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[Music kucheza]

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>> DOUG LLOYD: OK hivyo pendekezo
kabla ya kuanza hapa.

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Kama si watched video juu ya
kuyatumia unaweza kutaka kufanya hivyo kwanza.

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Kwa sababu video hii ni mwingine
njia ya kufanya kazi na kuyatumia.

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>> Hivyo ni kwenda kuzungumza
kuhusu baadhi ya dhana

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kwamba sisi cover katika
kuyatumia video, na tuko

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kwenda Gloss juu yao sasa,
kuchukua kwamba wao uko tayari

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aina ya kueleweka.

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Hivyo hiyo ni onyo tu yako ya haki
kwamba kama wewe ni kuona video hii

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na hawajaona
kuyatumia video, inaweza aina ya

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kuruka juu ya kichwa yako kidogo.

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Na hivyo inaweza kuwa bora
kuangalia ni ili.

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>> Hivyo tumeona moja
njia ya kufanya kazi na kuyatumia,

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ambayo ni sisi kutangaza
kutofautiana, na kisha sisi

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kutangaza mwingine kutofautiana, pointer
kutofautiana, kwamba pointi kwa hilo.

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Hivyo tumeunda
kutofautiana kwa jina, tumekuwa

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umba kutofautiana pili kwa jina,
na sisi uhakika kwamba kutofautiana pili

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wakati huo wa kwanza.

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Hii ina aina ya
Tatizo ingawa, kwa sababu

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inahitaji sisi kujua hasa
ni kiasi gani kumbukumbu tuko

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kwenda haja sasa
mpango wetu ni ulioandaliwa.

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>> Kwanini hivyo?

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Kwa sababu tunahitaji kuwa na uwezo wa kutaja au
kutambua yote ya vigezo iwezekanavyo

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sisi kukutana.

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Tupate kuwa na safu hiyo inaweza kuwa ni
uwezo wa kushikilia mengi ya habari,

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lakini bado si
hasa sahihi kutosha.

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Nini kama hatujui,
nini kama hatuna wazo

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kiasi gani tutaweza haja wakati kukusanya?

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Au nini kama mpango wetu mapenzi
kukimbia kwa kweli kwa muda mrefu,

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kukubali mtumiaji mbalimbali
data, na hatuwezi kwa kweli

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makisio kama tuko
kwenda haja vitengo 1,000?

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>> Siyo kama tunaweza
kusema katika mstari amri

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kuingia vitu ngapi
unafikiri itabidi.

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Naam nini kama kwamba nadhani ni sahihi?

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Mgao wa nguvu kumbukumbu
aina ya inaruhusu sisi njia

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kupata kote na tatizo hili fulani.

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Na njia ni gani
ni kwa kutumia kuyatumia.

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>> Tunaweza kutumia kuyatumia kwa
kupata dynamically

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zilizotengwa kumbukumbu, kumbukumbu kwamba ni
zilizotengwa kama mpango wako ni mbio.

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Siyo zilizotengwa wakati kukusanya.

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Wakati dynamically kutenga
kumbukumbu inatoka pool

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ya kumbukumbu inayojulikana kama chungu.

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Hapo awali zote kumbukumbu tumekuwa
ikifanya kazi na katika kozi

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imekuwa kuja kutoka bwawa
ya kumbukumbu inayojulikana kama stack.

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Njia nzuri ya ujumla
kuweka katika utawala mind-- na hii

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daima haina kushikilia kweli,
lakini pretty much karibu

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daima ana true-- ni kwamba yoyote
wakati unaweza kumpa jina kutofautiana ni

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pengine anaishi juu ya stack.

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Na wakati wowote huna
kutoa kutofautiana jina,

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ambayo unaweza kufanya na kumbukumbu ya nguvu
mgao, ni anaishi kwenye lundo.

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>> Sasa mimi nina aina ya kuwasilisha hii kama
kama kuna mabwawa haya mawili ya kumbukumbu.

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Lakini unaweza tumeona hii
mchoro, ambayo kwa ujumla ni

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uwakilishi wa
nini kumbukumbu inaonekana kama,

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na sisi siyo kwenda kwa huduma ya juu zote
mambo kwa juu na chini.

