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>> [Music kucheza]

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SPIKA: zote haki.

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Basi hebu majadiliano juu ya lingine
Jambo hiyo ni aina ya pekee ya C,

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ambayo ni aina data na vigezo.

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Wakati mimi kusema kipekee kwa C, mimi kwa kweli
maana tu katika mazingira ya,

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kama tumekuwa programu
kwa kweli kwa muda mrefu,

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wameweza pengine si
kazi na aina ya data

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kama umetumia kisasa
Programu lugha.

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Lugha ya kisasa kama
PHP na JavaScript,

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ambayo tutaweza pia kuona kidogo
baadaye katika shaka,

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wewe si kweli kuwa bayana
Aina ya data ya kutofautiana

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wakati matumizi yake.

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>> Wewe tu kutangaza yake na kuanza kutumia.

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Kama ni integer, ni
kujua ni integer.

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Kama ni tabia, ni
anajua ni tabia.

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Kama ni neno, anajua
ni kamba, kinachojulikana.

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>> Lakini katika C, ambayo ni
Lugha wakubwa, tunahitaji

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bayana data
aina ya kila kutofautiana

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kuwa tunajenga mara ya kwanza
kwamba sisi kutumia kwamba kutofautiana.

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Hivyo C kuja na baadhi ya
kujengwa katika aina ya data.

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Na hebu kupata ukoo
na baadhi ya wale.

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Na kisha baadaye tutaweza pia kuzungumza
kidogo kuhusu baadhi ya aina ya data

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kwamba tumekuwa yameandikwa kwa ajili yenu,
hivyo unaweza kuzitumia katika CS50.

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>> Kwanza ni int.

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Int aina data ni kutumika kwa vigezo
ambayo kuhifadhi maadili integer.

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Hivyo 1, 2, 3, hasi 1, 2, 3, na kadhalika.

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Integers, ambayo ni kitu wewe
wanapaswa kukumbuka kwa jaribio,

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Daima kuchukua ka nne
ya kumbukumbu, ambayo ni 32 bits.

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Kuna vipande nane katika Byte.

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>> Hivyo hii ina maana kuwa idadi kubwa ya
maadili kwamba integer wanaweza kuhifadhi

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ni mdogo na kile inaweza kufaa ndani ya
32 bits thamani ya habari.

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Sasa kama ni zamu nje,
ilikuwa muda mrefu uliopita aliamua

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kwamba tunataka wameigawanya
kuwa idadi kubwa ya bits 32

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ndani ya integers hasi
na integers chanya,

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kila mmoja alipata nusu ya mbalimbali.

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Hivyo mbalimbali ya maadili kwamba sisi kuwakilisha
na integer mbalimbali kutoka hasi 2

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madarakani tarehe 31 hadi 2 kwa
nguvu 31 bala 1,

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kusababisha wewe pia haja doa kwa 0.

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>> Hivyo kimsingi nusu ya maadili iwezekanavyo
unaweza fit katika int ni hasi,

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na nusu ni mazuri.

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Na takribani hapa, hii ni kuhusu hasi
Bilioni 2 kwa kuhusu chanya bilioni 2.

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Kutoa au kuchukua wanandoa milioni mia.

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Hivyo kwamba ni nini unaweza fit
katika integer kutofautiana.

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Sasa sisi pia awe na kitu
aitwaye integer unsigned.

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Sasa ints unsigned si
tofauti aina ya kutofautiana.

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Badala yake, unsigned ni
kile kinachoitwa kufuzu.

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Ni modifies data
aina ya integer kidogo.

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>> Na katika kesi hii, ni nini unsigned
means-- na unaweza pia

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kutumia unsigned aina nyingine data,
integer si moja tu.

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Nini ufanisi gani ni mara mbili
mbalimbali chanya ya maadili

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kuwa integer wanaweza kuchukua juu ya saa
gharama ya tena kuruhusu

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wewe kuchukua maadili hasi.

