,370
Hivyo tutaweza kuona nini hasa faili h
ni dhidi c file, hatimaye.

277
00:13:02,370 --> 00:13:04,710
Lakini kwa sasa, tu kujua
kwamba printf, kwa mfano,

278
00:13:04,710 --> 00:13:08,370
ni miongoni mwa kazi ambayo yamekuwa
alitangaza katika baadhi ya faili nyingine, mahali fulani

279
00:13:08,370 --> 00:13:12,930
kingine juu ya wingu ngumu kuendesha kwamba
inaruhusu sisi kupata printf na kuitumia

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00:13:12,930 --> 00:13:15,240
bila ya kuwa na kuibuka
kwamba gurudumu wenyewe.

281
00:13:15,240 --> 00:13:16,930
Wakati huo huo, kuu.

282
00:13:16,930 --> 00:13:19,690
Ilikuwa Analog ya kuu, wiki iliyopita ni nini?

283
00:13:19,690 --> 00:13:20,190
Naam.

284
00:13:20,190 --> 00:13:21,460
>> Watazamaji MEMBER: Green bendera ni clicked.

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00:13:21,460 --> 00:13:21,740
>> DAVID J Malan: Yeah.

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00:13:21,740 --> 00:13:23,490
Mwanzo wa, wakati kijani bendera clicked.

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00:13:23,490 --> 00:13:25,560
Ni kama puzzle kipande
kwamba mateke mambo mbali.

288
00:13:25,560 --> 00:13:28,306
Na hivyo vile vile, walivyofanya dunia
aliamua baadhi ya miaka iliyopita kwamba katika C,

289
00:13:28,306 --> 00:13:30,930
na kundi la lugha nyingine,
kama unataka kuandika mpango,

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00:13:30,930 --> 00:13:33,410
kazi yako ya kwanza
ina kuitwa, kuu.

291
00:13:33,410 --> 00:13:34,641
Na ina kuangalia kama hii.

292
00:13:34,641 --> 00:13:36,640
Lakini tutaweza kurudi,
wakati mwingine, kwa nini, int,

293
00:13:36,640 --> 00:13:38,690
na, batili, maana katika mazingira.

294
00:13:38,690 --> 00:13:42,860
Kwa sasa, braces curly ni aina
ya kama puzzle kipande sura Scratch ya

295
00:13:42,860 --> 00:13:45,080
kwamba encapsulates baadhi idadi ya mistari.

296
00:13:45,080 --> 00:13:47,070
Na miongoni mwa juu ya mistari
hapa, ni hii moja hapa.

297
00:13:47,070 --> 00:13:51,610
printf ni kazi ambao lengo katika
maisha ni magazeti kamba mpangilio.

298
00:13:51,610 --> 00:13:55,010
Na kwa mpangilio, I mean wewe
unaweza kuziba katika maadili placeholder,

299
00:13:55,010 --> 00:13:58,360
na unaweza kutaja alisema wangapi
pointi, jinsi wengi idadi ya magazeti

300
00:13:58,360 --> 00:14:00,040
baada ya uhakika decimal na kadhalika.

301
00:14:00,040 --> 00:14:05,040
Na printf, bila shaka, inachukua moja
au hoja au vigezo zaidi,

302
00:14:05,040 --> 00:14:06,770
inayojulikana, zaidi tu, kama pembejeo.

303
00:14:06,770 --> 00:14:09,230
>> Hivyo printf, kama mengi ya
kazi, inachukua pembejeo.

304
00:14:09,230 --> 00:14:12,730
Na pembejeo hizo kuvutiwa
na mabano mbili hapa.

305
00:14:12,730 --> 00:14:15,180
Na ndani ya wale ni pembejeo moja.

306
00:14:15,180 --> 00:14:18,600
Ni kamba, kama tumekuwa kuitwa kuwa,
ambayo ni haki mlolongo wa wahusika,

307
00:14:18,600 --> 00:14:22,310
kama neno, au maneno, au zima
insha hata, katika kati ya quotes mbili.

308
00:14:22,310 --> 00:14:25,712
Na kwamba ni nini kinaendelea kushawishi
tabia ya printf kwa sababu, bila shaka,

309
00:14:25,712 --> 00:14:27,170
ni tu kurefusha maisha magazeti kazi.

310
00:14:27,170 --> 00:14:29,600
Ni si kwenda kujua nini
magazeti, isipokuwa wewe kuwaambia yake.

311
00:14:29,600 --> 00:14:31,000
Na kisha, baadhi minutiae.

312
00:14:31,000 --> 00:14:34,056
Nini sisi kusema hii weird
mlolongo wa ishara ni?

313
00:14:34,056 --> 00:14:34,556
Naam.

314
00:14:34,556 --> 00:14:35,410
>> Watazamaji MEMBER: New line.

315
00:14:35,410 --> 00:14:35,990
>> DAVID J Malan: New line.

316
00:14:35,990 --> 00:14:39,340
Hivyo ni zamu nje, huwezi kugonga,
kuingia, wakati wewe ni kuandika mpango.

317
00:14:39,340 --> 00:14:42,590
Kwa ujumla, compiler ni kwenda kupata
kuchanganyikiwa kidogo kama kwa nini.

318
00:14:42,590 --> 00:14:45,340
Badala yake, una halisi
kusema, nipe mstari mpya hapa.

319
00:14:45,340 --> 00:14:49,506
Na hivyo / n ni nini sisi ujumla
piga tabia kutoroka.

320
00:14:49,506 --> 00:14:50,870
Hivyo n, kwa mstari mpya.

321
00:14:50,870 --> 00:14:53,810
Na mkusanyaji anajua
kwamba wakati anaona / n,

322
00:14:53,810 --> 00:14:57,420
ni lazima kweli kushawishi kompyuta,
hatimaye, au printf, katika kesi hii,

323
00:14:57,420 --> 00:15:00,260
magazeti nje mpya halisi
line, kama kupiga, kuingia,

324
00:15:00,260 --> 00:15:01,480
muhimu kwenye keyboard yako.

325
00:15:01,480 --> 00:15:05,620
Na Mwisho, nini alifanya tunasema
kipande cha syntax ni kwa?

326
00:15:05,620 --> 00:15:06,591
Ni nini kuwakilisha?

327
00:15:06,591 --> 00:15:07,090
Naam.

328
00:15:07,090 --> 00:15:07,490
>> Watazamaji MEMBER: [inaudible]

329
00:15:07,490 --> 00:15:08,660
>> DAVID J Malan: Ni tu
mwisho wa mstari.

330
00:15:08,660 --> 00:15:09,909
Ni mwisho wa taarifa yake.

331
00:15:09,909 --> 00:15:11,890
Na kutambua kwamba hatufanyi
kuziweka kila mahali.

332
00:15:11,890 --> 00:15:13,900
Sisi hakika si kuziweka
katika ncha ya kila mstari.

333
00:15:13,900 --> 00:15:16,680
Kwa mfano, kuna hakuna juu ya
mstari wa kwanza, kuna hakuna kwenye mstari

334
00:15:16,680 --> 00:15:18,680
pamoja, kuu, kuna hakuna
baada ya braces curly,

335
00:15:18,680 --> 00:15:21,740
lakini itabidi kuanza kuona na kupata
ukoo na ambapo ni kuitwa kwa.

336
00:15:21,740 --> 00:15:26,014
Na ni karibu kila mara baada ya kazi
simu au kauli, baadhi ya hatua

337
00:15:26,014 --> 00:15:27,180
kwamba wewe ni kweli kuchukua.

338
00:15:27,180 --> 00:15:29,520
>> Na kujua sasa, hasa kama
miongoni mwa wale chini ya starehe,

339
00:15:29,520 --> 00:15:32,540
hizi ni aina ya mambo ya kijinga
kwamba utasikia kuishia ajali banging

340
00:15:32,540 --> 00:15:33,873
kichwa yako dhidi ya ukuta juu.

341
00:15:33,873 --> 00:15:36,107
Kwa sababu wewe utakuwa na mantiki
ujasiri katika baadhi ya tatizo

342
00:15:36,107 --> 00:15:38,440
umefanya kutatuliwa kwa tatizo
kuweka, na kitu damn tu

343
00:15:38,440 --> 00:15:40,187
si kukusanya au hata kukimbia.

344
00:15:40,187 --> 00:15:43,270
Na hivyo mara nyingi, mapema, ni kwenda
kuwa kwa sababu amekosa mabano,

345
00:15:43,270 --> 00:15:44,455
au amekosa semicolon.

346
00:15:44,455 --> 00:15:46,547
Na hivyo tu kukumbuka
ya aina hii ya mambo,

347
00:15:46,547 --> 00:15:49,380
na jaribu kupata imechanganyikiwa kutokana na
yao kwa sababu kwa haraka sana hana huu

348
00:15:49,380 --> 00:15:50,640
kuwa kofia ya zamani.

349
00:15:50,640 --> 00:15:53,910
Lakini ni rahisi sana kupata
kuchanganyikiwa mapema, matokeo yake.

350
00:15:53,910 --> 00:15:57,020
>> Hivyo sasa, hebu tuangalie jinsi
mstari huu ni kweli kazi

351
00:15:57,020 --> 00:15:59,170
na kisha kuangalia kidogo
ngumu zaidi moja.

352
00:15:59,170 --> 00:16:02,017
Hivyo tuna zaidi ya hapa,
uwezo wa kuchora juu ya screen hii.

353
00:16:02,017 --> 00:16:04,100
Na hebu tuseme kwamba
hii ni kompyuta screen yangu,

354
00:16:04,100 --> 00:16:08,589
lakini mimi kuandika, hodi mpango,
na mimi si kutekelezwa, printf.

355
00:16:08,589 --> 00:16:10,130
Mtu mwingine imetekeleza, printf.

356
00:16:10,130 --> 00:16:12,420
Ambao wangependa wanadai
kutekelezwa, printf?

357
00:16:12,420 --> 00:16:12,920
Kama tunaweza?

358
00:16:12,920 --> 00:16:13,830
Haki wote, nini jina lako?

359
00:16:13,830 --> 00:16:14,155
>> STUDENT 1: [? Copal. ?]

360
00:16:14,155 --> 00:16:15,529
>> DAVID J Malan: Copal, kuja juu juu.

361
00:16:15,529 --> 00:16:16,430
Kuja juu juu.

362
00:16:16,430 --> 00:16:17,070
Wote haki.

363
00:16:17,070 --> 00:16:22,260
Hivyo tuna, hapa, baadhi ya vitambulisho jina,
tangu tutaweza kufanya mchezo kidogo ya hii.

364
00:16:22,260 --> 00:16:26,270
Na sisi nitakuita, printf.

365
00:16:26,270 --> 00:16:30,170
Na kama unataka kuja hapa,
nini nimekuwa inayotolewa tu kwenye screen,

366
00:16:30,170 --> 00:16:32,340
ni rahisi kabisa, kuna Kwangu mimi, hii.

367
00:16:32,340 --> 00:16:35,550
>> Haki wote, hivyo, hello jina langu ni,
printf, kama Ningependa kuweka kwamba katika.

368
00:16:35,550 --> 00:16:35,740
Wote haki.

369
00:16:35,740 --> 00:16:37,360
Na kama unaweza kwenda kusimama
na screen ya kompyuta

370
00:16:37,360 --> 00:16:39,730
kana kwamba ni kazi ambayo
alikuja na mfumo huu wa kompyuta.

371
00:16:39,730 --> 00:16:42,063
Na madhumuni yako katika maisha ni
kwa kweli magazeti kitu.

372
00:16:42,063 --> 00:16:44,560
Lakini kiasi kama mpango sisi
tu alikuwa kwenye screen, hapa,

373
00:16:44,560 --> 00:16:47,060
tunakwenda kuwa na
kweli kukupa baadhi ya pembejeo.

374
00:16:47,060 --> 00:16:51,810
>> Na hivyo, kama pembejeo yangu, hapa, ni
inaonekana, nini ni kupita kwa printf,

375
00:16:51,810 --> 00:16:53,730
hebu aina ya maskhara it up kama hii.

376
00:16:53,730 --> 00:16:58,720
Mimi nina kwenda literally kuandika kwenye
kipande cha karatasi, "hello, dunia,"

377
00:16:58,720 --> 00:17:03,020
backslash N. Na kwa kuwa wazi, nini
Nimekuwa inayotolewa tu juu ya kipande cha karatasi,

378
00:17:03,020 --> 00:17:04,020
inaonekana kama hii.

379
00:17:04,020 --> 00:17:08,730
Hivyo wakati mimi kuendesha mpango huu, na hii
njano mstari wa kanuni anapata kunyongwa,

380
00:17:08,730 --> 00:17:12,970
ni kana kwamba, mpango hello,
ni kuwapatia baadhi ya pembejeo mbali na kazi

381
00:17:12,970 --> 00:17:13,970
kwamba mtu mwingine aliandika.

382
00:17:13,970 --> 00:17:16,595
>> Na kama wewe, kidole,
naweza kweli, kidole,

383
00:17:16,595 --> 00:17:21,520
kuteka juu ya screen chochote
ni wewe wamekuwa mitupu,

384
00:17:21,520 --> 00:17:27,465
athari, hatimaye, ni kwa
kuona hasa kwamba, kwenye screen.

385
00:17:27,465 --> 00:17:29,140
Na kidogo kona kesi hapa.

386
00:17:29,140 --> 00:17:31,540
Na nzuri, sisi asipate
, mstari wa mwezi, katika hatua hii.

387
00:17:31,540 --> 00:17:33,900
Itakuwa sahihi kwa wewe
kupanga kuteka newline.

388
00:17:33,900 --> 00:17:36,810
Lakini kama sisi kuendelea kuandika maneno kwenye
screen, wangeweza kuishia chini hiyo.

389
00:17:36,810 --> 00:17:39,560
>> Hivyo asante sana, lakini fimbo
karibu hapa kwa muda mmoja tu.