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Nini sisi huduma ya juu ni sehemu huu katika
katikati hapa, chungu na stack.

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Kama unaweza kuona na
kuangalia mchoro huu,

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hizi kweli si wawili
mabwawa tofauti ya kumbukumbu.

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Ni moja ya pamoja bwawa la kumbukumbu
ambapo kuanza, katika hii Visual

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kuanza chini
na kuanza kujaza juu

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kuanzia chini kwa stack, na wewe
kuanza juu na kuanza kujaza juu

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kutoka juu kwenda chini na lundo.

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Lakini kwa kweli ni
sawa pool, ni tu

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matangazo mbalimbali, maeneo mbalimbali
katika kumbukumbu kuwa ni kuwa zilizotengwa.

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Na unaweza kukimbia nje ya
kumbukumbu kwa aidha kuwa

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lundo kwenda njia yote
hadi chini, au kuwa na

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stack kwenda njia yote ya juu,
au kuwa na lundo na stack

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kukutana dhidi ya kila mmoja.

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Wote wa wale inaweza kuwa masharti
vinavyosababisha mpango wako

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kukimbia nje ya kumbukumbu.

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Hivyo kuendelea kuwa katika akili.

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Tunapozungumzia kuhusu
lundo na stack

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sisi ni kweli kuzungumza juu ya
sawa mkuu chunk ya kumbukumbu, tu

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sehemu mbalimbali za kumbukumbu hiyo.

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>> Hivyo ni jinsi gani sisi kupata dynamically
kumbukumbu zilizotengwa katika nafasi ya kwanza?

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Ni kwa jinsi gani mpango wetu kupata
kumbukumbu kama ni mbio?

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Naam C hutoa kazi kuitwa
malloc, kumbukumbu allocator, ambayo

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wewe kufanya wito kwa, na wewe kupita katika
jinsi ka ya kumbukumbu kwamba unataka mingi.

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Hivyo kama mpango wako ni mbio
na unataka integer Runtime,

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unaweza mallock ka nne ya
, malloc kumbukumbu mabano nne.

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>> mallock watapitia
kutafuta njia chungu,

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kwa sababu tuko dynamically
kugawa kumbukumbu,

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na itakuwa kurudi wewe
pointer kwamba kumbukumbu.

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Haina kukupa kwamba memory--
haina kuwapa jina,

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inakupa pointer yake.

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Na hivyo ndiyo sababu tena nikasema
kuwa ni muhimu labda

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waliangalia kuyatumia video
kabla ya sisi kupata mbali mno katika hili.

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Hivyo malloc kinaendelea
kukupa nyuma pointer.

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>> Kama mallock hawezi kukupa yoyote
kumbukumbu kwa sababu umefanya kukimbia nje,

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kutakuwa na kukupa nyuma pointer null.

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Je, unakumbuka kile kinachotokea kama sisi
kujaribu dereference na pointer null?

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Sisi kuteseka seg kosa, sawa?

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Kwamba pengine si mzuri.

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>> Hivyo kila wakati kufanya wito
malloc wewe daima, daima

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haja ya kuangalia kama au
pointer lilitoa wewe nyuma ni null.

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Kama ni, unahitaji kumaliza mpango wako
kwa sababu kama wewe kujaribu dereference na

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pointer null wewe ni kwenda
kuteseka segmentation kosa

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na mpango wako ni
kwenda kwa ajali anyway.

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Hivyo ni jinsi gani sisi statically
kupata integer?

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>> int x.

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Tumekuwa pengine amefanya hivyo
rundo la nyakati, sawa?

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Hii inajenga kutofautiana kuitwa
x kwamba anaishi juu ya stack.

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Je, sisi dynamically kupata integer?

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Int nyota px sawa na malloc 4.

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>> Au zaidi ipasavyo
tunatarajia kusema int nyota px

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sawa malloc ukubwa wa int,
tu kutupa baadhi wachache

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idadi uchawi kuzunguka mpango wetu.