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Hivyo kama una idadi ambayo unajua
kupata juu ya bilioni 2 lakini chini

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ya bilioni 4, kwa example--
ambayo ni 2 kwa 32 power--

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unaweza kutaka kutumia
int unsigned kama wewe

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kujua thamani yako kamwe kuwa hasi.

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>> Utasikia mara kwa mara na
kutumika kwa ajili ya vigezo unsigned

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katika CS50, ambayo ni kwa nini mimi kutaja hapa.

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Lakini tena, mbalimbali ya maadili kwamba
wanaweza kuwakilisha kwa integer unsigned

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kama t integer mara kwa mara, ni 0
kwa 2 hadi 32 nguvu bala 1,

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au takriban 0 na bilioni 4.

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Hivyo wameweza ufanisi mara mbili
mbalimbali chanya kwamba unaweza fit,

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lakini wameweza wamekata zote
maadili hasi.

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>> Sasa kama kando, unsigned
si tu kufuzu

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tuweze kuona kwa
data kutofautiana aina.

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Pia kuna mambo kuitwa
muda mfupi na muda na const.

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Const tutaona kidogo
kidogo baadaye katika shaka.

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Muda mfupi na muda, sisi pengine si.

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>> Lakini tu kujua kwamba kuna
ni kufuzu mengine.

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Unsigned si moja tu.

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Lakini ni moja tu tuko
kwenda kuzungumza kuhusu hivi sasa.

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Hivyo sawa.

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Hivyo tumekuwa kufunikwa integers.

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Nini hapo?

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>> Chars.

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Hivyo chars hutumiwa kwa vigezo
kwamba mapenzi kuhifadhi wahusika moja.

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Char ni mfupi kwa tabia.

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Na wakati mwingine unaweza kusikia
Watu kutamka hivyo kama gari.

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>> Hivyo wahusika daima kuchukua moja
Byte ya kumbukumbu, ambayo ni vipande tu 8.

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Hivyo hii ina maana kwamba wanaweza tu walionao
maadili katika aina mbalimbali ya hasi 2

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madarakani saba, au 128 hasi,
2 madarakani 7 bala 1, au 127.

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>> Shukrani kwa ASCII, ilikuwa
muda mrefu uliopita aliamua njia

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ramani wale idadi chanya kutoka
0-127 kwa wahusika mbalimbali

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kwamba yote yapo kwenye keyboard zetu.

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Hivyo kama tutaweza kuona baadaye katika
Bila shaka, na wewe utakuwa pengine

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kuja kukariri katika baadhi
uhakika, mji mkuu wa A, kwa example--

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mji mkuu tabia A--
ramani ya idadi 65.

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Na sababu ya kuwa ni
kwa sababu hiyo ni nini ni

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alipewa na kiwango cha ASCII.

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>> Lowercase A ni 97.

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Tabia 0 kwa wakati
kweli aina ya tabia, si

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anayewakilisha idadi sifuri, ni 48.

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Itabidi kujifunza wanandoa
ya hizi kama wewe kwenda.

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Na wewe utakuwa shaka kuja haja
nao kidogo baadaye katika CS50.

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>> Kuu ya pili data aina
ni yaliyo idadi uhakika.

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Hivyo yaliyo idadi hatua ni
Pia inajulikana kama idadi halisi.

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Wao ni kimsingi namba ambazo
kuwa alisema hatua ndani yao.

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Yaliyo maadili uhakika
kama integers ni pia

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zilizomo ndani ya 4 ka ya kumbukumbu.

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Sasa hakuna chati hapa.

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Hakuna mstari idadi, kwa sababu
kuelezea aina mbalimbali ya kuelea

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si hasa wazi au Intuitive.

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>> Inatosha kusema wewe
kuwa 32 bits kufanya kazi pamoja.

