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[Powered by Google Translate] SPIKA 1: Hii ni CS50.

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Basi nikawa ambapo wewe ni sasa baadhi ya miaka iliyopita, na wakati mimi nilikuwa katika Freshman

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muda, mimi si kweli juu ya njia hii ya kufanya kompyuta sayansi, ya kufanya

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uhandisi.

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Hakika, nilikwenda katika eneo hili kama concentrator serikali.

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Ningependa kuwa katika shule ya sekondari kid ambao walipenda mambo kama historia.

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Mimi walipenda sheria ya katiba, aina ya Kiingereza na Hisabati, hivyo aina ya

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vizuri mviringo, lakini haikuwa lazima kujua mambo ambayo sikuwa wamefundishwa

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katika shule ya sekondari.

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Na hivyo mwaka Freshman, nilikuwa hii trepidation, ambapo hata mimi

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walipenda kompyuta, kucheza michezo ya kompyuta na kama, mimi bila ya shaka kamwe

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mawazo ya mtu mwenyewe kama kompyuta, mwanasayansi wa kompyuta, na

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kusema ukweli, nilifikiri rafiki yangu katika shule ya sekondari ambao walikuwa kuchukua kompyuta

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sayansi walikuwa kidogo ya - geeks.

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>> Na bado, nilipofika hapa juu ya chuo, kulikuwa na kozi hii, CS50, na katika

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wakati, alikuwa na sifa hii ya kweli kuwa kitu kwa tahadhari.

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Ilikuwa mwelekeo mzuri.

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Ilikuwa shaka ya fun.

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Lakini alikuwa na kwamba kweli kupata mguu katika mlango.

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Na hata sikuweza kuvuka kizingiti kwamba Freshman mwaka.

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Na mimi akaenda wangu kuwa concentrator serikali, kwenda kupitia

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kama wengi wa prerequisites kama niwezavyo, kuvuka kuhesabu mambo kwa gen

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ed au msingi na mwaka kama, na kisha sophomore, kwa sababu fulani, I got

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up ujasiri hatua ya mguu katika Sayansi Center B, ambapo CS50.

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maarufu sana kompyuta mwanasayansi kwa jina la Brian Kernighan ilikuwa

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kufundisha hapa kwamba mwaka, na hata basi, nilikuwa tayari tu kwa kweli

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kujaza utafiti kadi yangu kwa kuchukua darasa hili kupita / kushindwa.

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Nikaona kuzunguka yangu, na mimi figured kila mtu katika chumba hiki got kujua

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njia zaidi kuhusu sayansi ya kompyuta, kuhusu programu, kuhusu kompyuta.

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Kila mmoja lazima programu katika chumba hiki tangu walipokuwa 12, lakini kwa kweli,

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kwamba haikuwa hivyo.

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Na hivyo siku ya mwisho kabisa, Jumatatu ya tano ya muhula kwamba mimi kuchukua

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hii ataruka na mabadiliko kutoka kupita / kushindwa daraja barua, na kuishia kubadilisha yangu

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ukolezi siku hiyo kwa sayansi ya kompyuta.

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>> Sasa kwamba si lengo letu katika darasa hili, kugeuka wewe wote ndani ya kompyuta

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sayansi concentrators, lakini kwa kweli, kupendekeza kwamba kuna nafasi hii

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katika uwanja huu na katika maeneo mengine ambayo unaweza kuwa na kabisa unfamiliar,

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kutokana na kwamba shule za sekondari kawaida kufuata mtaala uungwana kiwango

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njia, lakini hawajitokezi katika, katika CS50, ndani ya maji mpya.

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Na kama wewe ni kukaa hapa leo kufikiri wewe si kweli ni mali, hivyo

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kufanya zaidi ya watu kwa haki yako na kwa upande wako wa kushoto.

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Hakika, mwaka jana, 76% ya wanafunzi katika darasa hili hawakuwa na uzoefu kabla.

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Hivyo kinyume na kile wewe kufikiri, zaidi ya watu wamekaa kuzunguka wewe

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leo hawana, kwa kweli, kuwa na uzoefu wowote kabla.

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18% wamechukua moja CS darasa, na 6% wamechukua mbili au zaidi.

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Wakati huo huo, tunaomba wanafunzi wetu kila mwaka kuelezea wenyewe katika suala

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wa ngazi ya faraja, na hii ni -

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hakuna ufafanuzi mmoja wa hii.

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Wewe tu aina ya kujua hayo, kama wewe si vizuri sana katika CS50.

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Na mwaka jana, tulikuwa na 55% katika kipande hii ya kijani pie hapa, binafsi kuelezea

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kama wanafunzi chini starehe ambao kusema ukweli sisi hakuwa na wazo why'd wao

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duka bila shaka siku hiyo ya kwanza, lakini sawa 55% walibaki pamoja nasi mpaka

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mwisho mrefu, kama alivyofanya 35%, ambao walikuwa mahali fulani katika kati ya wale zaidi

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starehe na walio chini starehe.

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>> Hivyo kile ni sayansi ya kompyuta?

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Naam, katika shule ya sekondari, na kwa kweli, kwa ujumla zaidi huko nje siku hizi,

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kuna hii mtazamo au hii mbaya kwamba sayansi ya kompyuta ni

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programu.

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Na kwamba kabisa hali moja ya sayansi ya kompyuta, lakini programu,

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lugha yoyote ni, ni kweli tu kwamba chombo kompyuta wanasayansi

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kuzitumia kutatua matatizo, aidha katika uwanja wa sayansi ya kompyuta au,

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inazidi siku hizi, katika sayansi ya michezo, asili

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sayansi, katika dawa, katika masomo ya sanaa, kuchambua

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kubwa seti ya data.