390
00:17:39,560 --> 00:17:42,860
Kwa sasa tunataka mtu mwingine
kujitolea, kama tunaweza,

391
00:17:42,860 --> 00:17:46,830
hiyo ni kwenda haja ya kuwa na jukumu
of-- Ni watu tu katika orchestra

392
00:17:46,830 --> 00:17:47,355
hivi sasa.

393
00:17:47,355 --> 00:17:47,980
Jinsi about-- sawa.

394
00:17:47,980 --> 00:17:48,480
Hapa hapa.

395
00:17:48,480 --> 00:17:49,180
Kuja juu juu.

396
00:17:49,180 --> 00:17:49,955
Nini jina lako?

397
00:17:49,955 --> 00:17:50,922
>> STUDENT 2: [? Ivay. ?]

398
00:17:50,922 --> 00:17:51,796
DAVID J Malan: Samahani?

399
00:17:51,796 --> 00:17:52,990
STUDENT 2: [? Ivay. ?]

400
00:17:52,990 --> 00:17:55,320
DAVID J Malan: Ethani, kuja juu juu.

401
00:17:55,320 --> 00:17:55,820
Hakuna?

402
00:17:55,820 --> 00:17:58,390
Je, mimi kupata vibaya kwamba, hata
baada ya wewe alisema ni mara mbili?

403
00:17:58,390 --> 00:17:58,890
Kuja juu juu.

404
00:17:58,890 --> 00:18:00,030
Ni vigumu kusikia hapa.

405
00:18:00,030 --> 00:18:05,240

406
00:18:05,240 --> 00:18:05,740
Sawa.

407
00:18:05,740 --> 00:18:07,190
Na mimi nina sorry, nini jina lako?

408
00:18:07,190 --> 00:18:07,680
>> STUDENT 2: [? Ivay. ?]

409
00:18:07,680 --> 00:18:08,790
>> [? DAVID J Malan: Ivay. ?] Sawa.

410
00:18:08,790 --> 00:18:10,430
Kwa sasa, kama huna
akili, wewe ni GetString.

411
00:18:10,430 --> 00:18:11,013
>> STUDENT 2: Sawa.

412
00:18:11,013 --> 00:18:11,797
Baridi.

413
00:18:11,797 --> 00:18:14,630
DAVID J Malan: Hivyo kama ungependa
kusimama hapa kwa muda tu,

414
00:18:14,630 --> 00:18:17,100
hebu tuangalie kidogo
zaidi tata mpango, kwamba

415
00:18:17,100 --> 00:18:18,670
sasa ina mistari mitatu ya kificho.

416
00:18:18,670 --> 00:18:24,080
Hivyo tuna, moja, hali jina lako kwa kutumia
printf; mbili, wito kwa GetString,

417
00:18:24,080 --> 00:18:28,060
ikifuatiwa na zoezi kwa
kutofautiana kuitwa, kamba s, au kuitwa s;

418
00:18:28,060 --> 00:18:31,260
na kisha mwingine wito kwa, printf,
lakini wakati huu na pembejeo mbili.

419
00:18:31,260 --> 00:18:33,646
>> Hivyo tumekuwa tayari amefanya hali
jina lako, au tuseme, tumekuwa

420
00:18:33,646 --> 00:18:34,770
tayari amefanya printf simu.

421
00:18:34,770 --> 00:18:38,960
Hivyo nina kwenda kuandika, majina zako.

422
00:18:38,960 --> 00:18:42,089
Na hivyo, nini mimi kwenda kwa
kupita, printf, katika muda tu,

423
00:18:42,089 --> 00:18:43,005
ni rahisi kabisa, huu.

424
00:18:43,005 --> 00:18:47,760
Hivyo kama unataka kwenda mbele na kuteka hii
juu ya screen, hiyo ni mchango wako sasa.

425
00:18:47,760 --> 00:18:48,260
Wote haki.

426
00:18:48,260 --> 00:18:51,160
Na kusahau kamba, sasa tuna
line yetu wenyewe ya kificho hapa.

427
00:18:51,160 --> 00:18:54,470
Hivyo katika, GetString, tunahitaji
kwa kweli kuwaita, GetString.

428
00:18:54,470 --> 00:18:57,920
Hivyo madhumuni yako katika maisha ni kutembea tu
nje katika orchestra, kama unaweza,

429
00:18:57,920 --> 00:18:58,980
na kupata jina la mtu.

430
00:18:58,980 --> 00:19:00,860
Lakini hebu kukupa
kitu cha kuweka kwenye.

431
00:19:00,860 --> 00:19:02,908
Kama unataka, go
mbele na kupata kamba,

432
00:19:02,908 --> 00:19:05,241
kupata jina la mtu juu ya kwamba
kipande cha karatasi, kama unaweza.

433
00:19:05,241 --> 00:19:12,940

434
00:19:12,940 --> 00:19:13,530
>> Wote haki.

435
00:19:13,530 --> 00:19:15,250
Na tutaweza kuona, katika muda tu,
jina lake sisi ni kupata.

436
00:19:15,250 --> 00:19:17,630
Wakati huo huo, kile nitakacho
kuwa tayari, ni tupu kipande

437
00:19:17,630 --> 00:19:21,340
cha karatasi, ambayo, mimi nina kwenda
kuhifadhi chochote thamani yake

438
00:19:21,340 --> 00:19:25,752
ni kwamba GetString ni kurudi kwangu,
Mimi, kuwa kamba kutofautiana kuitwa, s.

439
00:19:25,752 --> 00:19:26,252
Wote haki.

440
00:19:26,252 --> 00:19:27,293
Basi je, wewe hapa?

441
00:19:27,293 --> 00:19:27,950
Nik.

442
00:19:27,950 --> 00:19:28,450
Wote haki.

443
00:19:28,450 --> 00:19:30,910
Hivyo tuna jina Nik hapa.

444
00:19:30,910 --> 00:19:33,750
Hivyo hii ni nini literally
imekuwa akarudi

445
00:19:33,750 --> 00:19:35,810
kwangu, ili kuzungumza, na GetString.

446
00:19:35,810 --> 00:19:38,720
>> Mimi, sasa, naenda
kutekeleza upande wa kushoto mkono

447
00:19:38,720 --> 00:19:43,440
ya kwamba kujieleza, ambapo mimi tu
nakala chini, kwa madhumuni ya leo, Nik.

448
00:19:43,440 --> 00:19:46,470
Hivyo sasa, nina kutofautiana
kuitwa, s, kuhifadhi jina Nik ya.

449
00:19:46,470 --> 00:19:49,520
Nimekuwa tayari kukabidhiwa kwa
printf, hoja uliopita.

450
00:19:49,520 --> 00:19:52,800
Lakini katika mstari wetu tatu na ya mwisho ya
kanuni, mimi kwa kweli kuwa na mkono printf

451
00:19:52,800 --> 00:19:58,500
kitu kidogo different--
"hello,% s," backslash n.

452
00:19:58,500 --> 00:20:01,510
>> Na hivyo mstari wa mwisho mimi nina kwenda
kwa send-- jambo la mwisho mimi nina

453
00:20:01,510 --> 00:20:03,060
kwenda kuandika sasa, ni hii.

454
00:20:03,060 --> 00:20:06,310
Hivyo mistari miwili ya kificho, au
badala mstari wa mwisho wa kanuni,

455
00:20:06,310 --> 00:20:10,690
wito kwa ajili ya mbili inputs--
moja, hii, na wawili, huu.

456
00:20:10,690 --> 00:20:13,330
Hivyo kama printf yetu kufanya kazi
sasa wanaweza kuchukua hizi kama pembejeo,

457
00:20:13,330 --> 00:20:16,000
napenda wazi screen kwa ajili yenu.

458
00:20:16,000 --> 00:20:17,250
Kwa kweli hakuna, unaweza kwenda mbele.

459
00:20:17,250 --> 00:20:19,333
Tutaweza kuondoka it up, tangu
ni juu ya mpango huo.

460
00:20:19,333 --> 00:20:21,760

461
00:20:21,760 --> 00:20:27,380
Tunapaswa kuona, hello, Nik.

462
00:20:27,380 --> 00:20:27,880
Wote haki.

463
00:20:27,880 --> 00:20:29,670
Hivyo hii ilikuwa chache kabisa
hoops kuruka kupitia, tu

464
00:20:29,670 --> 00:20:31,620
kuandika, hali yako
jina, na, hello, Nik.

465
00:20:31,620 --> 00:20:37,210
Lakini wazo hili rahisi la ujumbe kupita,
ya pembejeo kupita na pato kupokea,

466
00:20:37,210 --> 00:20:40,430
ni hasa mfano tunakwenda na
kwa maana hata kazi ngumu zaidi.

467
00:20:40,430 --> 00:20:41,804
Hivyo asante sana kwa ninyi wawili.

468
00:20:41,804 --> 00:20:43,730
Tuna matatizo nzuri
mpira hapa kwa ajili yenu.

469
00:20:43,730 --> 00:20:48,890
Na kuwashukuru kwa GetString yetu
na kujitolea printf sawa.

470
00:20:48,890 --> 00:20:49,551
Asante.

471
00:20:49,551 --> 00:20:50,050
Wote haki.

472
00:20:50,050 --> 00:20:50,966
Asante kwa ninyi wawili.

473
00:20:50,966 --> 00:20:56,640

474
00:20:56,640 --> 00:21:00,430
>> Hivyo tumekuwa kuzungumza juu ya
hivi sasa, wengi wao wakiwa kuhusu masharti.

475
00:21:00,430 --> 00:21:06,550
Na zinageuka kuwa C wanaweza kweli
kuelewa aina kadhaa tofauti data.

476
00:21:06,550 --> 00:21:08,860
Kwa kweli, hebu kuchukua
a tuangalie hizi hapa.

477
00:21:08,860 --> 00:21:12,490
Hivyo C, na mengi ya lugha,
kuelewa mambo kuitwa chars.

478
00:21:12,490 --> 00:21:16,852
Char ujumla
Byte moja tu, au bits nane.

479
00:21:16,852 --> 00:21:19,810
Na inawakilisha tabia moja,
kama barua A, au mji mkuu

480
00:21:19,810 --> 00:21:21,990
barua A, au barua lowercase
, Au mshangao uhakika,

481
00:21:21,990 --> 00:21:25,440
au tabia yoyote kwamba unaweza aina katika
keyboard yako, na wakati mwingine hata zaidi.

482
00:21:25,440 --> 00:21:26,795
Sisi pia kutokea kwa kuona ikifungwa.

483
00:21:26,795 --> 00:21:31,160
Kuelea ni, kwa ujumla,
32-bit thamani, au ka nne

484
00:21:31,160 --> 00:21:33,660
kwa sababu tena, byte moja ni bits nane.

485
00:21:33,660 --> 00:21:36,675
>> Hivyo kuelea ni floating kumweka thamani,
kitu kwa uhakika decimal.

486
00:21:36,675 --> 00:21:38,550
Na hakika, hilo ndilo
movie alikuwa akizungumza

487
00:21:38,550 --> 00:21:42,240
kuhusu wakati wao alizungumza kuhusu yaliyo
maadili uhakika, baadhi idadi maalum ya bits

488
00:21:42,240 --> 00:21:43,940
inatumiwa kuwakilisha idadi halisi.

489
00:21:43,940 --> 00:21:45,740
Lakini pia kuna mambo kuitwa mara mbili.

490
00:21:45,740 --> 00:21:47,860
Hizi zipo katika Java,
kama wameweza kuchukuliwa APCS,

491
00:21:47,860 --> 00:21:51,540
na mara mbili, kama jina nashiriki
unaonyesha, ni mara mbili kubwa kama kuelea.

492
00:21:51,540 --> 00:21:54,540
Bado idadi halisi,
ni tu ana vipande zaidi

493
00:21:54,540 --> 00:21:58,390
na ambayo kwa kuwa milele sahihi zaidi,
au kuhifadhi idadi hata kubwa.

494
00:21:58,390 --> 00:21:58,890
int ni rahisi.

495
00:21:58,890 --> 00:22:00,181
Kuongelea huo jana.

496
00:22:00,181 --> 00:22:01,160
Ni tu integer.

497
00:22:01,160 --> 00:22:03,980
Na ni kwa ujumla 32
bits, au ka nne.

498
00:22:03,980 --> 00:22:07,850
>> Na hivyo, kama una, hebu angalia sasa,
32 bits-- na sisi alifanya hivyo katika wiki 0,

499
00:22:07,850 --> 00:22:10,820
milele hivyo briefly-- kama una
32 bits, nini kubwa

500
00:22:10,820 --> 00:22:13,580
Idadi unaweza kuwakilisha kama integer?

501
00:22:13,580 --> 00:22:16,080
Kutoa au kuchukua?

502
00:22:16,080 --> 00:22:18,380
Ni kama bilioni 4,
na kwamba tu kama tuko

503
00:22:18,380 --> 00:22:20,690
anayewakilisha idadi chanya tu.

504
00:22:20,690 --> 00:22:23,930
Kama una bits 32, na unataka
kuwakilisha idadi hasi pia,

505
00:22:23,930 --> 00:22:27,100
mbalimbali wako ni, kimsingi, hasi
Bilioni 2 kwa chanya bilioni 2.

506
00:22:27,100 --> 00:22:29,250
Lakini kwa ujumla, tutaweza kuanza
saa 0 kwenda hadi bilioni 4.

507
00:22:29,250 --> 00:22:32,400
>> Huna kujua just, lakini
tunaweza kuona hii, kwa kweli, kama mimi tu

508
00:22:32,400 --> 00:22:36,400
kufungua calculator kidogo, hapa.

509
00:22:36,400 --> 00:22:41,070
Siwezi kufanya 2 32, na
hiyo ni hasa jinsi kubwa,

510
00:22:41,070 --> 00:22:43,190
jinsi wengi unaweza maadili
kuwakilisha, kwa 32 bits.