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Na kama una idadi
kama pi, ambayo ina

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integer sehemu 3, na yaliyo
hatua sehemu, au sehemu alisema 0.14159,

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na kadhalika, unahitaji kuwa
uwezo wa kuwakilisha zote wa hili

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integer sehemu na sehemu alisema.

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>> Basi je, unafikiri kwamba inaweza kumaanisha?

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Jambo moja ni kwamba kama alisema
sehemu anapata tena na tena,

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kama nina kubwa sana
sehemu integer, nipate si

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kuwa na uwezo wa kuwa kama sahihi
na sehemu alisema.

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Na kwamba ni kweli
kiwango cha juu ya kuelea.

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>> Ikifungwa na tatizo usahihi.

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Sisi tu bits 32 kwa
kazi na, ili tuweze tu

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kuwa hivyo sahihi na decimal yetu sehemu.

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Hatuwezi inge alisema
sehemu sahihi kwa tarakimu 100 au 200,

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kwa sababu sisi tu
32 bits kufanya kazi pamoja.

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Hivyo hiyo ni kiwango cha juu ya kuelea.

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>> Sasa kwa bahati nzuri kuna
aina nyingine inayoitwa data

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mara mbili, ambayo kwa kiasi fulani
inahusika na tatizo hili.

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Mara mbili, kama ikifungwa, pia kutumika kwa
kuhifadhi idadi halisi, au hatua yaliyo

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maadili.

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Tofauti ni kwamba
DOUBLES ni usahihi mara mbili.

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Wanaweza fit vipande 64 ya
data, au ka nane.

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Hiyo ina maana gani?

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Vizuri, ina maana tunaweza kuwa mengi zaidi
sahihi na decimal uhakika.

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Badala ya kuwa na pi hadi saba
maeneo labda, kwa kuelea,

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tunaweza labda wawe nao maeneo 30.

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Kama hiyo muhimu, unaweza kutaka
kutumia mara mbili badala ya kuelea.

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Kimsingi, kama wewe ni
kazi juu ya kitu chochote ambapo

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kuwa kweli kwa muda mrefu nafasi alisema
na mengi ya usahihi ni muhimu,

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pengine unataka
kutumia overfloat mbili.

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Sasa kwa zaidi ya kazi yako katika
CS50, kuelea lazima inatosha.

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Lakini tunajua kwamba mara mbili zipo kama
njia ya kiasi fulani kukabiliana na usahihi

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Tatizo kwa kutoa ziada 32
bits kufanya kazi na kwa namba yako.

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>> Sasa hii si aina data.

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Hii ni aina.

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Na ni kuitwa utupu.

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Na mimi nina kuzungumza kuhusu suala hilo
hapa kwa sababu tumekuwa pengine

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kuonekana ni mara chache tayari katika CS50.

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Na unaweza kuwa anashangaa
nini ni yote juu.

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>> Hivyo utupu ni aina.

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Ni gani zipo.

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Lakini siyo aina data.

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>> Hatuwezi kuunda kutofautiana wa aina
utupu na kuwapa thamani yake.

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Lakini kazi, kwa mfano,
unaweza kuwa na aina batili kurudi.

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Kimsingi, kama unaweza kuona kazi
ambayo ina aina batili kurudi,

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ina maana haina kurudi thamani.

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Je, unaweza kufikiria kawaida
kazi ambayo tumekuwa kutumika hadi sasa

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katika CS50 kwamba haina kurudi thamani?

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>> Printf ni moja.

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Printf haina kweli
kurudi kitu chochote na wewe.

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Prints kitu cha
screen, na ni kimsingi

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athari upande wa nini printf gani.

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Lakini haina kukupa thamani ya nyuma.

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Huwezi kukamata na kuhifadhi matokeo
hivyo katika baadhi ya kutofautiana kuitumia baadaye.

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Ni tu Prints kitu cha
screen na wewe ni kosa.

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>> Hivyo tunasema kwamba printf
ni batili kazi.

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Kuirudisha chochote.

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>> Mzunguko orodha ya
kazi inaweza pia kuwa batili.