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Popote sasa kuna kompyuta na data, kuna nafasi ya kuomba

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mambo ya kujifunza katika darasa kama CS50.

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>> Basi hebu kutatua tatizo kwamba mwanasayansi kompyuta mnavyoweza

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kutatua na kujaribu kuweka baadhi jargon, kuweka baadhi ya mfumo wa dhana, karibu

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nini ili vinginevyo kuwa baadhi ya mawazo haki ya kufikirika.

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Hivyo hii ni simu.

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Huwezi kuona mambo hayo mara nyingi mno.

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chuo bado inaonekana kuwa haya katika nyumba na mabweni, lakini

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nyuma katika siku, wakati wewe alitaka kutumia simu kama hii, kulikuwa hakuna

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elektroniki anuani kitabu katika simu yako ya mkononi.

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Badala yake, wewe vunjwa up kitu inayojulikana kama kitabu ya simu, na vitabu hivi simu

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alikuwa kuhusu 1,000 kurasa kawaida.

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Walikuwa sorted kutoka A to Z, na wewe tu alikuwa na kupata haki ya ukurasa

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kupata mtu wewe ni kuangalia kwa ili kupata jina yao na wao

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namba ya simu.

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Sasa ni jinsi gani unaweza kwenda juu ya kuangalia up mtu katika kitabu hiki?

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>> Tuseme lengo langu ni kuwapa rafiki yangu Mike Smith wito.

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Naam, jinsi gani mimi kwenda juu ya kutafuta Mike Smith?

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Naam, mbinu nzuri sana, kama naive na ufanisi, itakuwa kuanza

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hapa, na kuanza flipping kwa ukurasa wa nne, ukurasa wa tano, ukurasa wa sita, na kutatua

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ya linearly, pamoja mstari sawa, kupitia kitabu hiki simu, na hata

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ingawa ni ya kwenda kuwa incredibly tedious, kama Mike Smith ni katika hii

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kitabu, mimi nina hatimaye kwenda kufikia naye wakati mimi hatimaye flip kwa S

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sehemu ya kitabu hiki.

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Sasa, bila shaka, huna haja ya kuwa na mwanasayansi wa kompyuta kwa kujua kwamba hii

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ni njia ya kijinga ya kutatua tatizo hili.

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Gani binadamu wa kawaida kuwa kufanya?

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Vema.

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Hivyo ungependa flip katikati, haki?

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Hivyo wewe d flip takribani katikati, angalia hapa, na mimi wanaonekana kupata mwenyewe

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katika sehemu M.

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Sawa, hivyo M ni wazi siyo kile mimi nina kuangalia kwa.

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Mike ni kwa haki, ili kuzungumza, wa sehemu hii, na kama baadhi yenu

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kuona mbele, tunaweza sasa kuendelea na literally chozi hii

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tatizo katika nusu.

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>> Wewe kweli haipaswi kuwa hisia.

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Tearing ni chini mshono ni kweli si vigumu.

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watu halisi kufanya hivyo kwa njia hii, lakini chini mshono, sisi

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sasa una matatizo mawili.

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Kila moja ya ambayo ni nusu kama kubwa, na tunaweza literally kutupa kwamba nusu ya

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tatizo mbali.

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Sasa tuko kushoto si kwa kurasa 1,000, lakini kusema, 500.

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Hivyo sasa nini mimi?

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Naam, binadamu wa kawaida kwenda takribani katikati tena, na mimi kupata mwenyewe katika

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Sehemu R, hivyo si kabisa huko.

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Hivyo tena, siwezi machozi tatizo hili katika nusu.

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Asante.

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Hivyo sasa mimi tu baadhi ya kurasa 250, na mimi siwezi kufanya hivyo tena, na tena, na

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tena, na kwenda kutoka 125 hadi takribani 60, hadi 30, hadi 15, na kadhalika.

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Na hatimaye, mimi itabidi kupata yameshuka kwa moja ya kurasa S, ambayo, kama yeye ni

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katika kitabu cha simu, Mike Smith lazima.

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>> Sasa hiyo ni algorithm wazi haki ya kuridhisha, na ni

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moja wakati matumizi algorithm katika kesi hii, lakini nini tunaweza aina ya

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kuchukua mbali na kwamba?

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Naam, mbinu ya kwanza, sahihi, kama wasiojua, ingawa, ilikuwa, unaweza kuwa

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ilivyoelezwa na mstari huu moja kwa moja.

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Hivyo kama juu ya x-mhimili, sisi hapa kusema, hii ni kawaida ya tatizo.

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Hivyo kama x-mhimili inakwenda haki, tatizo anapata kubwa.

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Ina maana gani kuwa kubwa?

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Katika muktadha wa tatizo hili, zaidi ya kurasa katika kitabu cha simu.

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Kuna zaidi kitu tunaweza kupima.

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On y-mhimili, wakati wa kutatua.

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Hivyo kama mhimili huenda juu, sisi ni presume ikatengeneza inachukua muda zaidi.

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Hivyo kwamba njia ya kwanza ya linearly kutafuta kutoka ukurasa mmoja kwa ukurasa 1000

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ni utaratibu linear, algorithm linear au mchakato, na tunaweza

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kueleza ni kwa mstari huu moja kwa moja.

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Kama mimi kuongeza moja zaidi ukurasa wa kitabu cha simu, ni kwenda, katika mbaya

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kesi, kuchukua mimi moja zaidi ukurasa flip kupata Mike Smith.