511
00:22:43,190 --> 00:22:44,442
Na ni takribani bilioni 4.

512
00:22:44,442 --> 00:22:46,900
Hivyo tutaweza kushika kuona idadi hiyo
katika maeneo kadhaa tofauti.

513
00:22:46,900 --> 00:22:48,890
Lakini kama unahitaji tena
nambari ya hapo,

514
00:22:48,890 --> 00:22:51,670
zinageuka kuna ya
kitu kinachoitwa kwa muda mrefu kwa muda mrefu.

515
00:22:51,670 --> 00:22:54,005
Na kwa muda mrefu kwa muda mrefu ni
ujumla 64 bits, ambayo

516
00:22:54,005 --> 00:22:56,380
ina maana ni amri ya kiwango
hata kubwa kuliko int.

517
00:22:56,380 --> 00:22:59,510
>> Hivyo siwezi hata kutamka kubwa
idadi hiyo unaweza kuwakilisha,

518
00:22:59,510 --> 00:23:01,340
lakini ni kikubwa kubwa.

519
00:23:01,340 --> 00:23:05,190
Sasa kama kando, kihistoria,
kama int ni 32 bits,

520
00:23:05,190 --> 00:23:12,780
na kwa muda mrefu kwa muda mrefu ni 64 bits, jinsi
kubwa ni kwa muda mrefu, si muda mrefu kwa muda mrefu?

521
00:23:12,780 --> 00:23:16,500

522
00:23:16,500 --> 00:23:20,330
Wewe d nadhani ni muda mrefu zaidi int
lakini labda chini ya muda mrefu kuliko muda mrefu,

523
00:23:20,330 --> 00:23:21,400
lakini ni kweli inategemea.

524
00:23:21,400 --> 00:23:23,400
>> Na hivyo ni zamu nje moja
Matatizo ya pia,

525
00:23:23,400 --> 00:23:26,830
na kuandika kanuni juu ya mifumo fulani,
ni kwamba si wote wa aina hizi data

526
00:23:26,830 --> 00:23:28,440
na kabla ya kuamua maadili.

527
00:23:28,440 --> 00:23:29,771
Wakati mwingine ni bits hii wengi.

528
00:23:29,771 --> 00:23:31,020
Wakati mwingine ni kwamba bits wengi.

529
00:23:31,020 --> 00:23:32,750
Hivyo kweli kuwa kujua,
wakati mwingine, nini vifaa

530
00:23:32,750 --> 00:23:34,083
wewe ni mbio programu yako kwenye.

531
00:23:34,083 --> 00:23:36,960
Shukrani nyingi, lugha nyingine na
aina nyingine takwimu ambazo sasa zipo,

532
00:23:36,960 --> 00:23:38,400
kuruhusu kuwa sahihi zaidi.

533
00:23:38,400 --> 00:23:41,220
Naam, tuliona kamba,
na tuliona bool, pia,

534
00:23:41,220 --> 00:23:43,960
lakini zinageuka wale kuja
tu kwa maktaba CS50.

535
00:23:43,960 --> 00:23:46,240
Hivyo wale si kujengwa
ndani ya C. Wale badala yake,

536
00:23:46,240 --> 00:23:49,340
kuja katika kuwa faili inayoitwa
CS50.h, kwamba tutaweza hatimaye

537
00:23:49,340 --> 00:23:51,831
peel nyuma tabaka la.

538
00:23:51,831 --> 00:23:53,830
Lakini kwa sasa, wao ni tu
ziada data aina.

539
00:23:53,830 --> 00:23:57,060
Bool ni kweli au uongo, na a
kamba ni mlolongo wa wahusika,

540
00:23:57,060 --> 00:23:57,970
kama neno.

541
00:23:57,970 --> 00:24:01,690
Sasa printf, tumeona, ina
placeholders,% s ni moja.

542
00:24:01,690 --> 00:24:05,430
Na unaweza kuwa na uwezo, kwa sasa,
kudai kutokana na mifano hiyo mengine, jinsi

543
00:24:05,430 --> 00:24:07,720
unaweza kuwa na placeholder
kwa aina tofauti ya data.

544
00:24:07,720 --> 00:24:11,150
Kwa mfano, kuchukua nadhani, kama wewe
alitaka magazeti nje Char moja kutumia

545
00:24:11,150 --> 00:24:15,270
printf, placeholder pengine% c.

546
00:24:15,270 --> 00:24:19,650
Na kama unataka magazeti nje
integer na placeholder,% i.

547
00:24:19,650 --> 00:24:25,150
% lld ni muda mrefu thamani alisema,
lakini kwa muda mrefu kwa muda mrefu, hivyo kwamba ramani na ile.

548
00:24:25,150 --> 00:24:28,640
Na% kisha f kwa yaliyo
hatua thamani au kwa mara mbili,

549
00:24:28,640 --> 00:24:31,270
hivyo wakati mwingine wao ni re-kutumika
katika mazingira tofauti.

550
00:24:31,270 --> 00:24:33,350
Hivyo tutaweza kuona na kutumia
Baadhi ya watu baada ya muda.

551
00:24:33,350 --> 00:24:36,420
Na printf na kazi nyingine pia
msaada wa wengine kutoroka Utaratibu,

552
00:24:36,420 --> 00:24:38,080
na wakati mwingine, hizi ni muhimu.

553
00:24:38,080 --> 00:24:39,770
Hivyo backslash n ni mstari mpya.

554
00:24:39,770 --> 00:24:42,886
Backslash t, je mtu yeyote
wanataka kuchukua kumchoma?

555
00:24:42,886 --> 00:24:43,760
Watazamaji MEMBER: Tab.

556
00:24:43,760 --> 00:24:44,551
DAVID J Malan: Tab.

557
00:24:44,551 --> 00:24:46,810
Hivyo kama kweli wanataka
magazeti nje tabo, si

558
00:24:46,810 --> 00:24:49,940
idadi maalum ya maeneo ya halisi lakini
tab tabia, huna hit yako,

559
00:24:49,940 --> 00:24:53,490
tab, muhimu kwenye keyboard, kwa ujumla,
wewe kweli kufanya backslash t.

560
00:24:53,490 --> 00:24:57,750
Backslash mbili kunukuu,
kwa nini mimi milele wanataka hivyo?

561
00:24:57,750 --> 00:24:58,250
Sawa?

562
00:24:58,250 --> 00:25:00,417
Kwa nini siwezi tu aina
mara mbili kunukuu kwenye keyboard yangu?

563
00:25:00,417 --> 00:25:02,124
Watazamaji MEMBER:
Kwa sababu, vinginevyo, ni

564
00:25:02,124 --> 00:25:04,830
kwenda nadhani ni mwisho
ya kama magazeti yako [? maandishi. ?]

565
00:25:04,830 --> 00:25:05,420
>> DAVID J Malan: Hasa.

566
00:25:05,420 --> 00:25:07,211
Kumbuka, na yetu
mifano printf, wakati sisi

567
00:25:07,211 --> 00:25:10,075
walikuwa kupita kwa printf katika pembejeo,
upande wa kushoto wa kamba kwamba pembejeo

568
00:25:10,075 --> 00:25:12,950
na juu ya haki ya pembejeo kwamba
spring, bila shaka, alikuwa kunukuu mara mbili.

569
00:25:12,950 --> 00:25:16,270
Kama mchango wako mwenyewe ana mara mbili
kunukuu katikati ya kwamba,

570
00:25:16,270 --> 00:25:18,920
kompyuta nguvu uwezekano
kupata kuchanganyikiwa, kama kwa,

571
00:25:18,920 --> 00:25:20,760
anafanya kunukuu hii mara mbili
mali katikati?

572
00:25:20,760 --> 00:25:22,150
Je, ni mali na mmoja wa kushoto?

573
00:25:22,150 --> 00:25:23,566
Je, ni mali na haki ya mmoja?

574
00:25:23,566 --> 00:25:26,780
Na hivyo, kama unataka kufanya hivyo super
wazi, huna backslash mbili kunukuu,

575
00:25:26,780 --> 00:25:30,480
hivyo kwamba ni alitoroka, ili kuzungumza, na
siyo alikataa kwa kitu kingine.

576
00:25:30,480 --> 00:25:34,400
Na kuna wengine wachache hapa,
backslash r, quotes moja, 0,

577
00:25:34,400 --> 00:25:36,510
ili tuone baada ya muda, kama vile.

578
00:25:36,510 --> 00:25:37,760
Na sasa, vipi kuhusu kazi?

579
00:25:37,760 --> 00:25:41,630
>> Hivyo hatua ambazo tunaweza kuchukua hivi sasa
katika lugha hii, C, vizuri, tumeona,

580
00:25:41,630 --> 00:25:44,320
printf, bila shaka, na wote
wengine juu ya screen,

581
00:25:44,320 --> 00:25:47,140
hapa, kwamba tutaweza kutumia kwa
kwanza wiki chache tu kozi,

582
00:25:47,140 --> 00:25:48,485
kuja wakati maktaba CS50.

583
00:25:48,485 --> 00:25:51,850
Nao kufanya ni rahisi sana, katika
C, kwa kweli kupata pembejeo mtumiaji.

584
00:25:51,850 --> 00:25:54,200
Ni zinageuka kuwa katika C, na
kusema ukweli katika lugha kadhaa,

585
00:25:54,200 --> 00:25:57,450
ni maumivu ya kweli katika shingo kufanya
kitu rahisi, kama haraka mtumiaji

586
00:25:57,450 --> 00:26:01,310
kwa keyboard, kwa pembejeo yake.

587
00:26:01,310 --> 00:26:03,240
Na hivyo kazi hizi iwe rahisi.

588
00:26:03,240 --> 00:26:05,472
>> Na pia ina makosa
kuangalia kote,

589
00:26:05,472 --> 00:26:07,180
hivyo kwamba, wakati
kukumbuka siku ya Jumatano, sisi

590
00:26:07,180 --> 00:26:09,740
nikaona, jaribu tena, onyo,
wakati sikuweza kushirikiana,

591
00:26:09,740 --> 00:26:11,700
na mimi niliandika neno, badala ya namba?

592
00:26:11,700 --> 00:26:15,402
Tumefanya kuondoa nzito mapema
juu ya kuhakikisha user inashirikiana.

593
00:26:15,402 --> 00:26:17,860
Lakini haya ni mafunzo tu
magurudumu kwamba sisi hatimaye,

594
00:26:17,860 --> 00:26:19,640
na kwa haraka, kuchukua mbali.

595
00:26:19,640 --> 00:26:22,630
>> Hivyo kwa kurejea, basi,
hebu tuangalie kwa haraka,

596
00:26:22,630 --> 00:26:26,620
kiasi kama tulivyofanya kwa Scratch, katika
baadhi constructs kisheria katika C.

597
00:26:26,620 --> 00:26:28,580
Hii ni maana ya, aina
ya, kuwa ziara ya kimbunga,

598
00:26:28,580 --> 00:26:30,990
hivyo tu kwamba una kumbukumbu
na kwamba wameweza kuona mambo kwa mara ya kwanza.

599
00:26:30,990 --> 00:26:34,100
Lakini basi tutaangalia coding halisi
kutumia baadhi ya vipengele hivi.

600
00:26:34,100 --> 00:26:36,710
Sana kama katika Scratch,
wakati tulikuwa kauli kama,

601
00:26:36,710 --> 00:26:41,570
kusema au, ngoja, katika C, hatuwezi kuwa na
kazi pamoja, kama printf.

602
00:26:41,570 --> 00:26:45,350
>> Kama tunataka kueleza hali
katika C, ni sawa, katika roho,

603
00:26:45,350 --> 00:26:47,840
kwa kuwa puzzle kipande kwamba
inaonekana kama hii katika Scratch.

604
00:26:47,840 --> 00:26:49,850
Lakini badala yake, sisi
literally tu kuandika, ikiwa.

605
00:26:49,850 --> 00:26:51,830
Na kisha, katika mabano,
sisi kuweka hali,

606
00:26:51,830 --> 00:26:54,807
ambapo hali hiyo ndiyo tutaweza
piga, tena, kujieleza bulin.

607
00:26:54,807 --> 00:26:56,390
Na tena, hii ni aina ya pseudocode.

608
00:26:56,390 --> 00:26:58,830
Na, kwa kweli, // ni maoni.

609
00:26:58,830 --> 00:27:00,550
Ni maneno tu Kiingereza kwa mwenyewe.

610
00:27:00,550 --> 00:27:03,000
Lakini hii ni kwa ujumla
muundo wa, kama, hali hiyo.

611
00:27:03,000 --> 00:27:05,220
Lakini tutaweza kuona halisi
mifano katika muda tu.

612
00:27:05,220 --> 00:27:07,960
>> Kama unataka kuwa na
njia mbili uma katika barabara,

613
00:27:07,960 --> 00:27:11,740
kiasi kama tulivyofanya kwa kujitolea yetu juu ya
Jumatano, unaweza kuwa, mwingine kama.

614
00:27:11,740 --> 00:27:16,020
Na kama unataka kuwa na tatu na
hali ya mwisho, au hali ya msingi,

615
00:27:16,020 --> 00:27:19,006
unaweza kuwa tu mwingine kuzuia, huko.

616
00:27:19,006 --> 00:27:21,880
Na vile vile, kwa maneno ya bulin,
unaweza, na, pamoja.

617
00:27:21,880 --> 00:27:24,296
Na tuliona juu ya Jumatano, kwamba
siyo ampersand moja,

618
00:27:24,296 --> 00:27:28,220
ni mbili, kwa sababu ngazi ya chini kuwa
tutaweza hatimaye kuona na kucheza na.

619
00:27:28,220 --> 00:27:30,410
Au-ing mambo pamoja
ni 2 wima baa.

620
00:27:30,410 --> 00:27:32,240
On Marekani keyboard, hii
kwa ujumla ni muhimu

621
00:27:32,240 --> 00:27:35,730
kwa Shift muhimu juu
Kuingia yako muhimu au Rudisha muhimu.