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Hii ni kwenda kupata kwa ajili yetu
ka nne ya kumbukumbu kutoka lundo,

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na pointer tunapata
nyuma ni kuitwa px.

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Na kisha tu kama tumekuwa
tokea hapo sisi

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Unaweza dereference px kwa
kupata kwamba kumbukumbu.

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Jinsi gani sisi kupata integer kutoka kwa mtumiaji?

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Tunaweza kusema int x sawa kupata int.

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Hiyo ni pretty moja kwa moja.

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Nini kama tunataka kujenga safu
ya x ikifungwa kwamba kuishi katika stack?

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kuelea stack_array-- hiyo ni jina
ya yetu array-- mabano mraba x.

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Ambayo kujenga kwa ajili yetu safu
ya x ikifungwa wanaoishi juu ya stack.

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Tunaweza kujenga safu ya ikifungwa
kwamba anaishi juu ya lundo, pia.

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Syntax ili kuangalia
zaidi kidogo mbaya,

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lakini tunaweza kusema kuelea
nyota heap_array sawa na

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malloc x mara ukubwa wa kuelea.

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Nahitaji nafasi ya kutosha kushikilia
x yaliyo maadili uhakika.

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Hivyo kusema nahitaji 100
ikifungwa, au ikifungwa 1,000.

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Hivyo katika kesi kwamba itakuwa
400 ka kwa 100 ikifungwa,

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au 4,000 ka kwa ikifungwa 1000,
kwa sababu kila kuelea unachukua

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ka nne wa nafasi.

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>> Baada ya kufanya hivyo naweza kutumia
Mabano ya mraba syntax juu ya heap_array.

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Kama tu napenda juu ya stack_array, mimi
Unaweza kupata mambo yake binafsi

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kutumia heap_array sifuri, heap_array moja.

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Lakini kukumbuka sababu tunaweza kufanya hivyo
ni kwa sababu jina la safu katika C

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ni kweli pointer
kwamba safu ya kwanza kipengele.

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Hivyo ukweli kwamba sisi ni kutangaza
safu ya ikifungwa juu ya stack hapa

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ni kweli kidogo kupotosha.

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Sisi kwa kweli ni katika
mstari wa pili wa kanuni huko

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pia kujenga pointer chunk ya
kumbukumbu kwamba sisi kisha kufanya baadhi ya kazi kwa.

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>> Hapa ni tatizo kubwa na
dynamically zilizotengwa kumbukumbu ingawa,

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na hii ni kwa nini ni kweli
muhimu kuendeleza baadhi tabia nzuri

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wakati wewe ni kazi kwa hayo.

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Tofauti na statically alitangaza
kumbukumbu, kumbukumbu yako

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si moja kwa moja alirudi
mfumo wakati kazi yako ni kosa.

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Hivyo kama tuna kuu, na
kuu wito kazi

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f, f wakati finishes chochote ni kufanya
na anarudi udhibiti wa mpango

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nyuma kuu, yote ya kumbukumbu
kwamba f kutumika anapewa nyuma.

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Ni inaweza kutumika tena
na baadhi ya mpango mengine,

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au baadhi ya kazi nyingine ambazo
anapata kuitwa baadaye katika kuu.

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Inaweza kutumia kwamba kumbukumbu hiyo tena.

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>> Kama dynamically
kutenga kumbukumbu ingawa

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una kupanga kuwaambia
mfumo kuwa wewe ni kosa kwa hayo.

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Kutakuwa na kushikilia kwenye hiyo kwa ajili yenu, ambayo inaweza
kusababisha tatizo la wewe unapita

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wa kumbukumbu.

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Na kwa kweli sisi wakati mwingine kutaja
kwa hili kama kumbukumbu kuvuja.

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Na wakati mwingine uvujaji hizi kumbukumbu
kweli anaweza kweli makubwa

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kwa mfumo wa utendaji.

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>> Kama wewe ni mara kwa mara biashara ya mtumiaji
unaweza kutumia baadhi ya browsers mtandao,

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na mimi si jina majina hapa, lakini
kuna baadhi ya browsers mtandao huko nje

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kuwa ni sifa mbaya kwa kweli kuwa
uvujaji kumbukumbu ambazo si kupata fasta.