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Kama mimi kuongeza kurasa 100, 100 zaidi flips, au vitengo ya muda.

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>> Sasa naweza kuwa wajanja kidogo na hili.

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Sihitaji kwa kweli kugeuka ukurasa mmoja kwa wakati.

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Naweza kufanya mambo kama wawili kwa wakati au nne kwa wakati, lakini hata hilo si

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wote kwamba kimsingi bora.

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Hata kama ni wawili kwa wakati, yeah, kwamba aina ya hatua hii mstari chini kidogo,

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na maana yake ni kwamba inachukua muda kidogo, kutokana na idadi sawa ya kurasa, lakini

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si kimsingi bora.

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Lakini je, sisi tu kufanya, na ni nini yote ya wewe kufanya instinctively?

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Wewe kweli mafanikio kitu kidogo kama hii, logarithmic muda,

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ambapo tatizo inaweza kukua na kukua na kukua, lakini gharama ya kutatua kwamba

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tatizo, wakati required kutatua tatizo, haina

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kukua karibu kama kufunga.

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Hii itakuwa Curve logarithmic, logi ya n, ambapo n ni tu katika ukubwa wa

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tatizo, idadi ya kurasa katika kitabu hiki simu.

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Na nini maana ya hii katika hali halisi?

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Naam, kama sisi, kama, watu 500 katika chumba hiki hivi sasa -

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au tuseme, kama tuna -

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kuchanganya Fumbo -

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hakufanya hivyo mfano bado mwaka huu - hivyo kama tuna 500 kurasa katika simu

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kitabu, na sisi mara mbili kwa 1000, katika mfano huu akili zaidi ya

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flipping kwa katikati, jinsi wengi zaidi ukurasa-tearers gani kuchukua kwenda kutoka

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500 kurasa 1000?

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Naam, moja tu ya ziada ukurasa machozi.

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Kama wewe mitupu yangu 2000 ukurasa simu kitabu, hakuna mpango mkubwa.

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Ningependa tu machozi moja ya ziada wakati.

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>> Hivyo katika muda mfupi, na ukubwa wa tatizo unaweza kukua kwa kasi zaidi kuliko gharama ya

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kweli kulitatua.

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Sasa hii ni moja tu vile algorithm.

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Kuna wengine tunaweza kutatua kwa njia hii hii.

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Na hivyo kwa nini sio sisi kufanya hili - kama ungependa ucheshi yangu, angalau awkwardly hapa

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katika Sanders, kwenda mbele, kila mtu, kama unaweza, na kusimama katika mahali.

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Kama unaweza kuona kwenye screen hapa, hii ni algorithm, mchakato, kompyuta

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mpango, kama wewe, wauawe na binadamu, ambayo ina tu hatua tatu.

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Sisi ni tayari juu ya hatua moja, ve alisimama.

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Na sasa kufikiria mwenyewe namba moja.

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Hiyo ni idadi yako ya sasa.

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Kila mtu hapa ni namba moja.

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Hatua mbili, jozi up na mtu amesimama na namba yako pamoja,

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na kisha kupitisha hii Jumla kama namba yako mpya.

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Moja ya unapaswa kukaa chini, kisha kurudia.

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>> Katika hatua hii, wachache zaidi watu lazima amesimama.

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Hii ni ambapo anapata zaidi Awkward.

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Mtu hapa, hapa.

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sehemu mbaya zaidi ni, wewe pia sana maneno kufanya hesabu mbele

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ya mamia ya Harvard undergrads.

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Okay, kidogo ya mdudu hapa.

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Sawa, nini namba yako?

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Tisa.

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Sawa.

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Nini namba yako?

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179.

185
00:10:57,710 --> 00:10:58,470
Okay, nzuri.

186
00:10:58,470 --> 00:10:59,420
Hivyo 188.

187
00:10:59,420 --> 00:11:00,570
Hivyo wewe guys wanaweza kukaa chini.

188
00:11:00,570 --> 00:11:02,320
Nini namba yako?

189
00:11:02,320 --> 00:11:04,420
118.

190
00:11:04,420 --> 00:11:07,440
Baadhi ya undergrad smart kuanza kufanya math.

191
00:11:07,440 --> 00:11:09,180
Okay, 118, 188.

192
00:11:09,180 --> 00:11:10,430
Nini kingine tulipata?

193
00:11:13,120 --> 00:11:16,450
71.

194
00:11:16,450 --> 00:11:17,650
79.

195
00:11:17,650 --> 00:11:18,260
Sawa.

196
00:11:18,260 --> 00:11:20,220
Na?

197
00:11:20,220 --> 00:11:23,240
47, ambayo, walimu, kwamba inatupa ngapi?

198
00:11:26,250 --> 00:11:29,830
705 ni jibu.

199
00:11:29,830 --> 00:11:32,045
Na kwamba, kwa kweli, hasa sahihi.

200
00:11:37,250 --> 00:11:40,080
>> Hapana, sisi walikuwa kweli kidogo mbali huko, lakini jinsi

201
00:11:40,080 --> 00:11:41,220
wanapaswa kuwa na kazi hii?

202
00:11:41,220 --> 00:11:44,080
Nini tu kilichotokea?

203
00:11:44,080 --> 00:11:48,270
Kadhalika kila iteration ya algorithm hii, sisi ilianza na idadi baadhi

204
00:11:48,270 --> 00:11:51,480
ya watu wakiwa wamesimama, na kwamba alikuwa jumla ya idadi, n, mara ya kwanza.