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Na umefanya pia kuonekana kwamba
kidogo kabisa katika CS50 pia.

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Int kuu utupu.

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Je, hiyo kuwapigia kengele?

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Kimsingi nini maana ni kwamba
kuu haina kuchukua vigezo yoyote.

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Kuna hoja hakuna kwamba
kupata kupita katika kuu.

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Sasa baadaye tutaona kuwa kuna
njia ya kupita hoja ndani ya kuu,

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lakini hadi sasa nini tumekuwa
kuonekana ni int kuu utupu.

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Kuu tu haina kuchukua hoja yoyote.

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Na hivyo sisi bayana kwamba kwa kusema utupu.

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Sisi ni kuwa tu sana
wazi kuhusu ukweli

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kuwa haina kuchukua hoja yoyote.

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>> Hivyo kwa sasa, inatosha
kusema kwamba kimsingi ni batili

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lazima tu kutumika kama placeholder
kwa wewe kama kufikiri kuhusu kama si kitu.

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Siyo kweli kufanya kitu chochote.

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Hakuna kurudi thamani hapa.

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Hakuna vigezo hapa.

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Ni batili.

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Ni kidogo ngumu zaidi kuliko hiyo.

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Lakini hii lazima inatosha kwa
sehemu bora ya kozi.

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Na hopefully sasa una kidogo
kidogo zaidi ya dhana ya nini utupu ni.

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>> Basi hizo aina tano utasikia
kukutana kwamba ni kujengwa katika kwa C.

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Lakini katika CS50 sisi pia kuwa maktaba.

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CS50.h, ambayo unaweza ni pamoja na.

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Na ambayo itatoa
na aina mbili za ziada

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kwamba pengine utasikia kuwa na uwezo
kwa matumizi ya kazi yako,

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au tu kufanya kazi kwa ujumla programu.

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>> Ya kwanza ya haya ni bool.

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Hivyo data Boolean aina,
bool, ni kutumika kwa vigezo

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kwamba mapenzi kuhifadhi thamani Boolean.

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Kama wameweza milele kusikia
muda huu kabla, wewe

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wapate kujua ya kuwa Boolean
thamani ya uwezo wa pekee

195
00:08:31,960 --> 00:08:34,440
kuikopesha maadili mawili tofauti tofauti.

196
00:08:34,440 --> 00:08:35,872
Kweli na uongo.

197
00:08:35,872 --> 00:08:37,580
Sasa hii inaonekana pretty
msingi, sawa?

198
00:08:37,580 --> 00:08:40,496
Ni aina ya mshangao kwamba hii
haipo katika C kama ni kujengwa katika.

199
00:08:40,496 --> 00:08:42,640
Na katika lugha nyingi za kisasa,
bila shaka, Booleans

200
00:08:42,640 --> 00:08:45,390
ni kiwango cha aina data chaguo-msingi.

201
00:08:45,390 --> 00:08:47,192
Lakini katika C, wao ni kweli si.

202
00:08:47,192 --> 00:08:48,400
Lakini tumeunda ni kwa ajili yenu.

203
00:08:48,400 --> 00:08:51,910
Hivyo kama wewe milele haja ya kuunda
kutofautiana ambao ni aina bool,

204
00:08:51,910 --> 00:08:55,230
tu kuwa na uhakika wa CS50.h # ni pamoja na
mwanzoni mwa mpango wako,

205
00:08:55,230 --> 00:08:57,800
na wewe utakuwa na uwezo wa kujenga
vigezo vya aina bool.

206
00:08:57,800 --> 00:09:02,095
>> Kama kusahau # ni pamoja na CS50.h, na
kuanza kutumia Boolean-aina vigezo,

207
00:09:02,095 --> 00:09:04,970
unaweza kukutana baadhi ya matatizo
wakati wewe ni kuandaa programu yako.

208
00:09:04,970 --> 00:09:06,490
Hivyo tu kuwa juu ya Lookout kwa ajili hiyo.