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Na kama wewe kuondoka browser yako wazi
kwa kipindi cha muda mrefu sana, siku

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na siku, au wiki, wakati mwingine
taarifa kwamba mfumo wako

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ni mbio kweli, kweli polepole.

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Na sababu ya kuwa ni kwamba
kisakuzi imetenga kumbukumbu,

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lakini kisha si aliiambia mfumo
kuwa ni kosa kwa hayo.

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Na hivyo kwamba majani chini ya kumbukumbu
inapatikana kwa wote wa programu yako mengine

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kuwa na kushiriki, kwa sababu wewe ni
leaking-- kwamba kivinjari

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mpango ni kinachovuja kumbukumbu.

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Je, sisi kutoa kumbukumbu nyuma
wakati sisi ni kosa kwa hayo?

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Vizuri kwa bahati nzuri ni
njia rahisi sana ya kufanya hivyo.

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Sisi tu bure hilo.

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Kuna kazi kuitwa bure,
anapokea pointer kumbukumbu,

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na sisi ni vizuri kwenda.

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>> Basi hebu kusema tuko katika
katikati ya mpango wetu,

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tunataka malloc wahusika 50.

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Tunataka malloc safu ambayo yanaweza
uwezo wa kufanya wahusika 50.

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Na wakati tunapata pointer nyuma
kwamba, jina kwamba pointer ni neno.

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Sisi kufanya lolote tuko
kwenda kufanya na neno,

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na kisha wakati tuko
amefanya sisi tu huru yake.

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Na sasa sisi wamerejea wale 50
ka ya kumbukumbu nyuma na mfumo.

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Baadhi ya kazi nyingine wanaweza kuzitumia.

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Hatuna wasiwasi kuhusu mateso
kumbukumbu kuvuja kwa sababu tuna huru neno.

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Tumekuwa kupewa kumbukumbu nyuma,
hivyo sisi ni kosa kufanya kazi kwa hayo.

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Hivyo kuna tatu
sheria ya dhahabu kuwa lazima

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iwekwe akilini wakati wowote uko
dynamically kugawa kumbukumbu

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kwa malloc.

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00:08:52,990 --> 00:08:56,480
Kila block ya kumbukumbu kwamba
wewe malloc ni lazima lifunguliwe

185
00:08:56,480 --> 00:08:58,430
kabla ya mpango wako alimaliza mbio.

186
00:08:58,430 --> 00:09:02,029
Sasa tena, katika appliance au katika
IDE hii aina ya ikitokea kwa wewe anyway

187
00:09:02,029 --> 00:09:04,820
wakati you-- hii kutokea anyway
wakati mpango wako ni terminated,

188
00:09:04,820 --> 00:09:06,880
kumbukumbu zote zitatolewa.

189
00:09:06,880 --> 00:09:10,750
Lakini ni nzuri kwa ujumla coding
mazoezi kwa siku zote, wakati wewe ni kosa,

190
00:09:10,750 --> 00:09:13,810
bure yale mallocd.

191
00:09:13,810 --> 00:09:16,690
>> Alisema kwamba, mambo tu kwamba
wameweza mallocd inapaswa kuwa huru.

192
00:09:16,690 --> 00:09:19,880
Kama statically kutangaza
integer, int x nusu ya matumbo,

193
00:09:19,880 --> 00:09:23,500
kwamba anaishi juu ya stack, wewe
si basi wanataka bure x.

194
00:09:23,500 --> 00:09:25,970
Mambo tu kwamba wameweza
mallocd inapaswa kuwa huru.

195
00:09:25,970 --> 00:09:28,960
>> Na Mwisho, hawana bure kitu mara mbili.

196
00:09:28,960 --> 00:09:31,170
Ambayo inaweza kusababisha
hali nyingine weird.

197
00:09:31,170 --> 00:09:33,530
Hivyo kila kitu ambacho umefanya
mallocd ina kuwa huru.