205
00:11:51,480 --> 00:11:53,880
Kisha nusu ya wewe wakaketi, na sisi akaenda n juu ya mbili.

206
00:11:53,880 --> 00:11:57,570
Kisha nusu ya wewe wakaketi, sisi akaenda n zaidi ya nne, n juu ya nane, zaidi ya 16,

207
00:11:57,570 --> 00:12:01,220
na kadhalika, mpaka, hata kama ni aina ya disintegrated huko

208
00:12:01,220 --> 00:12:04,760
mwisho, katika nadharia, kila mtu alikuwa paired mbali katika balcony, na mezzanine, na

209
00:12:04,760 --> 00:12:10,180
orchestra hapa, tungekuwa na moja tu lone mtu amesimama, na jumla ya

210
00:12:10,180 --> 00:12:13,930
thamani, katika kesi hii, ya 705.

211
00:12:13,930 --> 00:12:16,600
Sasa nini maana ya kuwa, ingawa, kwa mara ya mbio?

212
00:12:16,600 --> 00:12:18,960
Naam, fikiria kama mimi, kama binadamu, alikuwa amefanya manually.

213
00:12:18,960 --> 00:12:22,602
Ningependa kuanza uungwana naively lakini kwa usahihi kwa moja, mbili, tatu,

214
00:12:22,602 --> 00:12:27,060
nne, tano, sita, saba, nane, na kadhalika; inachukua kabisa baadhi ya wakati.

215
00:12:27,060 --> 00:12:28,120
Hivyo siwezi kufanya vizuri, haki?

216
00:12:28,120 --> 00:12:29,830
Katika shule ya daraja, si tu katika kuhesabu ndio.

217
00:12:29,830 --> 00:12:30,580
Kuhesabu wawiliwawili.

218
00:12:30,580 --> 00:12:32,190
Hivyo mbili, nne, sita, nane, kumi, kumi na mbili.

219
00:12:32,190 --> 00:12:36,210
Na kwamba anapata kasi zaidi, lakini sasa kimsingi, kwa leveraging

220
00:12:36,210 --> 00:12:39,710
pamoja akili ya kila mmoja katika nafasi hii, tunaweza kufikia Curve sana

221
00:12:39,710 --> 00:12:43,750
zaidi kama hii, ambapo sasa, idadi ya watu katika chumba hiki

222
00:12:43,750 --> 00:12:48,570
inaweza mara mbili, mwingine watu 700 kutembea ndani ya chumba hiki kwa watu 1,400, lakini

223
00:12:48,570 --> 00:12:53,010
ingekuwa tu kuchukua yetu moja zaidi iteration ya hii algorithm kutatua.

224
00:12:53,010 --> 00:12:55,970
>> Na hivyo kuongezeka, siku hizi, wakati sisi tuna data hizi kubwa anaweka katika

225
00:12:55,970 --> 00:12:59,690
Facebook, na Google, na kama, ni kutatua matatizo na hii kidogo ya

226
00:12:59,690 --> 00:13:04,060
ufahamu, hii kidogo ya ujanja, kwamba ni kuruhusu sisi inazidi kufanya mengi,

227
00:13:04,060 --> 00:13:07,290
sana na nguvu zaidi mambo na kompyuta ya leo.

228
00:13:07,290 --> 00:13:10,440
Kama wewe kama hizi aina ya mambo, wewe aliyoiona kwenye Facebook CS50 ya

229
00:13:10,440 --> 00:13:12,990
mwenyewe Puzzle Day, kuja Jumamosi hii.

230
00:13:12,990 --> 00:13:15,860
Kama ungependa kushiriki katika kitu kama hii, ambapo wewe na

231
00:13:15,860 --> 00:13:20,470
mbili, au tatu, au timu nne ya nne ungependa kutatua puzzles baadhi ya vile

232
00:13:20,470 --> 00:13:25,030
kama hii moja, unaweza kusimama nafasi ya kushinda zawadi ya baadhi fabulous, kati ya ambayo ni

233
00:13:25,030 --> 00:13:29,130
Wii, na kadi baadhi ya zawadi, na baadhi nyingine Facebook swag Jumamosi hii,

234
00:13:29,130 --> 00:13:30,770
mchana kwa PM 03:00.

235
00:13:30,770 --> 00:13:35,590
Nenda cs50.net/rsvp kwa vile.

236
00:13:35,590 --> 00:13:38,070
Na hii ni slide online kama Ningependa kucheza karibu.

237
00:13:38,070 --> 00:13:40,170
puzzles mwaka huu utakuwa mpya.

238
00:13:40,170 --> 00:13:43,350
>> Unaweza taarifa ya darasani, pia, kamera zote zaidi mwaka huu.

239
00:13:43,350 --> 00:13:47,950
Hivyo si tu bila shaka zingine katika njia ya kawaida, CS50 inaweza pia kuwa

240
00:13:47,950 --> 00:13:51,230
kuchukua sehemu katika documentary katika elimu ya juu ambacho kuangalia

241
00:13:51,230 --> 00:13:54,460
transformative uzoefu kwamba mwanafunzi anaweza kuwa na siku hizi katika

242
00:13:54,460 --> 00:13:56,010
shahada ya kwanza ya mwendo wa utafiti.

243
00:13:56,010 --> 00:14:00,340
Hivyo mwishoni hizi, sio tu tutakuwa filming kwa kuwa, tutaweza kuwa na sinema

244
00:14:00,340 --> 00:14:04,700
kama vile kwa, inazidi, watazamaji wetu online, kama vile, juu ya tukio,

245
00:14:04,700 --> 00:14:05,810
hii watazamaji hapa.