622
00:27:35,730 --> 00:27:38,620
>> Kisha kuna vitu hivi kwamba
tutaweza kutumia labda mara moja au mbili.

623
00:27:38,620 --> 00:27:42,570
Wao ni functionally sawa na
nini unaweza kufanya na, kama, mwingine kama,

624
00:27:42,570 --> 00:27:44,950
kingine kama mwingine, kujenga,
lakini wao ni kuitwa kubadili.

625
00:27:44,950 --> 00:27:48,020
Wao kuangalia tofauti sana, lakini tutaweza
ona katika baadhi ya usambazaji kanuni zetu,

626
00:27:48,020 --> 00:27:51,890
kwa ajili ya baadaye kuweka tatizo, uwezekano mkubwa,
kuwa ni wakati mwingine tu prettier

627
00:27:51,890 --> 00:27:54,060
njia ya kuonyesha nzima
rundo la masharti,

628
00:27:54,060 --> 00:27:57,590
bila ya kuwa mengi ya braces curly na
mengi ya mabano na indentation.

629
00:27:57,590 --> 00:28:01,910
Lakini wao kutupatia tena
nguvu kuliko sisi tayari.

630
00:28:01,910 --> 00:28:02,550
Na sasa loops.

631
00:28:02,550 --> 00:28:05,020
Na hii moja, tutaangalia
katika kidogo polepole zaidi.

632
00:28:05,020 --> 00:28:08,470
Lakini basi, tutaweza kuanza kutumia hizi,
hasa kwa wale ambao tayari ukoo.

633
00:28:08,470 --> 00:28:13,830
Hii ni njia kisheria, ikiwa incredibly
arcane njia, kuandika kitanzi katika C.

634
00:28:13,830 --> 00:28:15,896
>> Sasa kitanzi katika Scratch ilikuwa
pretty moja kwa moja.

635
00:28:15,896 --> 00:28:17,020
Una, milele, kuzuia.

636
00:28:17,020 --> 00:28:19,760
Una, kurudia, kuzuia na
idadi tu una aina katika.

637
00:28:19,760 --> 00:28:22,220
Na kwa, kwa kitanzi, unaweza
kutekeleza wote wawili wa mawazo hayo,

638
00:28:22,220 --> 00:28:23,595
lakini ni kidogo zaidi ya kiufundi.

639
00:28:23,595 --> 00:28:25,994
Lakini kusema ukweli, pia ni
rahisi.

640
00:28:25,994 --> 00:28:28,160
Mara unajua utaratibu wa
shughuli, wewe literally

641
00:28:28,160 --> 00:28:30,910
ni kwenda tu kuziba katika maadili
na kuwaambia kompyuta nini cha kufanya.

642
00:28:30,910 --> 00:28:32,800
Hivyo hapa ni mfano.

643
00:28:32,800 --> 00:28:38,040
Hii ni kitanzi kwamba, kabisa
tu, makosa kutoka namba moja hadi

644
00:28:38,040 --> 00:28:40,187
kupitia mwingine.

645
00:28:40,187 --> 00:28:42,020
Na tu na glancing
saa hiyo, hata kama una

646
00:28:42,020 --> 00:28:44,660
hawana uzoefu kabla na
lugha hii, nini idadi

647
00:28:44,660 --> 00:28:46,920
je, ni pengine kuanza kuhesabu katika?

648
00:28:46,920 --> 00:28:47,730
OK, 0.

649
00:28:47,730 --> 00:28:50,240
Na mimi nina guessing hiyo ni kwa sababu wewe
kuona kwamba kuna int na i,

650
00:28:50,240 --> 00:28:51,073
ambayo ni kutofautiana.

651
00:28:51,073 --> 00:28:52,390
Ni initialized kwa 0.

652
00:28:52,390 --> 00:28:55,670
>> Na kisha baadaye, inaonekana kama
sisi ni kupita printf, thamani.

653
00:28:55,670 --> 00:28:58,000
Na, kwa kweli, nilifanya typo kidogo hapa.

654
00:28:58,000 --> 00:28:59,850
Lakini hiyo ni kwa urahisi fasta.

655
00:28:59,850 --> 00:29:02,390
Napenda kuongeza katika, i hapa.

656
00:29:02,390 --> 00:29:06,150
Kwa sasa tuna printf kuwa
kupita kwamba thamani placeholder.

657
00:29:06,150 --> 00:29:08,299
Na nini kinaendelea kuhesabu juu kupitia?

658
00:29:08,299 --> 00:29:08,840
Watazamaji: 50.

659
00:29:08,840 --> 00:29:09,340
50.

660
00:29:09,340 --> 00:29:10,160
49.

661
00:29:10,160 --> 00:29:10,910
DAVID J Malan: 49.

662
00:29:10,910 --> 00:29:13,340
Hivyo 50, katika mtazamo wa kwanza, inaonekana haki.

663
00:29:13,340 --> 00:29:16,990
Lakini hiyo, ni zamu nje, ni kwenda kuwa
hali yetu kwamba sisi kuendelea kuangalia.

664
00:29:16,990 --> 00:29:21,740
Na tunakwenda kuacha mara moja
i ni tena chini ya 50.

665
00:29:21,740 --> 00:29:24,920
Hivyo kitanzi hii, kinyume chake, lazima
kutekeleza, hivyo muda mrefu kama i ni chini ya 50.

666
00:29:24,920 --> 00:29:28,891
Lakini kwa haraka kama inakuwa 50, au 51,
au mbaya, ni lazima kuacha moja kwa moja.

667
00:29:28,891 --> 00:29:29,390
Wote haki.

668
00:29:29,390 --> 00:29:31,200
>> Hivyo nini hasa kinatokea hapa?

669
00:29:31,200 --> 00:29:33,160
Hivyo hii ni amri ya
shughuli kwa kitanzi.

670
00:29:33,160 --> 00:29:35,440
Moja, una
kinachojulikana initialization.

671
00:29:35,440 --> 00:29:38,264
Hii njano yalionyesha chunk
wa kanuni ni kunyongwa kwanza,

672
00:29:38,264 --> 00:29:40,930
na ina athari kwamba, kwa
Jumatano, pengine kufikiria.

673
00:29:40,930 --> 00:29:45,500
Ni inajenga variable kuitwa i na ni
Maduka kwa kuwa kutofautiana thamani 0.

674
00:29:45,500 --> 00:29:47,560
Hivyo i ni 0 katika hatua hii katika hadithi.

675
00:29:47,560 --> 00:29:49,680
>> Jambo la pili kwamba
hutokea katika kujenga huu,

676
00:29:49,680 --> 00:29:51,540
ni kwamba hali anapata checked.

677
00:29:51,540 --> 00:29:54,325
Hivyo mimi kuangalia mara moja,
ni i chini ya 50?

678
00:29:54,325 --> 00:29:57,700
Na bila shaka, jibu
kwa sasa ni, bila shaka, ndiyo.

679
00:29:57,700 --> 00:30:00,710
Ndiyo, kwa sababu i ni 0, na
hiyo ni hakika chini ya 50.

680
00:30:00,710 --> 00:30:03,866
Kisha nini kinatokea, ni kwamba hii
mstari wa kanuni anapata kunyongwa.

681
00:30:03,866 --> 00:30:06,740
Na kwa kweli, kama kuna nyingi
mstari wa kanuni katika braces wale curly,

682
00:30:06,740 --> 00:30:09,020
wote kupata kuuawa mmoja baada ya mwingine.

683
00:30:09,020 --> 00:30:11,450
>> Na katika athari hapa, ni
inaonekana, magazeti nje

684
00:30:11,450 --> 00:30:15,365
idadi i, ambayo ni kwenda
0, na kisha 1, na kisha 2.

685
00:30:15,365 --> 00:30:15,865
Lakini kwa nini?

686
00:30:15,865 --> 00:30:17,410
Kwa nini ni kupata incremented?

687
00:30:17,410 --> 00:30:20,680
Naam, jambo la nne kwamba
kinachotokea ni kwamba syntax hii

688
00:30:20,680 --> 00:30:22,610
anapata kunyongwa, baada ya semicolon.

689
00:30:22,610 --> 00:30:27,506
i ++ ni njia shorthand ya kusema;
kuchukua thamani ya i, na kuongeza 1 kwa hivyo;

690
00:30:27,506 --> 00:30:30,380
na kisha mara ya pili karibu, kuongeza
1 kwa hilo, na wakati mwingine kote,

691
00:30:30,380 --> 00:30:31,330
kuongeza 1 na hiyo.

692
00:30:31,330 --> 00:30:33,640
>> Hivyo kama sisi kuendelea na safari,
nini kitatokea

693
00:30:33,640 --> 00:30:35,890
pili ni Sitakuja kwa
initialize i milele tena.

694
00:30:35,890 --> 00:30:38,290
Kama mimi naendelea initializing
i 0, mfano huu

695
00:30:38,290 --> 00:30:41,110
yasingeli kwisha kwa sababu
i itakuwa kukwama katika 0.

696
00:30:41,110 --> 00:30:43,870
Lakini nini kinaenda kutokea ni
kwamba hali kuchunguzwa,

697
00:30:43,870 --> 00:30:54,280
mstari wa kanuni kupata kunyongwa,
i itakuwa incremented,

698
00:30:54,280 --> 00:30:56,970
hali kuchunguzwa,
kificho kupata kunyongwa.

699
00:30:56,970 --> 00:30:59,790
Na naendelea baiskeli tena,
na tena, na tena,

700
00:30:59,790 --> 00:31:03,340
mpaka i ++ induces thamani ya 50.

701
00:31:03,340 --> 00:31:05,870
>> Hali kisha anasema,
ni 50 chini ya 50?

702
00:31:05,870 --> 00:31:09,360
Jibu, bila shaka, hakuna, na
hivyo kificho zima haachi utekelezaji.

703
00:31:09,360 --> 00:31:13,020
Na kama una kificho zaidi juu ya screen
chini chini, kwamba ni nini kinatokea ijayo.

704
00:31:13,020 --> 00:31:17,530
Pops nje ya hizi braces curly na
inaendelea na magazeti zaidi baada ya hapo.

705
00:31:17,530 --> 00:31:20,470
>> Hivyo utani sasa, kutokana na Foxtrot, kwamba
wewe utakuwa labda sasa kuelewa.

706
00:31:20,470 --> 00:31:30,810

707
00:31:30,810 --> 00:31:31,560
Ni siku zote funny.

708
00:31:31,560 --> 00:31:34,110
Ni kama chuckles
aina ya percolate,

709
00:31:34,110 --> 00:31:38,370
na kisha wewe kutambua hawapaswi
kuwa laughing katika ucheshi kama hii.

710
00:31:38,370 --> 00:31:41,160
Lakini kuna baadhi takeaway
hapa, pedagogically, pia.

711
00:31:41,160 --> 00:31:43,577
Hivyo ni zamu nje kwamba mimi nina
kukosa kipande cha syntax,

712
00:31:43,577 --> 00:31:45,410
au Foxtrot ya kukosa
kipande cha syntax hapa.

713
00:31:45,410 --> 00:31:48,076
Kinachokosekana, kwamba tulikuwa na
katika kila mfano mwingine, hivi sasa?

714
00:31:48,076 --> 00:31:51,599

715
00:31:51,599 --> 00:31:53,390
Kwa upande wake, ni pale, hivyo
hiyo ni kitu kingine,

716
00:31:53,390 --> 00:31:54,440
kwamba tutaweza kurudi kwa kabla ya muda mrefu.

717
00:31:54,440 --> 00:31:55,398
Kinachokosekana, ingawa?

718
00:31:55,398 --> 00:31:55,908
Naam.

719
00:31:55,908 --> 00:31:58,150
>> Watazamaji MEMBER:
initialization ya [inaudible].

720
00:31:58,150 --> 00:31:58,470
>> DAVID J Malan: Sawa.

721
00:31:58,470 --> 00:31:58,980
Hivyo yeah.

722
00:31:58,980 --> 00:32:03,210
Hivyo kweli, hii is-- Naam,
na kuhesabu ni initialized

723
00:32:03,210 --> 00:32:05,470
up hapo juu, au tuseme, alitangaza juu juu.

724
00:32:05,470 --> 00:32:06,960
Hivyo hii ni njia nyingine ya kufanya hivyo.

725
00:32:06,960 --> 00:32:08,685
Lakini si katika mstari mmoja ni halali ingawa.

726
00:32:08,685 --> 00:32:09,310
Vipi kuhusu hapa?

727
00:32:09,310 --> 00:32:10,196
>> Watazamaji MEMBER: Je, ni braces curly?

728
00:32:10,196 --> 00:32:10,640
>> DAVID J Malan: Yeah.

729
00:32:10,640 --> 00:32:12,080
Hivyo braces curly ni kukosa.

730
00:32:12,080 --> 00:32:15,495
Lakini kanuni hii, I mean, kwa mikopo yao,
ni kweli, syntactically halali.

731
00:32:15,495 --> 00:32:17,610
Zinageuka, huna
haja braces curly

732
00:32:17,610 --> 00:32:21,691
kama wewe tu na mstari mmoja wa kificho kwamba
unataka kutekeleza ndani ya kitanzi.

733
00:32:21,691 --> 00:32:24,190
Sasa sisi siku zote, katika darasa na katika
wote wa usambazaji kanuni zetu,

734
00:32:24,190 --> 00:32:26,730
pamoja na braces curly
anyway, tu kwa ajili ufafanuzi wa.

735
00:32:26,730 --> 00:32:29,010
Lakini kutambua kwamba katika vitabu vya kiada
na mifano online,

736
00:32:29,010 --> 00:32:31,300
unaweza vizuri sana angalia curly
inakabiliwa na kukosa muda fulani.

737
00:32:31,300 --> 00:32:34,850
Na hiyo ni sawa, ikiwa nyinyi
kuwa indented na lengo

738
00:32:34,850 --> 00:32:38,650
ni tu line moja ya kanuni, na si
mistari mingi ya kificho, uwezekano.