209
00:09:06,490 --> 00:09:11,180
Na labda unaweza tu kurekebisha
matatizo na chupa ikiwa ni pamoja na CS50.h.

210
00:09:11,180 --> 00:09:14,590
>> Nyingine kubwa data aina kwamba sisi
kutoa kwa ajili yenu katika maktaba CS50

211
00:09:14,590 --> 00:09:15,670
ni kamba.

212
00:09:15,670 --> 00:09:17,130
Kwa hiyo kile ni kamba?

213
00:09:17,130 --> 00:09:18,520
Masharti ni kweli maneno tu.

214
00:09:18,520 --> 00:09:20,000
Wao ni makusanyo ya wahusika.

215
00:09:20,000 --> 00:09:20,640
Wao ni maneno.

216
00:09:20,640 --> 00:09:21,390
Wao ni hukumu.

217
00:09:21,390 --> 00:09:22,480
Wao ni aya.

218
00:09:22,480 --> 00:09:25,850
Inaweza kuwa vitabu nzima, hata.

219
00:09:25,850 --> 00:09:29,690
>> Mfupi sana kwa muda mrefu sana
mfululizo wa wahusika.

220
00:09:29,690 --> 00:09:34,310
Kama unahitaji kutumia masharti,
Kwa mfano, kuhifadhi neno,

221
00:09:34,310 --> 00:09:37,609
tu kuwa na uhakika wa ni pamoja na CS50.h
mwanzoni mwa mpango wako

222
00:09:37,609 --> 00:09:38,900
hivyo unaweza kutumia aina kamba.

223
00:09:38,900 --> 00:09:43,910
Na kisha unaweza kuunda vigezo
aina ambao ni data kamba.

224
00:09:43,910 --> 00:09:46,160
Sasa baadaye katika shaka,
tutaweza pia kuona kwamba hiyo ni

225
00:09:46,160 --> 00:09:47,752
si hadithi nzima, aidha.

226
00:09:47,752 --> 00:09:49,460
Tutaweza kukutana mambo
aitwaye miundo,

227
00:09:49,460 --> 00:09:54,249
ambayo itawawezesha kundi gani inaweza kuwa na
integer na kamba katika kitengo moja.

228
00:09:54,249 --> 00:09:56,290
Na tunaweza kutumia kwamba kwa
baadhi lengo, ambayo huenda

229
00:09:56,290 --> 00:09:57,750
kuja katika Handy baadaye katika shaka.

230
00:09:57,750 --> 00:09:59,500
>> Na tutaweza pia kujifunza
kuhusu aina inavyoelezwa,

231
00:09:59,500 --> 00:10:01,720
ambayo itawawezesha kujenga
data zako aina mwenyewe.

232
00:10:01,720 --> 00:10:03,060
Hatuna haja ya kuwa na wasiwasi
juu ya hilo kwa sasa.

233
00:10:03,060 --> 00:10:04,550
Lakini tu kujua kwamba hiyo ni
kitu juu ya upeo wa macho,

234
00:10:04,550 --> 00:10:07,633
kwamba kuna mengi zaidi ya yote hii
Aina ya neno kuliko mimi nawaambia tu

235
00:10:07,633 --> 00:10:08,133
sasa.

236
00:10:08,133 --> 00:10:10,591
Hivyo sasa kwamba tumejifunza
kidogo kuhusu data za msingi

237
00:10:10,591 --> 00:10:14,230
aina na aina CS50 data, hebu
majadiliano kuhusu jinsi ya kufanya kazi na vigezo

238
00:10:14,230 --> 00:10:18,530
na kujenga yao kwa kutumia hizi
aina ya data katika mipango yetu.

239
00:10:18,530 --> 00:10:22,670
Kama unataka kujenga kutofautiana,
wote unahitaji kufanya ni mambo mawili.

240
00:10:22,670 --> 00:10:24,147
>> Kwanza, unahitaji kuwapa aina.