246
00:14:05,810 --> 00:14:09,120
Hivyo sisi kuwakaribisha kwa darasa mwaka huu wetu Harvard wanafunzi wa shule za ugani,

247
00:14:09,120 --> 00:14:12,060
kuhitimu shule ya kubuni, elimu, shule ya biashara, Kennedy

248
00:14:12,060 --> 00:14:15,600
Shule, shule ya sheria, kama vile idadi ya wanafunzi kutoka Belmont,

249
00:14:15,600 --> 00:14:18,280
Lexington, Newton, na Watertown Shule Kuu.

250
00:14:18,280 --> 00:14:19,250
Karibu yote.

251
00:14:19,250 --> 00:14:22,330
Aidha, mwaka huu, kama wewe kuwa na habari, Harvard, na MIT, na

252
00:14:22,330 --> 00:14:25,740
Berkeley sasa wameingia katika ushirikiano wa pamoja juu ya

253
00:14:25,740 --> 00:14:30,490
Mpango huo wa EdX, ambayo ni mpango wa kufungua elimu kwa wote

254
00:14:30,490 --> 00:14:34,010
watu zaidi online na, kimsingi, kuanza kufanya utafiti juu ya

255
00:14:34,010 --> 00:14:36,530
wadogo pana sana kama jinsi watu kujifunza.

256
00:14:36,530 --> 00:14:39,960
Na hivyo CS50 itakuwa chuo cha kwanza bila shaka kushiriki katika kwamba

257
00:14:39,960 --> 00:14:42,960
mpango huo, kama vile, ambayo ina maana utakuwa na upatikanaji kwa wote zaidi

258
00:14:42,960 --> 00:14:46,890
zana, maudhui yote zaidi mtaala, zaidi ya yote maudhui ya video kama

259
00:14:46,890 --> 00:14:52,410
Matokeo yake, kama vile ya jana asubuhi, watu 53,019 ambao wana

260
00:14:52,410 --> 00:14:56,825
kusajiliwa na kuchukua CS50 pamoja na wewe mwaka huu kwenye mtandao.

261
00:15:05,940 --> 00:15:08,830
Hivyo hii ina maana gani, hasa, ni kwamba wafanyakazi wa kufundisha na nina

262
00:15:08,830 --> 00:15:12,080
alitumia kidogo kabisa ya wakati huu wa majira ya maandalizi kwa ajili ya kuanguka, wote juu ya kampasi

263
00:15:12,080 --> 00:15:15,720
na mbali, ili tuweze kuanza kujenga Corpus ya kuvutia, ya

264
00:15:15,720 --> 00:15:20,760
kulazimisha, ya kujishughulisha maudhui ya elimu, ambayo inalenga hasa kwenye

265
00:15:20,760 --> 00:15:26,090
ionekane zaidi conveyances ya nyenzo uungwana tata.

266
00:15:26,090 --> 00:15:28,540
>> Hivyo kwa kuongeza mihadhara shaka, na sehemu, na mambo

267
00:15:28,540 --> 00:15:31,810
inayoitwa walkthroughs, ambayo tutaweza kupitia upya katika kidogo tu, tutaweza pia kuwa

268
00:15:31,810 --> 00:15:35,090
haya kaptula mwaka huu kwamba kuruhusu kujihusisha na shaka kutoka

269
00:15:35,090 --> 00:15:36,660
tofauti angle wote pamoja.

270
00:15:36,660 --> 00:15:39,610
Basi hebu kutumia hii kama fursa ya kuchukua Peek haraka katika moja kwamba

271
00:15:39,610 --> 00:15:41,460
kujadili wazo hili la binary.

272
00:15:41,460 --> 00:15:44,890
>> Hivyo katika sayansi ya kompyuta kuna mambo kuitwa algorithms, wawili ambao

273
00:15:44,890 --> 00:15:47,870
sisi tu alichukua kuangalia - taratibu hizi kwa ajili ya kutatua matatizo.

274
00:15:47,870 --> 00:15:51,060
Lakini mwisho wa siku, unahitaji kuwakilisha taarifa kwa namna fulani, na wewe

275
00:15:51,060 --> 00:15:54,540
haja ya kuwakilisha hivyo kwa njia ambayo kompyuta anaweza kuelewa.

276
00:15:54,540 --> 00:15:57,330
Na hata kama wewe si kweli kuelewa kompyuta, na uko katika

277
00:15:57,330 --> 00:16:01,470
kwamba 76% hivi sasa, pengine baadhi ya hisia hazieleweki kwamba kompyuta

278
00:16:01,470 --> 00:16:05,300
namna fulani katika mpango zeros na ndio, mfumo binary, hivyo kusema.

279
00:16:05,300 --> 00:16:06,630
Sasa kwa nini ni kwamba kesi?

280
00:16:06,630 --> 00:16:10,120
Naam, zinageuka wakati kompyuta ya kwanza alikuja juu, ikiwa inahitajika kuwakilisha

281
00:16:10,120 --> 00:16:13,810
habari, unaweza kufanya hivyo pamoja na umeme, na ingawa hii ni kidogo

282
00:16:13,810 --> 00:16:18,140
ya kurahisisha, njia rahisi sana ya habari kurekodi ni aidha

283
00:16:18,140 --> 00:16:22,600
na kugeuka ya kwamba umeme juu, moja katika binary, ili kuzungumza, au kugeuka

284
00:16:22,600 --> 00:16:24,290
kwamba umeme mbali.