739
00:32:38,650 --> 00:32:39,150
Wote haki.

740
00:32:39,150 --> 00:32:44,500
Hivyo kuhusiana na suala la
kutokuwa sahihi, ni suala la kufurika,

741
00:32:44,500 --> 00:32:48,560
kwa maana kwamba, vile vile,
Je, integers na mipaka kwao

742
00:32:48,560 --> 00:32:49,970
kama yaliyo maadili uhakika?

743
00:32:49,970 --> 00:32:53,120
Katika dunia hatua yaliyo
maadili, tunaweza tu kuwa hivyo sahihi,

744
00:32:53,120 --> 00:32:55,710
baada ya hapo, wakati mwingine
mambo mabaya yanaweza kutokea,

745
00:32:55,710 --> 00:32:57,760
na mipango yetu inaweza kuwa buggy na makosa.

746
00:32:57,760 --> 00:33:00,050
Sasa hata kwa integers,
unaweza kukimbia katika matatizo.

747
00:33:00,050 --> 00:33:03,820
Sasa integer hana
uhakika decimal au namba baada yake.

748
00:33:03,820 --> 00:33:07,130
Ni tu idadi ya asili, kawaida.

749
00:33:07,130 --> 00:33:09,430
Basi nini inaweza kwenda vibaya na int?

750
00:33:09,430 --> 00:33:12,210
Kama mimi nina kutumia int kwa
kuhesabu, nini inaweza kwenda vibaya?

751
00:33:12,210 --> 00:33:13,230
Inaonekana rahisi sana.

752
00:33:13,230 --> 00:33:13,873
Naam.

753
00:33:13,873 --> 00:33:16,240
>> Watazamaji MEMBER: Kama
idadi anapata [inaudible]

754
00:33:16,240 --> 00:33:17,073
>> DAVID J Malan: Yeah.

755
00:33:17,073 --> 00:33:20,820
Nini kama wewe kuhesabu juu, kwamba wewe
hawezi kueleza kwamba idadi kubwa kweli kweli.

756
00:33:20,820 --> 00:33:21,320
Sawa?

757
00:33:21,320 --> 00:33:23,910
Katika hatua nyingine, wewe ni kwenda
kisichozidi mipaka

758
00:33:23,910 --> 00:33:27,077
ya 32-bit thamani au thamani ya 64-bit.

759
00:33:27,077 --> 00:33:29,410
Sasa tena, mimi nina uhakika jinsi
kutamka thamani ya 64-bit,

760
00:33:29,410 --> 00:33:32,230
lakini najua kwa 32-bit integer,
kubwa thamani inaweza kuwa,

761
00:33:32,230 --> 00:33:35,490
ikiwa ni chanya tu
maadili, ni takribani bilioni 4.

762
00:33:35,490 --> 00:33:39,000
Hivyo kama mimi kujaribu kuhesabu hadi bilioni 5,
kitu ambacho kinaenda kutokea.

763
00:33:39,000 --> 00:33:41,050
Lakini hebu angalia nini, kwa kweli, yanaweza kutokea.

764
00:33:41,050 --> 00:33:44,570
Katika ulimwengu wa integer
kufurika, ambapo, kwa maana,

765
00:33:44,570 --> 00:33:48,270
kufurika uwezo wa
integer, nini kinaweza kutokea?

766
00:33:48,270 --> 00:33:51,190
>> Hivyo hapa ni idadi binary,
ni throwback kwa 0.

767
00:33:51,190 --> 00:33:54,630
Ni wote wa 1, na placeholders
huko, ni nguvu za 2,

768
00:33:54,630 --> 00:33:55,980
hivyo hii ni mapacha.

769
00:33:55,980 --> 00:33:59,416
Basi hizi ni 8, 1 bits kwenye screen.

770
00:33:59,416 --> 00:34:01,290
Na kama unakumbuka au
wewe haraka kufanya hesabu,

771
00:34:01,290 --> 00:34:06,074
thamani kile ni kuwa kuwakilishwa
hapa na haya nane 1 bits?

772
00:34:06,074 --> 00:34:06,950
255.

773
00:34:06,950 --> 00:34:09,260
Na hata kama hawakuwa na uhakika kabisa
ya hisabati, unaweza kufanya hivyo nje.

774
00:34:09,260 --> 00:34:10,550
Au unaweza tu aina
ya sababu kwa njia hiyo,

775
00:34:10,550 --> 00:34:12,633
kusubiri dakika, kama mimi nina
anayewakilisha thamani 8 kidogo,

776
00:34:12,633 --> 00:34:17,750
na mimi nimepata maadili 256 iwezekanavyo,
lakini kwanza ambayo ni 0,

777
00:34:17,750 --> 00:34:19,909
Mimi tu kujua kwamba
kubwa ni kwenda kuwa 255,

778
00:34:19,909 --> 00:34:21,510
na hilo ndilo huu mtu anaweza kuwa.

779
00:34:21,510 --> 00:34:26,060
>> Hivyo nadhani kujaribu kuongeza 1 kwa thamani hiyo.

780
00:34:26,060 --> 00:34:28,750
Je utafanya nini katika daraja
shule wakati akiongeza 1, na ni

781
00:34:28,750 --> 00:34:31,139
kweli haina fit kwa sababu
una kubeba 1?

782
00:34:31,139 --> 00:34:34,380
Ni nini idadi hii kwenda
kuwa wakati kuongeza 1?

783
00:34:34,380 --> 00:34:37,030
Ni kwenda kuwa 0.

784
00:34:37,030 --> 00:34:37,530
Sawa?

785
00:34:37,530 --> 00:34:41,139
Kwa sababu kama alikuwa na zaidi bits-- na mimi itabidi
kujaribu, aina ya, aina yake nje here--

786
00:34:41,139 --> 00:34:44,710
kama tulikuwa na bits zaidi, nini sisi
anaweza kufanya hapa ni kuongeza 1,

787
00:34:44,710 --> 00:34:47,370
na kisha tunatarajia kupata hii.

788
00:34:47,370 --> 00:34:48,739
Whoops.

789
00:34:48,739 --> 00:34:52,250
Tunatarajia kuwa 1 bit njia yote juu hapa.

790
00:34:52,250 --> 00:34:55,530
>> Lakini kama hii ni mahususi
thamani, ni bits 8 tu,

791
00:34:55,530 --> 00:34:57,480
na kwamba kabla ya kuamua
na kompyuta,

792
00:34:57,480 --> 00:34:59,370
kuwa 1 ni ufanisi si huko.

793
00:34:59,370 --> 00:35:00,980
Ni aina tu ya maporomoko mbali Cliff.

794
00:35:00,980 --> 00:35:05,480
Na hivyo kama wewe kuongeza 1 kwa 255, nini
thamani do you inaonekana kupata?

795
00:35:05,480 --> 00:35:06,180
0.

796
00:35:06,180 --> 00:35:09,700
Na hivyo idadi ajali,
na pengine, bila kukusudia,

797
00:35:09,700 --> 00:35:12,040
kuishia wrapping karibu kama hii.

798
00:35:12,040 --> 00:35:14,079
Sasa ni nini kinaweza kuwa maana ya hii?

799
00:35:14,079 --> 00:35:15,620
Naam, kuna mambo kadhaa tofauti.

800
00:35:15,620 --> 00:35:18,751
Hivyo moja, haina kuishia kuangalia
kama 0, bila kukusudia,

801
00:35:18,751 --> 00:35:20,750
lakini unaweza aina ya kuona,
hata katika ulimwengu wa kweli,

802
00:35:20,750 --> 00:35:23,416
kwa bora au mbaya,
maonyesho ya wazo hili la kikomo.

803
00:35:23,416 --> 00:35:26,630
Kwa mfano, mtu yeyote kati yenu ambaye
wamewahi kucheza Lego Star Wars,

804
00:35:26,630 --> 00:35:28,880
haina mtu yeyote kutokea kwa kujua
upeo wa idadi ya sarafu

805
00:35:28,880 --> 00:35:32,032
unaweza kukusanya katika Lego Star Wars?

806
00:35:32,032 --> 00:35:35,640
Kuchukua nadhani kulingana na
maswali ya leo kuongoza.

807
00:35:35,640 --> 00:35:39,140
Ni kubwa kuliko 256 au 255.

808
00:35:39,140 --> 00:35:40,330
Ni bilioni 4.

809
00:35:40,330 --> 00:35:42,080
Hivyo ni zamu nje, na
kuna baadhi people--

810
00:35:42,080 --> 00:35:46,080
baadhi googling alithibitisha jana night--
waliopata bilioni 4 dhahabu sarafu,

811
00:35:46,080 --> 00:35:47,730
au whatnot, katika Lego Star Wars.

812
00:35:47,730 --> 00:35:49,860
Ingawa inaonekana, kuna
njia ya hila mchezo,

813
00:35:49,860 --> 00:35:53,222
kuna mdudu au kipengele, ambayo inakuwezesha
tu inaingia kura na kura ya pointi.

814
00:35:53,222 --> 00:35:54,930
Lakini kubwa iwezekanavyo
thamani, kwa mujibu

815
00:35:54,930 --> 00:35:58,360
screen hii risasi ya mtu mimi
kupatikana online, ni kweli, bilioni 4.

816
00:35:58,360 --> 00:35:59,240
>> Sasa kwa nini ni kwamba?

817
00:35:59,240 --> 00:36:03,040
Ni just bilioni 4,
pengine kwa sababu mtu aliamua,

818
00:36:03,040 --> 00:36:05,500
ambao alikuwa anaandika mchezo huu,
waweze kufanya bilioni 4,

819
00:36:05,500 --> 00:36:07,340
kitu, kitu, kitu,
kama mimi kuweka thamani

820
00:36:07,340 --> 00:36:10,256
na calculator awali, lakini
ni tu safi kidogo kwa ajili ya binadamu

821
00:36:10,256 --> 00:36:12,610
kusema upeo wa idadi
ya coins-- au studs,

822
00:36:12,610 --> 00:36:14,860
kwani simu them-- kwamba
unaweza kukusanya ni bilioni 4.

823
00:36:14,860 --> 00:36:16,290
Na hivyo, kwa nini hii?

824
00:36:16,290 --> 00:36:20,310
Jinsi ni mchezo LEGO
utekelezaji wa kukabiliana na

825
00:36:20,310 --> 00:36:23,420
hiyo ni kuweka wimbo wa
idadi ya sarafu una?

826
00:36:23,420 --> 00:36:24,266
Wao ni kutumia nini?

827
00:36:24,266 --> 00:36:26,390
Watazamaji MEMBER: Ni ataacha
kuhesabu baada ya bilioni 4.

828
00:36:26,390 --> 00:36:27,720
DAVID J Malan: Ni ataacha
kuhesabu baada ya bilioni 4,

829
00:36:27,720 --> 00:36:29,525
ambayo ina maana unaweza
kudai, kama programu,

830
00:36:29,525 --> 00:36:31,960
kwamba wao ni pengine
kutumia 32 kidogo integer.

831
00:36:31,960 --> 00:36:35,380
Kama programu literally tu
typed, int, katika kanuni zake,

832
00:36:35,380 --> 00:36:39,620
na kwamba aina ya kutofautiana kwamba
wao ni kutumia kuhifadhi kificho mtu.

833
00:36:39,620 --> 00:36:42,230
Hivyo kuna dalili zingine
wa aina hii ya mipaka.

834
00:36:42,230 --> 00:36:45,063
>> Hivyo mimi si kucheza game-- hii
na mimi nilikuwa kusoma juu ya historia

835
00:36:45,063 --> 00:36:48,470
kuthibitisha kama much-- lakini katika
toleo la awali la Ustaarabu, ambapo

836
00:36:48,470 --> 00:36:53,240
wewe inaonekana kuingiliana na kila
wengine na wanaweza kupigana vita au amani,

837
00:36:53,240 --> 00:36:56,590
Gandhi ilitakiwa kuwa moja ya
wahusika zaidi ya amani, kama mimi

838
00:36:56,590 --> 00:36:59,280
kuelewa, katika kwanza
toleo la Civilization.

839
00:36:59,280 --> 00:37:03,250
Na kwa kweli, juu ya kipimo cha 1 mpaka 10,
uchokozi wake mara tu 1.

840
00:37:03,250 --> 00:37:05,620
Hivyo milele hivyo kwa upole
fujo, inaonekana.

841
00:37:05,620 --> 00:37:11,590
>> Lakini wakati fulani, unaweza dhahiri
kufunga demokrasia nchini Jiografia yako.

842
00:37:11,590 --> 00:37:14,900
Na kama wewe kufunga demokrasia
ndani ya toleo yako ya mchezo,

843
00:37:14,900 --> 00:37:17,320
kisha uchokozi wako ngazi inakwenda chini.

844
00:37:17,320 --> 00:37:18,460
Ni jambo zuri.

845
00:37:18,460 --> 00:37:20,890
Watu ni zaidi utulivu
inaonekana, katika hali hiyo.

846
00:37:20,890 --> 00:37:23,190
Lakini inaonekana, mtu alifanya
na kitu, ikiwa, hali

847
00:37:23,190 --> 00:37:24,780
katika toleo asili ya kificho.

848
00:37:24,780 --> 00:37:30,650
>> Hivyo Gandhi uchokozi cha akaenda kutoka
chanya 1, bala 2, kwa hasi 1,

849
00:37:30,650 --> 00:37:33,840
lakini mchezo hana
kuelewa idadi hasi.

850
00:37:33,840 --> 00:37:38,680
Kwa hiyo kile kilichotokea ilikuwa uchokozi Gandhi
kiwango cha akaenda kutoka 1, 0, kwa hasi 1,

851
00:37:38,680 --> 00:37:40,900
ambayo ilikuwa na athari ya
wrapping karibu na kuwa

852
00:37:40,900 --> 00:37:44,690
tabia fujo zaidi
katika mchezo, wakati thamani ya 255,

853
00:37:44,690 --> 00:37:46,630
juu ya kipimo cha 1 mpaka 10.