241
00:10:24,147 --> 00:10:26,230
Jambo la pili unahitaji
kufanya ni kuwapa jina.

242
00:10:26,230 --> 00:10:28,740
Mara baada ya umefanya kosa hilo na kofi
semicolon mwishoni mwa mstari huo,

243
00:10:28,740 --> 00:10:29,830
umeunda kutofautiana.

244
00:10:29,830 --> 00:10:32,370
>> Hivyo hapa ni mifano miwili.

245
00:10:32,370 --> 00:10:35,744
Int idadi; barua char ;.

246
00:10:35,744 --> 00:10:36,660
Nimefanya nini hapa?

247
00:10:36,660 --> 00:10:38,110
Nimekuwa kuundwa vigezo mbili.

248
00:10:38,110 --> 00:10:40,190
>> Kwanza, kutofautiana ya
jina ni idadi.

249
00:10:40,190 --> 00:10:44,830
Na idadi ni uwezo wa kufanya integer
aina maadili, kwa sababu aina yake ni int.

250
00:10:44,830 --> 00:10:48,040
Barua ni mwingine kutofautiana
kwamba wanaweza kushikilia wahusika

251
00:10:48,040 --> 00:10:50,240
kwa sababu aina yake data ni char.

252
00:10:50,240 --> 00:10:51,772
>> Pretty moja kwa moja, sawa?

253
00:10:51,772 --> 00:10:53,480
Kama wewe mwenyewe kupata
katika hali ambapo

254
00:10:53,480 --> 00:10:56,250
unahitaji kujenga nyingi
vigezo vya aina moja,

255
00:10:56,250 --> 00:10:58,740
wewe tu haja ya kutaja
Aina ya jina moja.

256
00:10:58,740 --> 00:11:01,600
Kisha orodha tu vigezo kama wengi
ya aina hiyo kama unahitaji.

257
00:11:01,600 --> 00:11:04,230
>> Hivyo mimi naweza kwa mfano, hapa
katika mstari huu wa tatu wa kificho,

258
00:11:04,230 --> 00:11:07,420
kusema int urefu ;, mstari mpya.

259
00:11:07,420 --> 00:11:08,291
Int upana ;.

260
00:11:08,291 --> 00:11:09,290
Na kwamba ingekuwa kazi pia.

261
00:11:09,290 --> 00:11:12,039
Ningependa bado kupata vigezo mbili inaitwa
urefu na upana, ambayo kila mmoja

262
00:11:12,039 --> 00:11:12,730
ni integer.

263
00:11:12,730 --> 00:11:16,970
Lakini mimi nina kuruhusiwa, mambo ya C syntax,
kuimarisha ndani line moja.

264
00:11:16,970 --> 00:11:20,230
Int urefu, upana; Ni kitu kimoja.

265
00:11:20,230 --> 00:11:23,900
Nimekuwa kuundwa vigezo mbili, moja inaitwa
urefu mtu mmoja aitwaye upana, wote wawili ambao

266
00:11:23,900 --> 00:11:26,730
wana uwezo wa kufanya
integer aina maadili.

267
00:11:26,730 --> 00:11:30,920
>> Vile vile hapa, siwezi kujenga tatu
yaliyo maadili uhakika kwa mara moja.

268
00:11:30,920 --> 00:11:33,350
Siwezi labda kuunda kutofautiana
aitwaye mraba mzizi wa 2--

269
00:11:33,350 --> 00:11:35,766
ambayo pengine hatimaye
kushikilia point-- yaliyo

270
00:11:35,766 --> 00:11:39,222
kuwa uwakilishi wa mraba
mzizi wa 2-- mraba mizizi ya 3, na pi.

271
00:11:39,222 --> 00:11:41,180
Mimi wangefanya hii
juu ya mistari tatu tofauti.