285
00:16:24,290 --> 00:16:26,210
>> Hivyo Barry, kama ingekuwa si akili, inaweza sisi dim taa

286
00:16:26,210 --> 00:16:28,140
kikamilifu kwa muda tu?

287
00:16:28,140 --> 00:16:31,750
Hii hapa ni sana gratuitous binary sifuri.

288
00:16:31,750 --> 00:16:35,960
Haki zote kama tukikataa taa nyuma juu, sasa Sanders Theatre ni

289
00:16:35,960 --> 00:16:37,990
anayewakilisha thamani binary ya moja.

290
00:16:37,990 --> 00:16:41,860
Kwa bahati mbaya, na kidogo tu moja, pamoja na kuweka moja tu ya taa, tunaweza tu

291
00:16:41,860 --> 00:16:45,770
kuwakilisha nambari mbili katika dunia, sifuri na moja, na ni d kuwa nzuri kama

292
00:16:45,770 --> 00:16:48,510
kompyuta inaweza kuhesabu kidogo juu ya hilo, lakini kwa hakika, wanaweza.

293
00:16:48,510 --> 00:16:52,170
Hivyo basi mimi kuvuta juu ya screen hapa rafiki yetu, Nate Hardison, ni nani atakayewakabidhi

294
00:16:52,170 --> 00:16:54,980
sisi kuangalia haraka katika kipindi cha dakika chache tu katika

295
00:16:54,980 --> 00:16:56,505
hii dhana ya binary.

296
00:17:03,526 --> 00:17:06,550
>> Nate HARDISON: Nyuma wakati wewe kujifunza jinsi ya kusoma na kuandika namba, wewe

297
00:17:06,550 --> 00:17:10,589
kujifunza kuhusu tarakimu sifuri na tisa.

298
00:17:10,589 --> 00:17:13,589
Kuandika idadi kubwa kuliko yote tisa, wewe kujifunza kwamba wote mnatakiwa kufanya

299
00:17:13,589 --> 00:17:23,130
ilikuwa kutumia baadhi ya macho ya tarakimu hizi, kama katika 52 na 437.

300
00:17:23,130 --> 00:17:27,760
Hivyo njia hii ya kuandika namba ina jina, decimal nukuu.

301
00:17:27,760 --> 00:17:28,830
Mbona decimal?

302
00:17:28,830 --> 00:17:33,630
Naam, mizizi ya Kilatini ya decimal, Deca, maana yake 10, na wakati una tarakimu 10

303
00:17:33,630 --> 00:17:37,420
katika nukuu mfumo wako, 10 inakuwa idadi badala maalum.

304
00:17:37,420 --> 00:17:42,480
Hebu tuangalie idadi 437 yaliyoandikwa katika nukuu decimal kuelewa kwa nini.

305
00:17:42,480 --> 00:17:52,330
>> Tunaweza kwanza kuvunja 437 400 plus 30 katika plus 7.

306
00:17:52,330 --> 00:18:00,260
Tunaweza kuchukua ni mbali hata zaidi, hivyo kwamba sisi tumepewa mara nne 100 plus 3

307
00:18:00,260 --> 00:18:05,120
mara 10 plus mara 7 1.

308
00:18:05,120 --> 00:18:08,580
kumbuka kujifunza kuhusu mahali ndio, mahali 10s, 100s

309
00:18:08,580 --> 00:18:10,190
mahali, na kadhalika?

310
00:18:10,190 --> 00:18:13,120
Hii ni hasa ambapo kwamba linatokana.

311
00:18:13,120 --> 00:18:15,870
Na hatimaye, tunaweza kuona jinsi sisi tumepewa rundo la nguvu za

312
00:18:15,870 --> 00:18:17,900
10 iliyoingia katika hapa.

313
00:18:17,900 --> 00:18:28,820
Sisi tumepewa mara 4 10-2 plus mara 3 10-1 plus 7

314
00:18:28,820 --> 00:18:31,720
mara 10 kwa sifuri.

315
00:18:31,720 --> 00:18:35,390
Hivyo sasa unaweza kuona kwa nini 10 ni idadi maalum katika nukuu decimal.

316
00:18:35,390 --> 00:18:37,370
Kwa kweli, sisi tumepewa jina kwa ajili yake.

317
00:18:37,370 --> 00:18:40,420
Ni wito wa msingi, tangu ni msingi wa exponent katika

318
00:18:40,420 --> 00:18:42,100
hesabu zetu hapa.

319
00:18:42,100 --> 00:18:45,320
>> Nukuu decimal si njia pekee ya kuwakilisha idadi.

320
00:18:45,320 --> 00:18:50,480
Kwa kweli, hata kama sisi kujikwamua tarakimu mbili kwa njia ya tisa, tunaweza bado

321
00:18:50,480 --> 00:18:53,740
kuwakilisha yote ya namba ambazo tunaweza pamoja na decimal.

322
00:18:53,740 --> 00:18:58,910
Hivyo sasa kwamba tuna tarakimu mbili, sifuri na moja, mbili ni idadi yetu wa pekee,

323
00:18:58,910 --> 00:19:01,210
msingi wa nukuu mfumo wetu.

324
00:19:01,210 --> 00:19:04,580
jina la mfumo huu nukuu inaitwa binary, tangu

325
00:19:04,580 --> 00:19:07,030
kiambishi awali bi maana mbili.