854
00:37:46,630 --> 00:37:49,887
Na tangu wakati huo, kumekuwa na
incarnations zaidi ya mchezo huu,

855
00:37:49,887 --> 00:37:51,720
na wameweza agizo hilo kama
aina ya Pasaka mayai,

856
00:37:51,720 --> 00:37:53,870
kwamba Gandhi ni inaonekana
hivyo sana fujo.

857
00:37:53,870 --> 00:37:56,740
Lakini ilikuwa ni matokeo ya
Programu makosa rahisi sana

858
00:37:56,740 --> 00:37:58,630
katika kwamba toleo mapema sana ya mchezo.

859
00:37:58,630 --> 00:38:02,860
>> Sasa zaidi disturbingly, zaidi
Hivi karibuni, Boeing 787

860
00:38:02,860 --> 00:38:05,720
ilikuwa kumbukumbu kama kuwa
mdudu, si aina ya kifaa

861
00:38:05,720 --> 00:38:07,340
wewe hasa nataka kuwa na mdudu.

862
00:38:07,340 --> 00:38:10,130
Na dalili kwamba nita kusoma
hapa, kutoka makala online,

863
00:38:10,130 --> 00:38:13,840
ilikuwa hii, mfano ndege 787
ambayo imekuwa inaendeshwa kuendelea

864
00:38:13,840 --> 00:38:18,030
kwa muda wa siku 248 wanaweza kupoteza wote
mchanganyiko wa sasa, AC,

865
00:38:18,030 --> 00:38:20,850
nguvu za umeme, kutokana na
vitengo vya kudhibiti jenereta,

866
00:38:20,850 --> 00:38:23,330
GCUs, wakati huo huo
kwenda katika mkao wa tahadhari.

867
00:38:23,330 --> 00:38:26,790
Hivyo hii ilikuwa onyo iliyotolewa
wakati tatizo hili iligundulika.

868
00:38:26,790 --> 00:38:28,750
Hali hii inasababishwa
na programu ya kukabiliana,

869
00:38:28,750 --> 00:38:32,230
ndani ya GCUs, hivyo
integer au kutofautiana,

870
00:38:32,230 --> 00:38:36,850
kwamba mapenzi kufurika baada 248
siku ya madaraka kuendelea.

871
00:38:36,850 --> 00:38:40,350
Boeing iko katika mchakato wa
kuendeleza GCU programu ya kuboresha kwamba

872
00:38:40,350 --> 00:38:42,350
itakuwa kukabiliana na hali salama.

873
00:38:42,350 --> 00:38:44,226
>> Sana kama kombora
mazingira, eti

874
00:38:44,226 --> 00:38:46,850
walikuwa na aina fulani ya kutofautiana
kwamba alikuwa kuhesabu, na kuhesabu,

875
00:38:46,850 --> 00:38:50,720
na kuhesabu, lakini hatua kwa hatua imejazwa
mipaka ya uwezo wake,

876
00:38:50,720 --> 00:38:54,890
vile vile alivyofanya ndege damn
na kufurika kutofautiana

877
00:38:54,890 --> 00:38:56,410
baada ya muda wa kutosha wa mbio.

878
00:38:56,410 --> 00:38:59,240
Na hivyo ulimi-katika-shavu njia
ya kufanya kazi kwa karibu suala hili

879
00:38:59,240 --> 00:39:04,400
ni kwa kweli, reboot, ndege yako kila
Siku 247, ili kumbukumbu anapata kufutika

880
00:39:04,400 --> 00:39:06,100
na kutofautiana anarejea 0.

881
00:39:06,100 --> 00:39:09,410
Lakini kutambua, hii ni sana
mwili kubwa ya programu,

882
00:39:09,410 --> 00:39:14,070
lakini hasa kama sisi kusikia kuhusu Apple
mifumo ya uendeshaji kwenda katika magari,

883
00:39:14,070 --> 00:39:18,030
na kujitegemea kuendesha magari kutoka Google, na
idadi yoyote ya incarnations ya programu

884
00:39:18,030 --> 00:39:21,000
katika maisha ya kila siku yetu, TV
na kuona, na zaidi,

885
00:39:21,000 --> 00:39:24,950
kutambua walikuwa kuzungukwa na programu,
yote ambayo imeandikwa na sisi binadamu.

886
00:39:24,950 --> 00:39:28,150
>> Na kama tutaweza wote karibuni kugundua,
ni rahisi sana na kawaida sana

887
00:39:28,150 --> 00:39:30,250
kufanya makosa wakati wa kuandika programu.

888
00:39:30,250 --> 00:39:32,745
Na kama huna kuwakamata,
baadhi ya mambo mabaya yanaweza kutokea.

889
00:39:32,745 --> 00:39:35,400
Sasa wakati mwingine, baadhi
mambo funny yanaweza kutokea,

890
00:39:35,400 --> 00:39:38,280
au angalau wakati mwingine sisi
kujua cha kutarajia baadhi ubaya.

891
00:39:38,280 --> 00:39:41,550
Hivyo 0 kugawanywa na 0, kutoka daraja
shule, kwa ujumla ni jambo baya.

892
00:39:41,550 --> 00:39:43,050
Ni kisichojulikana.

893
00:39:43,050 --> 00:39:46,440
Na ni zamu nje na hebu angalia kama
mic yangu anaweza kuchukua hii up-- kwamba Apple

894
00:39:46,440 --> 00:39:47,790
alikuwa na baadhi ya furaha na hii hivi karibuni.

895
00:39:47,790 --> 00:39:48,850
Hivyo nina iPhone hapa.

896
00:39:48,850 --> 00:39:54,160
Mimi nina kwenda kuzungumza na Siri na kuuliza yake
kunipa jibu la 0 kugawanywa na 0.

897
00:39:54,160 --> 00:39:55,850
Kile ni 0 kugawanywa na 0?

898
00:39:55,850 --> 00:39:59,350

899
00:39:59,350 --> 00:40:02,230
>> Siri: Fikiria kuwa una 0
biskuti, na wewe kupasuliwa yao sawasawa

900
00:40:02,230 --> 00:40:03,540
miongoni mwa 0 marafiki.

901
00:40:03,540 --> 00:40:05,810
Jinsi kuki wengi haina kila mtu kupata?

902
00:40:05,810 --> 00:40:06,350
Kuona kitu gani?

903
00:40:06,350 --> 00:40:07,660
Ni haina mantiki.

904
00:40:07,660 --> 00:40:10,540
Na Cookie Monster Inasikitisha
kuwa hakuna biskuti.

905
00:40:10,540 --> 00:40:13,987
Na wewe ni huzuni kwamba
wewe huna marafiki.

906
00:40:13,987 --> 00:40:15,570
DAVID J Malan: Ni aina ya obnoxious.

907
00:40:15,570 --> 00:40:17,550
Hivyo hii ni nini mara tu alisema kuna.

908
00:40:17,550 --> 00:40:21,380
Ni indeterminate, siyo inavyoelezwa,
na kwa kweli, lugha nyingi programu

909
00:40:21,380 --> 00:40:24,950
au, kwa kweli, compilers mapenzi
kuchunguza wakati wewe, katika mpango,

910
00:40:24,950 --> 00:40:27,050
kujaribu kugawanya 0 na 0.

911
00:40:27,050 --> 00:40:29,830
Furaha zaidi kuliko ingawa hii, ni
kwamba inaonekana, Cookie Monster

912
00:40:29,830 --> 00:40:31,270
ni juu ya Twitter siku hizi.

913
00:40:31,270 --> 00:40:37,610
Naye akajibu kwa hii, na hii,
ambayo ni adorable kabisa.

914
00:40:37,610 --> 00:40:40,110
Lakini hebu tuangalie kwa haraka katika
michache ya constructs mengine,

915
00:40:40,110 --> 00:40:43,459
na kisha kuweka baadhi ya hii
kificho kwa matumizi, kwa njia nzuri.

916
00:40:43,459 --> 00:40:45,250
Hivyo ni zamu nje, badala ya
kwa mizunguko, kuna

917
00:40:45,250 --> 00:40:49,174
kitu kinachoitwa kitanzi wakati, kwamba
inaonekana tofauti na unatekelezwa

918
00:40:49,174 --> 00:40:51,590
differently-- kidogo na
tutaweza hatimaye kuona examples--

919
00:40:51,590 --> 00:40:53,500
lakini katika baadhi ya hisia,
ni rahisi kwa sababu ni

920
00:40:53,500 --> 00:40:56,670
haina kuruhusu initialize na
update ndani ya mipaka ya kitanzi.

921
00:40:56,670 --> 00:40:57,794
Bado unaweza kutekeleza.

922
00:40:57,794 --> 00:41:01,219
Hivyo unaweza kufanya halisi mambo sawa
kwa kitanzi wakati, kama ilivyo kwa ajili ya kitanzi,

923
00:41:01,219 --> 00:41:03,260
lakini syntax yako, ultimately--
kama tutaweza hatimaye

924
00:41:03,260 --> 00:41:04,551
see-- ni kwenda kuwa tofauti.

925
00:41:04,551 --> 00:41:07,450
Kuna hata kufanya wakati kitanzi, ambayo
ni kweli tofauti kidogo,

926
00:41:07,450 --> 00:41:09,640
kwa kuwa wakati kwa kitanzi
na kitanzi wakati daima

927
00:41:09,640 --> 00:41:13,005
kuangalia hali yao ya kwanza, kama
kusoma hii juu Jambo hadi chini,

928
00:41:13,005 --> 00:41:16,440
ni aina ya inaonekana kama ni kwenda
kuangalia ni ya hali ya mwisho kwa sababu ni

929
00:41:16,440 --> 00:41:17,910
kweli mstari wa mwisho wa kanuni.

930
00:41:17,910 --> 00:41:20,580
Na hakika, hiyo ni kwenda kuwa na manufaa
katika mipango fulani kwamba sisi kuandika,

931
00:41:20,580 --> 00:41:23,746
kama unataka tu upofu kufanya kitu
na hatimaye kuangalia hali.

932
00:41:23,746 --> 00:41:25,205
Hiyo ni si lazima kitu mbaya.

933
00:41:25,205 --> 00:41:27,912
Kama tunataka vigezo, tunaweza kufanya
hivyo katika michache ya njia tofauti.

934
00:41:27,912 --> 00:41:30,290
Na tuliona katika Foxtrot
cartoon, njia moja ya kufanya hivyo,

935
00:41:30,290 --> 00:41:33,400
ambapo kutangaza kutofautiana yako,
kama int kukabiliana semicolon,

936
00:41:33,400 --> 00:41:36,570
na kisha later-- labda ijayo
line, labda mistari 10 later--

937
00:41:36,570 --> 00:41:37,800
wewe kweli initialize.

938
00:41:37,800 --> 00:41:42,230
Basi hizi mistari 2 ya maadili
kutangaza kutofautiana wa aina int

939
00:41:42,230 --> 00:41:44,930
na kuiita kukabiliana, hivyo ni inatoa
mimi bits kutosha kushikilia int.

940
00:41:44,930 --> 00:41:48,230
Na kisha hatimaye, unaweka
thamani 0 ndani ya kwamba kutofautiana.

941
00:41:48,230 --> 00:41:51,250
Ni anapanga 0 na 1 katika
mfano, kwa kuwa tunajua kutoka wiki iliyopita,

942
00:41:51,250 --> 00:41:53,260
inawakilisha idadi tunajua kama 0.

943
00:41:53,260 --> 00:41:56,920
Au kusema ukweli, unaweza kufanya kiasi hiki
zaidi ufupi, tu kama hii.

944
00:41:56,920 --> 00:41:59,390
>> Sasa sisi pia kuwa
uwezo wa kupiga kazi.

945
00:41:59,390 --> 00:42:03,070
Na kwa kweli, hapa ni 2 line
mpango, au Excerpt vyake,

946
00:42:03,070 --> 00:42:06,157
ambayo inaruhusu sisi kweli
kuandika baadhi kificho kwamba

947
00:42:06,157 --> 00:42:08,990
anapata kamba kutoka user-- sana
kama kujitolea yetu sasa ago--

948
00:42:08,990 --> 00:42:11,320
kuhifadhi matokeo katika
kutofautiana kuitwa jina,

949
00:42:11,320 --> 00:42:15,470
na then-- kiasi kama kwa kujitolea wetu
na printf-- prints nje maadili hayo

950
00:42:15,470 --> 00:42:19,180
kwa kupita katika hoja mbili,
kamba, ikifuatiwa na kutofautiana

951
00:42:19,180 --> 00:42:20,781
kuitwa, jina, yenyewe.

952
00:42:20,781 --> 00:42:23,155
Hivyo hebu tuangalie, kabla
sisi kuja huko nyuma Mario,

953
00:42:23,155 --> 00:42:26,010
katika michache ya sasa, mifano ya hili.

954
00:42:26,010 --> 00:42:30,537
>> Mimi nina kwenda kwenda mbele na kufungua
up, hebu sema, kazi-0.c.

955
00:42:30,537 --> 00:42:33,120
Na kama siku zote, kanuni na hii ni
inapatikana kwenye tovuti kozi ya,

956
00:42:33,120 --> 00:42:35,660
hivyo unaweza kucheza pamoja katika
nyumbani na kuangalia ni baadaye.

957
00:42:35,660 --> 00:42:40,400
Lakini hapa ni mpango katika ni
Kimsingi, kutokana na mstari 17 na 22.

958
00:42:40,400 --> 00:42:43,270
Mpango kuu ni wapi
mpango ni daima kwenda kuanza.

959
00:42:43,270 --> 00:42:46,980
Mpango huu, inaonekana, ni kwenda
magazeti nje jina lako, matumbo.

960
00:42:46,980 --> 00:42:50,320
Ni kisha kwenda kuwaita GetString,
kama tulivyofanya kwa kujitolea yetu.