272
00:11:41,180 --> 00:11:47,690
Kuelea, mraba mzizi 2; Kuelea mraba mizizi
3; kuelea pi; na kwamba ingekuwa kazi pia.

273
00:11:47,690 --> 00:11:50,590
>> Lakini tena, naweza tu kuimarisha
huu katika line moja ya kanuni.

274
00:11:50,590 --> 00:11:54,050
Hufanya mambo kidogo
mfupi, si kama clunky.

275
00:11:54,050 --> 00:11:57,259
>> Sasa kwa ujumla, ni kubuni nzuri ya tu
kutangaza kutofautiana wakati unahitaji kuwa.

276
00:11:57,259 --> 00:11:59,050
Na tutaweza kuongea kidogo
kidogo zaidi kuhusu kwamba

277
00:11:59,050 --> 00:12:00,945
baadaye katika shaka
wakati sisi kujadili upeo.

278
00:12:00,945 --> 00:12:03,320
Hivyo si lazima haja ya
kujenga wote wa vigezo yako

279
00:12:03,320 --> 00:12:05,990
mwanzoni mwa mpango, ambayo
baadhi ya watu wanaweza kuwa amefanya siku za nyuma,

280
00:12:05,990 --> 00:12:08,700
au kwa hakika kawaida sana
coding mazoezi miaka mingi iliyopita

281
00:12:08,700 --> 00:12:11,700
wakati wa kufanya kazi na C. Wewe nguvu tu
unataka kujenga kutofautiana haki wakati

282
00:12:11,700 --> 00:12:13,140
unahitaji yake.

283
00:12:13,140 --> 00:12:13,640
Sawa.

284
00:12:13,640 --> 00:12:15,150
Hivyo tumeunda vigezo.

285
00:12:15,150 --> 00:12:16,790
Je, sisi matumizi yao?

286
00:12:16,790 --> 00:12:18,650
Baada ya sisi kutangaza
kutofautiana, hatuna haja

287
00:12:18,650 --> 00:12:21,237
kutaja aina data
ya kwamba kutofautiana tena.

288
00:12:21,237 --> 00:12:24,070
Kwa kweli, kama wewe kufanya hivyo, waweza
kuishia na baadhi ya matokeo weird

289
00:12:24,070 --> 00:12:25,490
kwamba tutaweza aina ya Gloss juu kwa sasa.

290
00:12:25,490 --> 00:12:27,365
Lakini inatosha kusema,
mambo weird ni kwenda

291
00:12:27,365 --> 00:12:30,740
kuanza kinachotokea kama wewe inadvertently
tena kutangaza vigezo kwa jina moja

292
00:12:30,740 --> 00:12:32,210
tena na tena.

293
00:12:32,210 --> 00:12:33,882
>> Hivyo hapa nina mistari minne ya kanuni.

294
00:12:33,882 --> 00:12:36,090
Na mimi kuwa wanandoa wa
maoni huko kuonyesha tu

295
00:12:36,090 --> 00:12:37,840
nini kinatokea kwenye
kila mstari tu kusaidia

296
00:12:37,840 --> 00:12:40,520
kupata uliojengwa katika nini kinaendelea.

297
00:12:40,520 --> 00:12:41,520
Hivyo int idadi ;.

298
00:12:41,520 --> 00:12:42,520
Ninyi kuona kwamba hapo awali.

299
00:12:42,520 --> 00:12:44,000
Hiyo ni tamko kutofautiana.

300
00:12:44,000 --> 00:12:46,670
>> Nimekuwa sasa umba kutofautiana
kuitwa idadi hiyo

301
00:12:46,670 --> 00:12:48,970
uwezo wa kufanya maadili integer-aina.

302
00:12:48,970 --> 00:12:50,210
Nimekuwa amekiri kuwa ni.

303
00:12:50,210 --> 00:12:53,770
>> Mstari unaofuata mimi nina kumshirikisha
thamani ya idadi.

304
00:12:53,770 --> 00:12:54,992
Idadi sawa na 17.