326
00:19:07,030 --> 00:19:11,190
Hivyo badala yake, sasa, ya kuwa mahali ndio, na 10s mahali, na kadhalika, sisi

327
00:19:11,190 --> 00:19:15,900
sasa wana nafasi ndio, mahali wawiliwawili, mahali fours, na kadhalika, kwenda kwa

328
00:19:15,900 --> 00:19:17,550
mamlaka ya mbili.

329
00:19:17,550 --> 00:19:19,450
Basi hebu angalia hili na kufanya baadhi ya kuhesabu kura.

330
00:19:19,450 --> 00:19:24,940
Hivyo ni sifuri sifuri bado, na moja bado ni moja.

331
00:19:24,940 --> 00:19:31,050
Hata hivyo, sasa kwamba sisi tumepewa mahali wawili-wawili badala ya mahali 10s, 10

332
00:19:31,050 --> 00:19:33,190
inawakilisha namba mbili.

333
00:19:33,190 --> 00:19:38,386
Ili kupata tatu, sisi kuongeza moja na kwamba, na kupata 11.

334
00:19:38,386 --> 00:19:44,660
Nne, tangu sasa kuna mahali fours, ni kuwakilishwa na 100.

335
00:19:44,660 --> 00:19:49,410
Tano ni 101.

336
00:19:49,410 --> 00:19:53,642
Sita ni 110.

337
00:19:53,642 --> 00:19:56,610
Saba ni 111.

338
00:19:56,610 --> 00:19:58,470
Nane, tena, ina nafasi yake mwenyewe.

339
00:19:58,470 --> 00:20:02,790
Hivyo ni 1000.

340
00:20:02,790 --> 00:20:05,201
Na nadhani wewe kupata uhakika.

341
00:20:05,201 --> 00:20:09,800
>> SPIKA 1: Hivyo hii ni kusema nini kompyuta kufanya na nini ni binary ni

342
00:20:09,800 --> 00:20:13,690
kweli si tofauti kutoka nini tumekuwa kuchukua kwa nafasi kwa baadhi ya

343
00:20:13,690 --> 00:20:14,560
miaka, sawa?

344
00:20:14,560 --> 00:20:17,097
Nyuma katika shule ya daraja, wewe kujifunza kuhesabu kwa usahihi katika

345
00:20:17,097 --> 00:20:19,970
mtindo kwamba Nate mapendekezo, lakini pengine si kweli mawazo kuhusu

346
00:20:19,970 --> 00:20:22,440
hayo tangu, ukweli kwamba kuna mahali hapa ndio, 10s mahali, na 100s

347
00:20:22,440 --> 00:20:23,315
mahali, na kwamba pretty holela.

348
00:20:23,315 --> 00:20:26,210
Na hakika, tu kutumia kompyuta hii ya msingi tofauti.

349
00:20:26,210 --> 00:20:30,160
Lakini mwisho wa siku, kwa kweli kimwili kuwakilisha wazo hili la

350
00:20:30,160 --> 00:20:33,130
sifuri na moja, wewe ni wazi si tu kugeuka taa na mbali

351
00:20:33,130 --> 00:20:33,445
lazima.

352
00:20:33,445 --> 00:20:36,100
Wewe haja ya kufanya hivyo kwa kiwango cha finer nafaka.

353
00:20:36,100 --> 00:20:39,990
Na kwa nafaka finer, unaweza kukumbuka hii silly kidogo toy kutoka utotoni,

354
00:20:39,990 --> 00:20:42,570
Woolly Willy na hawa wadogo chembe magnetic.

355
00:20:42,570 --> 00:20:46,440
>> Hivyo magnetic chembe ni kitu ambacho unaweza align katika michache ya

356
00:20:46,440 --> 00:20:49,920
tofauti maelekezo, labda kaskazini-kusini au kaskazini-kusini.

357
00:20:49,920 --> 00:20:53,470
Na hivyo mengi ya incarnations kimwili ya teknolojia ya siku hizi ya kwamba matumizi ya

358
00:20:53,470 --> 00:20:57,690
binary, kwamba matumizi zeros na ndio, tu kuwa magnetism ndani

359
00:20:57,690 --> 00:21:04,110
kwamba aligns mambo juu-chini au chini-juu, na hivyo kuwakilisha zero au moja,

360
00:21:04,110 --> 00:21:04,890
mtiririko huo.

361
00:21:04,890 --> 00:21:08,930
Hivyo kweli, hebu kuondokana na abstract hapa, na kuangalia ndani ya

362
00:21:08,930 --> 00:21:10,780
ya nini zaidi jadi kompyuta gari ngumu.

363
00:21:10,780 --> 00:21:13,840
Hii moja hutokea kuwa kubwa kidogo kwenye screen, kwa kuwa ni kutoka desktop

364
00:21:13,840 --> 00:21:18,310
kompyuta, lakini Laptops leo bado tuna teknolojia hii moja, lakini ni hatua kwa hatua

365
00:21:18,310 --> 00:21:22,140
kuwa kubadilishwa kwa mambo ya kisasa zaidi ambayo kweli hakuna kusonga

366
00:21:22,140 --> 00:21:25,275
sehemu - ndani ya basi, ya gari ngumu.

367
00:21:25,275 --> 00:21:28,450
>> SPIKA 2: gari ngumu ni ambapo PC yako maduka zaidi ya

368
00:21:28,450 --> 00:21:29,990
data ya kudumu.

369
00:21:29,990 --> 00:21:34,710
Ili kufanya hivyo, data husafiri kutoka RAM pamoja na programu ya ishara ya kwamba kuwaambia

370
00:21:34,710 --> 00:21:37,420
gari ngumu jinsi ya kuhifadhi data hizo.