961
00:42:50,320 --> 00:42:53,365
Na kisha, hii ni ya kuvutia,
ni kwenda kuwaita PrintName.

962
00:42:53,365 --> 00:42:56,490
Zinageuka, muda wote huu, kuna
Inaonekana kuwa kazi kuitwa PrintName.

963
00:42:56,490 --> 00:42:57,614
Kwamba Prints jina la mtu.

964
00:42:57,614 --> 00:43:01,210
Sisi hakuwa na haja ya kutumia printf kutoka
yesteryear, kuna PrintName.

965
00:43:01,210 --> 00:43:03,500
>> Lakini hiyo ni kupotosha
kwa sababu PrintName hana

966
00:43:03,500 --> 00:43:06,760
kuja na C. Watu hakuwa
mzulia ni baadhi 40 au miaka 50 iliyopita,

967
00:43:06,760 --> 00:43:07,990
Mimi, badala yake.

968
00:43:07,990 --> 00:43:10,330
Na kwa kweli, kama mimi kitabu
chini zaidi, ilani

969
00:43:10,330 --> 00:43:14,200
jinsi gani naweza kuandika yangu mwenyewe
kazi katika C. Sisi itabidi hatimaye

970
00:43:14,200 --> 00:43:16,319
kueleza kwa nini sisi kuendelea kusema,
batili, katika maeneo machache,

971
00:43:16,319 --> 00:43:18,110
lakini kwa leo, hebu
tu kuangalia jina.

972
00:43:18,110 --> 00:43:20,905
>> On line 24, kama unataka
kujenga kazi yako mwenyewe,

973
00:43:20,905 --> 00:43:22,780
wewe literally kuandika
jina la kazi.

974
00:43:22,780 --> 00:43:24,340
Nilichagua PrintName.

975
00:43:24,340 --> 00:43:26,159
Katika mabano, wewe
kisha kutaja ni aina gani

976
00:43:26,159 --> 00:43:28,450
wa pembejeo, na jinsi wengi
wanataka kazi hii kwa kuchukua.

977
00:43:28,450 --> 00:43:31,906
Katika kesi hiyo, nataka kuchukua
1 kutofautiana kuitwa, jina,

978
00:43:31,906 --> 00:43:34,030
nayo itakuja kuwa ya
aina, kamba, hivyo ni kwenda

979
00:43:34,030 --> 00:43:35,780
kuwa baadhi mlolongo wa wahusika.

980
00:43:35,780 --> 00:43:39,170
Na kisha, hii program--
kiasi kama katika Scratch,

981
00:43:39,170 --> 00:43:42,590
unaweza kuwa na desturi puzzle pieces--
ni kwenda na tabia hii desturi.

982
00:43:42,590 --> 00:43:46,760
Ni kwenda kuwaita printf
kupita katika, hodi, placeholder,

983
00:43:46,760 --> 00:43:49,110
na basi ni kwenda kuziba
katika chochote mtumiaji kuitwa.

984
00:43:49,110 --> 00:43:51,450
>> Hivyo hii ni mfano wa nini
mwanasayansi kompyuta ingekuwa

985
00:43:51,450 --> 00:43:55,090
wito uchukuaji au kazi
mtengano, ambayo ni haki

986
00:43:55,090 --> 00:43:58,110
njia dhana ya saying-- Je, ikiwa
wewe kama hii wazo kiwango cha juu,

987
00:43:58,110 --> 00:44:01,569
kama nataka utendaji kwamba
Prints jina la mtu, kabisa wewe

988
00:44:01,569 --> 00:44:04,360
unaweza literally kuandika printf na kisha
kupita katika hoja unataka,

989
00:44:04,360 --> 00:44:07,340
na mpango wa kazi,
kama yalivyokuwa tangu Jumatano.

990
00:44:07,340 --> 00:44:10,510
Lakini unaweza kuanza kwa abstract mbali
dhana ya uchapishaji jina.

991
00:44:10,510 --> 00:44:13,270
Unaweza kuwapa jina,
kama PrintName, na hii

992
00:44:13,270 --> 00:44:15,280
ni wazo hili la layering kutoka wiki 0.

993
00:44:15,280 --> 00:44:19,910
>> Tangu sasa, mimi na wewe huna kujua
au huduma jinsi PrintName ni kutekelezwa.

994
00:44:19,910 --> 00:44:22,470
Ndiyo anatumia printf, labda ni
hana, ambaye anajua nini anatumia?

995
00:44:22,470 --> 00:44:23,410
Nani anayejali?

996
00:44:23,410 --> 00:44:26,034
Sasa mimi kuzungumza juu hapa,
badala ya chini hapa.

997
00:44:26,034 --> 00:44:28,700
Na hakika, kama mipango yetu kupata
zaidi ya juu na kisasa,

998
00:44:28,700 --> 00:44:32,550
tunakwenda kuweka kuchukua kwa nafasi
kuwa chini ya vipande puzzle cha kuwepo.

999
00:44:32,550 --> 00:44:34,780
Kwa sababu sisi aliandika yao
au mtu mwingine ye yote, ili

1000
00:44:34,780 --> 00:44:36,910
tuweze kisha kujenga juu yao.

1001
00:44:36,910 --> 00:44:39,430
Hebu tuangalie hii
lahaja, kazi moja.

1002
00:44:39,430 --> 00:44:41,780
>> Hivyo hii moja kidogo zaidi
juu, lakini zinageuka

1003
00:44:41,780 --> 00:44:44,570
kwamba katika maktaba CS50,
kuna tu GetInt kazi.

1004
00:44:44,570 --> 00:44:47,720
Sisi hakufikiri, miaka iliyopita, kwa
kutekeleza kazi GetPositiveInt.

1005
00:44:47,720 --> 00:44:50,970
Na hiyo ndiyo kidogo annoying kwa sababu kama
nyie ni kuandika mpango eti

1006
00:44:50,970 --> 00:44:53,325
unataka kupata chanya
integer kutoka kwa mtumiaji,

1007
00:44:53,325 --> 00:44:55,010
unaweza kabisa kutumia GetInt.

1008
00:44:55,010 --> 00:44:57,840
Na unaweza kabisa kuangalia kwa
hali na labda kitanzi

1009
00:44:57,840 --> 00:45:00,320
kama kwamba int ni mkubwa
kuliko 0 na kelele mtumiaji

1010
00:45:00,320 --> 00:45:02,699
kama yeye au yeye haitoi
wewe idadi chanya.

1011
00:45:02,699 --> 00:45:04,740
Lakini hebu kujenga hii
jengo kuzuia wenyewe,,

1012
00:45:04,740 --> 00:45:06,555
desturi Scratch kipande, kama wewe.

1013
00:45:06,555 --> 00:45:08,680
Mimi nina kwenda kuwa na mpango
hapa kwamba hatimaye, mimi

1014
00:45:08,680 --> 00:45:11,780
wanataka kuwa na uwezo wa kuwaita
GetPositiveInt, na mimi nataka kuwa

1015
00:45:11,780 --> 00:45:14,200
uwezo wa magazeti nje chochote kile int ni.

1016
00:45:14,200 --> 00:45:16,240
Lakini hii ni sehemu ya makala mbali sasa.

1017
00:45:16,240 --> 00:45:19,050
Ni tu amepewa kiwango cha juu
jina kwamba anasema kile yake,

1018
00:45:19,050 --> 00:45:21,780
ambayo ni ya ajabu kwa sababu ni
Intuitive sana sasa kusoma.

1019
00:45:21,780 --> 00:45:24,710
Na kama mimi kufanya huduma nini chini
kofia, basi mimi kitabu chini.

1020
00:45:24,710 --> 00:45:27,140
Na ni kidogo vitisho
mara ya kwanza, hasa

1021
00:45:27,140 --> 00:45:29,470
kama hii ni mpango wako wa kwanza,
lakini hebu tuangalie.

1022
00:45:29,470 --> 00:45:32,860
>> Mimi tena akisema, batili,
kwa sababu ni zamu nje kazi,

1023
00:45:32,860 --> 00:45:34,777
kiasi kama GetString, unaweza
kurudi thamani kwangu.

1024
00:45:34,777 --> 00:45:36,610
Hawana tu na
magazeti kwa screen,

1025
00:45:36,610 --> 00:45:38,410
kwa kweli unaweza mkono
mimi kitu nyuma.

1026
00:45:38,410 --> 00:45:41,535
Na ambapo kabla PrintName,
Mimi hakuwa na haja ya kitu chochote nyuma.

1027
00:45:41,535 --> 00:45:44,160
Mimi zinahitajika athari upande wa
kitu kuonyesha juu kwenye screen,

1028
00:45:44,160 --> 00:45:46,570
lakini mimi hakuwa na haja ya binadamu
kwa mkono mimi kitu nyuma.

1029
00:45:46,570 --> 00:45:48,840
Hapa, kwa GetPositiveInt,
kama na GetInt,

1030
00:45:48,840 --> 00:45:50,640
Nataka kuwa mitupu kitu nyuma.

1031
00:45:50,640 --> 00:45:53,220
Hivyo mimi kusema hivyo, batili,
kwenye mstari 23, lakini int,

1032
00:45:53,220 --> 00:45:55,570
inayosema, kazi hii
kwamba mimi kuandika,

1033
00:45:55,570 --> 00:45:58,860
aitwaye GetPositiveInt ni kwenda
mkono yangu nyuma integer, si kitu,

1034
00:45:58,860 --> 00:45:59,890
si batili.

1035
00:45:59,890 --> 00:46:03,280
>> Wakati huo huo, ni kwenda kuchukua hakuna
pembejeo, hivyo nimekuwa, aina ya, kuachwa yake.

1036
00:46:03,280 --> 00:46:08,280
Mimi si kutoa GetPositiveInt yoyote
pembejeo, mimi nataka unipe matokeo yake.

1037
00:46:08,280 --> 00:46:09,800
Na kisha nini kinatokea sasa?

1038
00:46:09,800 --> 00:46:11,640
Hivyo hapa ni jinsi gani naweza kutangaza kutofautiana.

1039
00:46:11,640 --> 00:46:15,090
Mimi tumefanya ni nje ya kitanzi,
kwa sababu tutaweza hatimaye kuona,

1040
00:46:15,090 --> 00:46:17,700
lakini hii inatoa tu
mimi 32 bits kuitwa, n,

1041
00:46:17,700 --> 00:46:20,952
na nimekuwa awali kuamua
nao kuhifadhi integer.

1042
00:46:20,952 --> 00:46:23,660
Na hapa ni kwamba, je, wakati kujenga,
na hii ni kwa nini ni muhimu.

1043
00:46:23,660 --> 00:46:26,700
Halisi kufanya hivyo,
wakati n ni chini ya 1.

1044
00:46:26,700 --> 00:46:28,030
Basi hebu angalia nini kinatokea.

1045
00:46:28,030 --> 00:46:30,760
Mimi magazeti nje, tafadhali
nipe chanya int.

1046
00:46:30,760 --> 00:46:34,300
Mimi kisha kupata int, kwa kutumia CS50
kazi na kuhifadhiwa katika n.

1047
00:46:34,300 --> 00:46:38,990
>> Na kisha, nini mstari wa kanuni pengine
anapata kunyongwa ijayo, mantiki?

1048
00:46:38,990 --> 00:46:41,890
Ambayo mstari namba?

1049
00:46:41,890 --> 00:46:42,571
Yeah, hivyo 31.

1050
00:46:42,571 --> 00:46:45,320
Bila kujua hii mpaka wameweza
wameambiwa au aina ya kudai jambo hilo,

1051
00:46:45,320 --> 00:46:45,986
lakini hiyo ni kweli.

1052
00:46:45,986 --> 00:46:48,280
Ni inakwenda juu hadi chini
na kisha anaendelea kurudia.

1053
00:46:48,280 --> 00:46:55,840
Hivyo kama mimi typed katika kusema, idadi
hasi 1, ni n chini ya hasi 1?

1054
00:46:55,840 --> 00:46:56,340
Naam.

1055
00:46:56,340 --> 00:46:58,470
Kwa sababu hasi 1 ni chini ya 1.

1056
00:46:58,470 --> 00:46:59,510
Hivyo kile lazima kutokea?

1057
00:46:59,510 --> 00:47:03,260
Mimi nina kwenda kufanya hivi
wakati n ni chini ya 1,

1058
00:47:03,260 --> 00:47:05,760
hivyo mimi nina kwenda nyuma ya mstari 28.

1059
00:47:05,760 --> 00:47:09,530
>> Na kila time-- na hebu kukimbia Haya
kufanya kazi kwa 1 kukusanya ni,

1060
00:47:09,530 --> 00:47:11,340
na sasa dot slash kazi 1.

1061
00:47:11,340 --> 00:47:14,280
Kama mimi aina hasi 1, ni
kwenda kuweka yelling saa yangu

1062
00:47:14,280 --> 00:47:17,530
mpaka mimi kushirikiana kwa sababu kila
wa pembejeo yangu ni chini ya 1

1063
00:47:17,530 --> 00:47:20,070
na kama ni wakati chini ya 1,
Mimi nina kwenda kuendelea kufanya hivyo.

1064
00:47:20,070 --> 00:47:24,240
Kama mimi hatimaye kuwapa idadi kama 50,
nashiriki, inasema, shukrani kwa ajili ya 50.

1065
00:47:24,240 --> 00:47:24,970
Kwa nini?

1066
00:47:24,970 --> 00:47:30,640
Kwa sababu kwa haraka kama n ni si chini ya
1, mimi kuacha kupata kukwama katika kitanzi hii,

1067
00:47:30,640 --> 00:47:33,840
na keyword hii mpya leo,
Kwa upande wake, literally anafanya hivyo.

1068
00:47:33,840 --> 00:47:36,800
Hivyo nimekuwa tu kutekelezwa, katika
maana, sawa na GetString,

1069
00:47:36,800 --> 00:47:40,590
ambapo mimi nina kuwapatia nyuma
mwenye kutumia yangu, baadhi ya thamani.