198
00:09:33,530 --> 00:09:36,000
Mambo tu kwamba wameweza
malloc inapaswa kuwa huru.

199
00:09:36,000 --> 00:09:38,730
Na hawana bure kitu mara mbili.

200
00:09:38,730 --> 00:09:43,660
>> Basi hebu kwenda kupitia mfano hapa
kile baadhi dynamically zilizotengwa

201
00:09:43,660 --> 00:09:46,122
kumbukumbu ili kuangalia kama mchanganyiko
na baadhi ya kumbukumbu tuli.

202
00:09:46,122 --> 00:09:47,080
Nini kinaweza kutokea hapa?

203
00:09:47,080 --> 00:09:48,913
Kuona kama unaweza kufuata
pamoja na nadhani nini

204
00:09:48,913 --> 00:09:51,720
kinaenda kutokea kama sisi kwenda
kupitia mistari haya yote ya kificho.

205
00:09:51,720 --> 00:09:53,980
>> Hivyo tunasema int m.

206
00:09:53,980 --> 00:09:54,840
Nini kinatokea hapa?

207
00:09:54,840 --> 00:09:56,339
Naam hii ni pretty moja kwa moja.

208
00:09:56,339 --> 00:09:59,650
Mimi kuunda integer variable kuitwa m.

209
00:09:59,650 --> 00:10:01,400
Mimi rangi yake ya kijani,
kwa sababu hiyo ni rangi

210
00:10:01,400 --> 00:10:03,730
kwamba mimi kutumia wakati mimi kuzungumza
kuhusu integer vigezo.

211
00:10:03,730 --> 00:10:05,160
Ni eneo la hatari.

212
00:10:05,160 --> 00:10:08,400
Ni wito m, na unaweza
kuhifadhi integers ndani yake.

213
00:10:08,400 --> 00:10:12,400
>> Nini kama mimi kisha kusema int nyota?

214
00:10:12,400 --> 00:10:13,530
Vizuri kwamba ni pretty sawa.

215
00:10:13,530 --> 00:10:15,780
Mimi kujenga sanduku aitwaye.

216
00:10:15,780 --> 00:10:19,100
Ni uwezo wa kufanya int
nyota, kuyatumia kwa integers.

217
00:10:19,100 --> 00:10:21,570
Hivyo mimi nina kuipaka rangi ya kijani-ish pia.

218
00:10:21,570 --> 00:10:24,140
>> Najua ina kitu
cha kufanya na integer,

219
00:10:24,140 --> 00:10:25,852
lakini siyo yenyewe integer.

220
00:10:25,852 --> 00:10:27,310
Lakini wazo moja kiasi pretty.

221
00:10:27,310 --> 00:10:28,101
Nimekuwa kuundwa eneo la hatari.

222
00:10:28,101 --> 00:10:30,070
Wote hawa haki
sasa wanaishi juu ya stack.

223
00:10:30,070 --> 00:10:32,520
Nimekuwa amewapa majina yote mawili.

224
00:10:32,520 --> 00:10:36,750
>> int nyota b sawa na malloc ukubwa wa int.

225
00:10:36,750 --> 00:10:38,560
Hii moja inaweza kuwa ni kidogo suala gumu.

226
00:10:38,560 --> 00:10:44,110
Kuchukua pili na kufikiri juu ya nini
bila kutarajia kutokea kwenye mchoro huu.

227
00:10:44,110 --> 00:10:50,210
int nyota b sawa na malloc ukubwa wa int.

228
00:10:50,210 --> 00:10:51,940
>> Naam hii haina tu kujenga sanduku moja.

229
00:10:51,940 --> 00:10:53,800
Hii kweli inajenga masanduku mawili.

230
00:10:53,800 --> 00:10:58,670
Na mahusiano, pia itaanzisha
hatua katika uhusiano.

231
00:10:58,670 --> 00:11:02,240
Tumekuwa zilizotengwa kuzuia moja
ya kumbukumbu juu ya lundo.

232
00:11:02,240 --> 00:11:05,940
Taarifa kwamba juu sanduku sahihi
kuna hana jina.