305
00:12:54,992 --> 00:12:55,950
Nini kinatokea huko?

306
00:12:55,950 --> 00:12:58,880
Mimi nina kuweka namba 17
ndani ya kwamba kutofautiana.

307
00:12:58,880 --> 00:13:02,760
>> Hivyo kama mimi milele kisha magazeti nje nini
yaliyomo ya idadi ni baadaye,

308
00:13:02,760 --> 00:13:04,030
wao itabidi kuniambia ni 17.

309
00:13:04,030 --> 00:13:07,030
Hivyo nimekuwa alitangaza kutofautiana,
na kisha nimekuwa kupewa yake.

310
00:13:07,030 --> 00:13:10,570
>> Tunaweza kurudia utaratibu
tena kwa char barua ;.

311
00:13:10,570 --> 00:13:11,640
Hiyo ni tamko.

312
00:13:11,640 --> 00:13:14,010
Barua ni sawa na mji mkuu
H. Hiyo ni kazi.

313
00:13:14,010 --> 00:13:16,030
Pretty moja kwa moja, pia.

314
00:13:16,030 --> 00:13:18,319
>> Sasa mchakato huu nguvu
wanaonekana aina ya silly.

315
00:13:18,319 --> 00:13:20,110
Kwa nini tunafanya hivi
katika mistari miwili ya kificho?

316
00:13:20,110 --> 00:13:21,401
Je, kuna njia bora ya kufanya hivyo?

317
00:13:21,401 --> 00:13:22,250
Kwa kweli, kuna.

318
00:13:22,250 --> 00:13:24,375
Wakati mwingine unaweza kuona
hii inaitwa initialization.

319
00:13:24,375 --> 00:13:28,446
Ni wakati kutangaza kutofautiana
na kuwapa thamani kwa wakati mmoja.

320
00:13:28,446 --> 00:13:30,320
Hii ni kweli pretty
jambo la kawaida kufanya.

321
00:13:30,320 --> 00:13:32,870
Wakati kujenga kutofautiana, kwa kawaida
nataka kuwa na baadhi ya thamani ya msingi.

322
00:13:32,870 --> 00:13:34,330
Hata kama ni 0 au kitu.

323
00:13:34,330 --> 00:13:36,180
Wewe tu wewe kuwapa thamani.

324
00:13:36,180 --> 00:13:38,360
>> Unaweza initialize kutofautiana.

325
00:13:38,360 --> 00:13:42,320
Int idadi sawa na 17 ni sawa na
kwanza mistari miwili ya kificho up hapo juu.

326
00:13:42,320 --> 00:13:46,829
Char barua sawa na h ni sawa na
tatu na cha nne mstari wa kanuni juu.

327
00:13:46,829 --> 00:13:49,620
Takeaway muhimu zaidi hapa
wakati sisi ni kutangaza na kumshirikisha

328
00:13:49,620 --> 00:13:51,740
vigezo ni baada tumekuwa
amekiri kuwa ni, ilani

329
00:13:51,740 --> 00:13:53,700
Mimi si kutumia aina data tena.

330
00:13:53,700 --> 00:13:57,916
Sisemi int idadi sawa na 17 juu ya
mstari wa pili wa kanuni, kwa mfano.

331
00:13:57,916 --> 00:13:59,290
Mimi tu kusema idadi ni sawa na 17.

332
00:13:59,290 --> 00:14:02,537
>> Tena, re-kutangaza variable baada ya
umefanya tayari alitangaza inaweza kusababisha

333
00:14:02,537 --> 00:14:03,620
kwa baadhi matokeo weird.

334
00:14:03,620 --> 00:14:05,950
Hivyo tu kuwa makini ya kwamba.

335
00:14:05,950 --> 00:14:06,660
>> Mimi nina Doug Lloyd.

336
00:14:06,660 --> 00:14:08,870
Na hii ni CS50.

337
00:14:08,870 --> 00:14:10,499