1070
00:47:40,590 --> 00:47:42,820
Haina kuwa
kamba, ni int.

1071
00:47:42,820 --> 00:47:44,990
Hivyo rahisi, haraka
mfano, lakini tutaweza karibuni

1072
00:47:44,990 --> 00:47:47,930
kuona baadhi ya kisasa zaidi
matoleo bado.

1073
00:47:47,930 --> 00:47:53,882
Kwa kweli, hebu tuangalie
numeric moja, iitwayo return.c.

1074
00:47:53,882 --> 00:47:55,590
Na hii moja kweli
kidogo rahisi.

1075
00:47:55,590 --> 00:47:59,010
Hivyo madhumuni ya mpango huu katika
life-- hebu kukusanya na kukimbia nayo,

1076
00:47:59,010 --> 00:48:03,090
hivyo kufanya kurudi, dot
kufyeka, return-- taarifa

1077
00:48:03,090 --> 00:48:05,530
Mpango tu cubes thamani 2.

1078
00:48:05,530 --> 00:48:08,410
Ni pretty kijinga, ni vigumu
kanuni, haina kuchukua pembejeo yoyote,

1079
00:48:08,410 --> 00:48:12,220
lakini haina kuonyesha mwingine
kazi ambayo nimekuwa imeandikwa mwenyewe.

1080
00:48:12,220 --> 00:48:15,760
Hivyo hapa, nimekuwa alitangaza
kutofautiana, iitwayo x, ya aina int,

1081
00:48:15,760 --> 00:48:17,840
sawa na idadi 2,
kabisa holela.

1082
00:48:17,840 --> 00:48:19,530
Hii ni baadhi tu ya uchapishaji fluffy.

1083
00:48:19,530 --> 00:48:23,070
Inasema x ni sasa, kama na
vile, cubing nukta nukta nukta.

1084
00:48:23,070 --> 00:48:26,390
Na uchawi ni dhahiri katika mstari 21.

1085
00:48:26,390 --> 00:48:30,120
Mimi nina wito kazi kuitwa, mchemraba,
Mimi kuikabidhi karatasi

1086
00:48:30,120 --> 00:48:32,890
kwa idadi 2 yameandikwa juu yake,
na kile thamani, hesabu,

1087
00:48:32,890 --> 00:48:34,860
Je, mimi wanataka kupata nje ya hayo?

1088
00:48:34,860 --> 00:48:36,570
Kama vile sanity hundi?

1089
00:48:36,570 --> 00:48:37,070
8.

1090
00:48:37,070 --> 00:48:37,570
Sawa?

1091
00:48:37,570 --> 00:48:40,160
Mimi nataka 2 cubed nyuma, 2 kwa
nguvu ya 3, hivyo 8 nyuma.

1092
00:48:40,160 --> 00:48:42,570
>> Hivyo ambapo ni mchemraba kutekelezwa?

1093
00:48:42,570 --> 00:48:44,349
Naam, ilani ni kutekelezwa chini hapa.

1094
00:48:44,349 --> 00:48:47,140
Na kama kabla, kifikra,
hata kama syntax pengine ni

1095
00:48:47,140 --> 00:48:49,320
mpya sana kwa wengi wenu,
Nataka kazi hii

1096
00:48:49,320 --> 00:48:51,780
mkono yangu nyuma karatasi ya
karatasi na int juu yake.

1097
00:48:51,780 --> 00:48:53,990
Hivyo nina int,
jina ni kiholela,

1098
00:48:53,990 --> 00:48:55,530
lakini kwa urahisi aitwaye mchemraba.

1099
00:48:55,530 --> 00:48:58,430
Pembejeo kwa hiyo, ni n ya
aina integer, hivyo hiyo ni

1100
00:48:58,430 --> 00:49:00,800
jinsi siwezi kupita katika idadi
2 katika karatasi.

1101
00:49:00,800 --> 00:49:03,910
Na kisha zinageuka C inasaidia
hisabati, hivyo huna x kwa mara,

1102
00:49:03,910 --> 00:49:06,680
wewe tu kutumia asteriski
kwa kuzidisha.

1103
00:49:06,680 --> 00:49:11,070
Na hii anarudi mara n n mara
n, ambayo ni tu thamani cubed.

1104
00:49:11,070 --> 00:49:12,840
>> Hivyo ambapo ni sisi kwenda kwa yote haya?

1105
00:49:12,840 --> 00:49:14,570
Hii ni dhahiri
ziara ya kimbunga, wengine uhakika,

1106
00:49:14,570 --> 00:49:16,410
kwamba katika sehemu super
na katika tatizo kuweka 1,

1107
00:49:16,410 --> 00:49:18,368
wewe utakuwa kutembea kwa njia ya
yote haya ni mengi mno.

1108
00:49:18,368 --> 00:49:22,490
Na katika tatizo kuweka 1, tutaweza mpito
kutoka dunia graphical ya Scratch

1109
00:49:22,490 --> 00:49:25,640
na kitu zaidi ya mstari amri
katika C. Lakini tutaweza kuteka msukumo

1110
00:49:25,640 --> 00:49:27,680
kutoka mchezo huu hapa
kutoka yesteryear, eti

1111
00:49:27,680 --> 00:49:31,591
kutumia C na toleo la kawaida la
p kuweka wewe utakuwa kutekeleza Mario ya piramidi.

1112
00:49:31,591 --> 00:49:34,340
Na katika toleo hacker ya
p kuweka, kama hivyo kuchagua kumchagua,

1113
00:49:34,340 --> 00:49:38,280
utakuwa kutekeleza kidogo zaidi
changamoto piramidi na peaks mbili.

1114
00:49:38,280 --> 00:49:41,239
Itabidi pia kutekeleza
algorithm, algorithm tamaa.

1115
00:49:41,239 --> 00:49:43,030
Ni zinageuka kuna ya
baadhi mantiki ya kuvutia

1116
00:49:43,030 --> 00:49:45,640
nyuma ya mchakato wa
mbio Kituo cha cashier ya

1117
00:49:45,640 --> 00:49:47,410
na kwa kweli kuwapatia
mtu mabadiliko nyuma.

1118
00:49:47,410 --> 00:49:50,410
Kuna algorithm hiyo ni haki
moja kwa moja, kwamba waweza hata

1119
00:49:50,410 --> 00:49:53,576
kufahamu shirikishi wakati wa kwanza kusoma
it-- kutambua kwamba kile nimekuwa daima

1120
00:49:53,576 --> 00:49:57,110
amefanya wakati wowote Nimekupa mtu baadhi
fedha back-- kwamba utapata daima

1121
00:49:57,110 --> 00:50:00,679
kupunguza idadi ya
maelezo karatasi au chuma sarafu

1122
00:50:00,679 --> 00:50:02,220
kuwa wewe ni kuwapatia nyuma kwa mtumiaji.

1123
00:50:02,220 --> 00:50:04,610
Na hii, bila shaka, ni kulazimisha
kwa sababu kama wewe kwenda CVS au whatnot,

1124
00:50:04,610 --> 00:50:06,430
hawataki kuwa mitupu
rundo zima la watoto

1125
00:50:06,430 --> 00:50:07,596
au kundi zima la pennies.

1126
00:50:07,596 --> 00:50:10,120
Unataka fewest
sarafu, pengine, iwezekanavyo.

1127
00:50:10,120 --> 00:50:13,070
>> Hatimaye, utapata pia kuwa changamoto
dabble katika ulimwengu wa maji

1128
00:50:13,070 --> 00:50:17,220
na kweli kupata shukrani
kwa ramani kati ya viwango vya kati yake,

1129
00:50:17,220 --> 00:50:19,890
ya kama, maji katika oga,
ni kiasi gani maji ni kutumika.

1130
00:50:19,890 --> 00:50:22,640
Na dokezo humo,
itakuwa kipande cha hii hapa,

1131
00:50:22,640 --> 00:50:24,840
ambayo tutaweza kuishia juu ya kwa
sekunde 60 tu, kwamba

1132
00:50:24,840 --> 00:50:29,070
inajenga picha ya
chini kati yake oga vichwa.

1133
00:50:29,070 --> 00:50:30,886
>> [VIDEO avspelning]

1134
00:50:30,886 --> 00:50:31,385
-All Haki.

1135
00:50:31,385 --> 00:50:32,774
I got kila kitu hapa.

1136
00:50:32,774 --> 00:50:35,800
I got Kimbunga F Series,
Hydra, Jetflow, Stockholms

1137
00:50:35,800 --> 00:50:37,660
Supersteam, wewe jina hilo.

1138
00:50:37,660 --> 00:50:39,265
>> -Na Je, wewe kupendekeza?

1139
00:50:39,265 --> 00:50:40,460
>> -Nini Ni wewe kuangalia kwa?

1140
00:50:40,460 --> 00:50:41,300
>> -Power Mtu.

1141
00:50:41,300 --> 00:50:42,285
Madaraka.

1142
00:50:42,285 --> 00:50:42,910
-kama Silkwood.

1143
00:50:42,910 --> 00:50:44,520
-yaani Ni kwa mionzi.

1144
00:50:44,520 --> 00:50:46,335
-yaani Ni haki.

1145
00:50:46,335 --> 00:50:48,275
-Sasa Ni kitu gani?

1146
00:50:48,275 --> 00:50:49,704
-yaani Ni commando 450.

1147
00:50:49,704 --> 00:50:50,620
Siuzi kwamba moja.

1148
00:50:50,620 --> 00:50:51,700
>> -Lakini Kwamba ni nini tunataka.

1149
00:50:51,700 --> 00:50:52,680
Ni kikomandoo 450.

1150
00:50:52,680 --> 00:50:53,882
>> -Hakuna Amini kwangu.

1151
00:50:53,882 --> 00:50:55,090
Ni tu kutumika katika circus.

1152
00:50:55,090 --> 00:50:56,512
Ni kwa tembo.

1153
00:50:56,512 --> 00:50:59,356
>> -I'll Kulipa chochote.

1154
00:50:59,356 --> 00:51:01,252
>> -Nini Kuhusu Jerry?

1155
00:51:01,252 --> 00:51:02,760
>> Hapo hakuweza kushughulikia jambo hilo.

1156
00:51:02,760 --> 00:51:04,910
Yeye ni tete.

1157
00:51:04,910 --> 00:51:05,750
Oh yeah.

1158
00:51:05,750 --> 00:51:36,737

1159
00:51:36,737 --> 00:51:37,320
[Mwisho avspelning]

1160
00:51:37,320 --> 00:51:37,700
DAVID J Malan: zote haki.

1161
00:51:37,700 --> 00:51:38,820
Hiyo ni kama kwa CS50.

1162
00:51:38,820 --> 00:51:40,050
Tutaweza kuona wewe wiki ijayo.

1163
00:51:40,050 --> 00:51:45,910

1164
00:51:45,910 --> 00:51:49,029
>> SPIKA 1: [? Scully?], [? Ian,?]
mbali kama mradi huu Outro,

1165
00:51:49,029 --> 00:51:50,362
una nini guys kuja na?

1166
00:51:50,362 --> 00:51:51,990
>> SPIKA 2: Naam, tumekuwa aliyopewa
ni aina ya mawazo,

1167
00:51:51,990 --> 00:51:53,250
na tunadhani kwamba njia bora to--

1168
00:51:53,250 --> 00:51:53,660
>> SPIKA 3: Mei mimi?

1169
00:51:53,660 --> 00:51:54,326
>> SPIKA 2: Naam.

1170
00:51:54,326 --> 00:51:56,360
Kwa njia zote, kwa kweli.

1171
00:51:56,360 --> 00:51:59,425
>> SPIKA 3: Hivyo nadhani
tunaweza kuhitimisha wazo yetu

1172
00:51:59,425 --> 00:52:05,450
kwa outros kwa moja word-- chochote.

1173
00:52:05,450 --> 00:52:08,950

1174
00:52:08,950 --> 00:52:10,409
>> DAVID J Malan: Hakuna?

1175
00:52:10,409 --> 00:52:11,200
SPIKA 3: Kitu.

1176
00:52:11,200 --> 00:52:12,990
DAVID J Malan: Hiyo ina maana gani?

1177
00:52:12,990 --> 00:52:16,260
SPIKA 3: outros ni kuhusu chochote.

1178
00:52:16,260 --> 00:52:21,720
SPIKA 2: Naam, I mean, katika falsafa,
I mean, hakuna kitu ni daima kitu.

1179
00:52:21,720 --> 00:52:24,200
SPIKA 1: Hivyo what's--
nini dhana?

1180
00:52:24,200 --> 00:52:25,720
SPIKA 3: Hivyo ni kama maisha.

1181
00:52:25,720 --> 00:52:26,680
Sawa.

1182
00:52:26,680 --> 00:52:28,294
Mlifanya nini leo?

1183
00:52:28,294 --> 00:52:31,811
>> DAVID J Malan: Mimi aliamka, alikuwa
kifungua kinywa, na alikuja kufanya kazi.

1184
00:52:31,811 --> 00:52:34,056
>> SPIKA 3: Hiyo ni OUTRO.

1185
00:52:34,056 --> 00:52:36,806
SPIKA 2: Lakini, I mean, hawapaswi
kitu kutokea kwake juu ya the--

1186
00:52:36,806 --> 00:52:37,889
SPIKA 3: Hapana, hapana, hapana, hapana.

1187
00:52:37,889 --> 00:52:40,220
Hakuna kinachotokea.

1188
00:52:40,220 --> 00:52:42,910
>> SPIKA 1: Hivyo kwa nini sisi kuangalia?

1189
00:52:42,910 --> 00:52:46,956
>> SPIKA 3: Kwa sababu
ni OUTRO kwa CS50.

1190
00:52:46,956 --> 00:52:48,652
>> DAVID J Malan: Bado.

1191
00:52:48,652 --> 00:52:49,151