233
00:11:05,940 --> 00:11:06,760
>> Sisi mallocd yake.

234
00:11:06,760 --> 00:11:08,050
Ipo juu ya lundo.

235
00:11:08,050 --> 00:11:10,090
Lakini b ina jina.

236
00:11:10,090 --> 00:11:11,950
Ni pointer kutofautiana kuitwa b.

237
00:11:11,950 --> 00:11:13,910
Kwamba anaishi juu ya stack.

238
00:11:13,910 --> 00:11:18,250
>> Hivyo ni kipande cha kumbukumbu
kwamba pointi kwa mtu mwingine.

239
00:11:18,250 --> 00:11:21,840
b ina anuani
ya kwamba block ya kumbukumbu.

240
00:11:21,840 --> 00:11:23,757
Haina jina vinginevyo.

241
00:11:23,757 --> 00:11:24,590
Lakini inaelekeza katika hilo.

242
00:11:24,590 --> 00:11:29,760
Hivyo wakati sisi kusema int nyota b sawa na
malloc ukubwa wa int, kwamba haki pale,

243
00:11:29,760 --> 00:11:33,490
kwamba mshale kwamba popped up juu ya
upande wa kulia huko, jambo ambalo kwa ujumla,

244
00:11:33,490 --> 00:11:36,740
Mimi itabidi hivyo kuonekana
tena, ni nini kinatokea.

245
00:11:36,740 --> 00:11:39,341
Yote hayo hufanyika katika
kwamba line moja ya kanuni.

246
00:11:39,341 --> 00:11:41,340
Sasa tutaweza kupata zaidi kidogo
moja kwa moja tena.

247
00:11:41,340 --> 00:11:43,330
a sawa na ampersand m.

248
00:11:43,330 --> 00:11:46,280
Je, unakumbuka kile
sawa ampersand m ni?

249
00:11:46,280 --> 00:11:48,920
Naam hiyo ndiyo anapata m ya mahali.

250
00:11:48,920 --> 00:11:54,150
Au kuweka zaidi diagrammatically,
pointi kwa m.

251
00:11:54,150 --> 00:11:56,360
>> a sawa na b.

252
00:11:56,360 --> 00:11:57,560
OK hivyo hapa ni mtu mwingine.

253
00:11:57,560 --> 00:11:59,230
A sawa na b.

254
00:11:59,230 --> 00:12:02,260
Nini kitatokea
kwa mchoro wakati huu?

255
00:12:02,260 --> 00:12:04,330
>> Vizuri kukumbuka kuwa
matendo operator zoezi

256
00:12:04,330 --> 00:12:08,960
na kumshirikisha thamani ya
Haki ya thamani upande wa kushoto.

257
00:12:08,960 --> 00:12:14,820
Hivyo badala ya akizungumzia m, sasa
anazungumzia sehemu moja kwamba pointi b.

258
00:12:14,820 --> 00:12:18,900
a hana uhakika na b,
anasema pointi ambapo b.

259
00:12:18,900 --> 00:12:25,280
>> Kama alisema b kwamba ingekuwa
wamekuwa sawa na ampersand b.

260
00:12:25,280 --> 00:12:28,150
Lakini badala sawa na b tu
ina maana kwamba na b ni sasa

261
00:12:28,150 --> 00:12:31,770
akizungumzia anuani hiyo, kwa sababu
ndani ya b ni mahali.

262
00:12:31,770 --> 00:12:35,004
Na sasa ndani ya ni anuani hiyo.

263
00:12:35,004 --> 00:12:37,170
m ni sawa na 10, pengine
zaidi jambo moja kwa moja

264
00:12:37,170 --> 00:12:38,690
tumefanya katika kidogo.

265
00:12:38,690 --> 00:12:40,460
Kuweka 10 katika eneo la hatari.

266
00:12:40,460 --> 00:12:45,640
Star b sawa na m pamoja na 2, kukumbuka kutoka
wetu kuyatumia video kile nyota b maana yake.

267
00:12:45,640 --> 00:12:50,230
Tunakwenda dereference b na kuweka
baadhi thamani kwa kuwa kumbukumbu eneo.

268
00:12:50,230 --> 00:12:51,860
Katika kesi hiyo 12.

269
00:12:51,860 --> 00:12:55,300
>> Hivyo wakati sisi dereference hatua ya
kukumbuka sisi tu kusafiri chini mshale.

270
00:12:55,300 --> 00:12:58,205
Au kuweka njia nyingine, sisi
kwenda kuwa kumbukumbu anuani

271
00:12:58,205 --> 00:12:59,580
na sisi kuendesha kwa namna fulani.

272
00:12:59,580 --> 00:13:00,830
Sisi kuweka baadhi ya thamani katika huko.

273
00:13:00,830 --> 00:13:03,960
Katika kesi hii nyota b
sawa m pamoja na 2 ni tu

274
00:13:03,960 --> 00:13:08,230
kwenda kutofautiana alisema kwa b,
kwenda kumbukumbu alisema kwa b,

275
00:13:08,230 --> 00:13:11,750
na kuweka m plus 2 katika huko, 12.

276
00:13:11,750 --> 00:13:14,970
>> Sasa mimi bure b.

277
00:13:14,970 --> 00:13:16,490
Kile kinachotokea wakati mimi bure b?

278
00:13:16,490 --> 00:13:18,800
Kumbuka kile alisema njia ya bure.

279
00:13:18,800 --> 00:13:21,920
Nataka kusema nini wakati mimi bure b?

280
00:13:21,920 --> 00:13:23,410
>> Mimi kosa kufanya kazi na hayo, haki?

281
00:13:23,410 --> 00:13:25,702
Mimi kimsingi kutoa juu ya kumbukumbu.

282
00:13:25,702 --> 00:13:26,910
Mimi kuwapa nyuma na mfumo.

283
00:13:26,910 --> 00:13:33,010
Sina haja hii tena ni
nini mimi kuwaambia, sawa?

284
00:13:33,010 --> 00:13:37,390
>> Sasa kama mimi kusema nyota a
sawa 11 pengine unaweza

285
00:13:37,390 --> 00:13:40,460
tayari kuwaambia kwamba kitu mbaya
kinaenda kutokea hapa, sawa?

286
00:13:40,460 --> 00:13:44,160
Na hakika kama mimi walijaribu kuwa mimi pengine
wangepata segmentation kosa.

287
00:13:44,160 --> 00:13:47,140
Kwa sababu sasa, ingawa
awali kwamba chunk ya kumbukumbu

288
00:13:47,140 --> 00:13:50,220
ni jambo ambalo sikuwa
upatikanaji wa, katika hatua hii

289
00:13:50,220 --> 00:13:54,590
sasa mimi nina kupata kumbukumbu kwamba
si kisheria kwa ajili yangu na kupata.

290
00:13:54,590 --> 00:13:57,330
>> Na kama sisi pengine
kukumbuka, wakati sisi kupata kumbukumbu

291
00:13:57,330 --> 00:14:00,000
kwamba sisi siyo zinatakiwa kugusa,
hiyo ni sababu ya kawaida

292
00:14:00,000 --> 00:14:01,860
ya segmentation
kosa. Na hivyo mpango wangu

293
00:14:01,860 --> 00:14:05,170
ingekuwa ajali kama mimi walijaribu kufanya hii.

294
00:14:05,170 --> 00:14:09,910
Hivyo tena ni wazo nzuri ya kupata nzuri
mazoezi na nzuri tabia ingrained

295
00:14:09,910 --> 00:14:12,920
wakati wa kufanya kazi kwa malloc na bure,
hivyo kwamba huna kuteseka segmentation

296
00:14:12,920 --> 00:14:15,310
makosa, na kwamba matumizi
yako dynamically zilizotengwa

297
00:14:15,310 --> 00:14:17,370
kumbukumbu uwajibikaji.

298
00:14:17,370 --> 00:14:20,300
>> Mimi nina Doug Lloyd hii ni CS50.

299
00:14:20,300 --> 00:14:21,947