371
00:21:37,420 --> 00:21:40,720
ngumu kuendesha nyaya kutafsiri ishara wale katika voltage

372
00:21:40,720 --> 00:21:42,270
kushuka.

373
00:21:42,270 --> 00:21:46,290
Haya, kwa upande wake, kudhibiti gari ngumu ya sehemu kusonga, baadhi ya wachache

374
00:21:46,290 --> 00:21:48,890
kusonga sehemu kushoto katika kompyuta ya kisasa.

375
00:21:48,890 --> 00:21:53,400
Baadhi ya ishara kudhibiti motor, shule ya chuma ambayo coated platters.

376
00:21:53,400 --> 00:21:56,810
Data zako ni kweli kuhifadhiwa kwenye platters hizi.

377
00:21:56,810 --> 00:21:59,940
Ishara nyingine hoja vichwa kusoma kuandika kusoma au

378
00:21:59,940 --> 00:22:02,030
kuandika data kwenye platters.

379
00:22:02,030 --> 00:22:06,710
Mashine Hii ni sahihi kwamba nywele za binadamu hakuweza hata kupita kati ya

380
00:22:06,710 --> 00:22:11,390
wakuu wa platters inazunguka, lakini wote kazi kwa kasi kali.

381
00:22:11,390 --> 00:22:15,120
>> SPIKA 1: Hivyo sisi sasa zoom katika juu ya kile kinachotokea kweli juu ya haya

382
00:22:15,120 --> 00:22:19,620
platters katika suala la magnetism, tuna hii ya pili ya inaonekana mbili.

383
00:22:19,620 --> 00:22:22,940
>> SPIKA 3: Hebu kuangalia nini sisi niliona tu katika mwendo wa polepole.

384
00:22:22,940 --> 00:22:27,010
Wakati Pulse mafupi ya umeme ni alimtuma kichwa kusoma-kuandika, ni flips

385
00:22:27,010 --> 00:22:30,390
juu ya sumakuumeme vidogo kwa sehemu ya pili.

386
00:22:30,390 --> 00:22:34,280
sumaku inajenga uwanja, ambayo inabadilisha polarity wa vidogo, vidogo

387
00:22:34,280 --> 00:22:37,995
sehemu ya chembe chuma ambayo kanzu uso kila sahani ya.

388
00:22:37,995 --> 00:22:41,810
mfululizo mfano wa maeneo haya vidogo kushtakiwa hadi kwenye disk inawakilisha

389
00:22:41,810 --> 00:22:45,820
moja kidogo ya data katika mfumo binary idadi kutumiwa na kompyuta.

390
00:22:45,820 --> 00:22:49,430
Sasa kama sasa ni alimtuma njia moja kwa njia ya kichwa kusoma-kuandika, eneo

391
00:22:49,430 --> 00:22:51,170
ni polarized katika mwelekeo mmoja.

392
00:22:51,170 --> 00:22:53,250
Kama sasa ni alimtuma katika mwelekeo kinyume,

393
00:22:53,250 --> 00:22:55,220
ubaguzi ni kuachwa.

394
00:22:55,220 --> 00:22:57,680
Jinsi gani unaweza kupata data mbali disk ngumu?

395
00:22:57,680 --> 00:22:59,400
Tu kubadili mchakato.

396
00:22:59,400 --> 00:23:02,050
Hivyo ni chembe kwenye disk kwamba kupata sasa na kusoma-kuandika

397
00:23:02,050 --> 00:23:03,340
kichwa kusonga mbele.

398
00:23:03,340 --> 00:23:06,010
Kuweka pamoja mamilioni ya makundi haya sumaku, na

399
00:23:06,010 --> 00:23:07,440
nimepata faili.

400
00:23:07,440 --> 00:23:12,240
Sasa vipande vya faili moja inaweza kutawanyika kila platters gari ya,

401
00:23:12,240 --> 00:23:15,270
aina ya kama fujo ya magazeti juu ya dawati yako.

402
00:23:15,270 --> 00:23:18,800
Hivyo maalum faili ziada anaendelea kufuatilia kwa ambako kila kitu ni.

403
00:23:18,800 --> 00:23:21,640
Je, si wewe unataka alikuwa na kitu kama hicho?

404
00:23:21,640 --> 00:23:23,340
>> SPIKA 1: Kweli kweli.

405
00:23:23,340 --> 00:23:27,560
Hivyo tuna uwezo huu wa kuwakilisha taarifa hii idadi,

406
00:23:27,560 --> 00:23:28,440
katika ngazi ya chini sana.

407
00:23:28,440 --> 00:23:32,730
Tuna njia ya kimwili ya anayewakilisha kwamba kitu kimoja, lakini hatuwezi kwa kweli

408
00:23:32,730 --> 00:23:36,440
kufanya yote kwamba mengi ya riba bado, zaidi labda arithmetic baadhi na

409
00:23:36,440 --> 00:23:36,940
hisabati.

410
00:23:36,940 --> 00:23:40,830
Sisi hatuna njia ya kuwakilisha mambo hivi sasa kama barua ya alfabeti,

411
00:23:40,830 --> 00:23:44,100
ili sisi binadamu wanaweza kuwasiliana, kwa kutumia vifaa hivi sawa.

412
00:23:44,100 --> 00:23:48,240
Lakini nashiriki, kuna encodings, mifumo ya zeros na wale

413
00:23:48,240 --> 00:23:52,920
kwamba kuwakilisha constructs ngazi za juu kama, na B, na C, na nzima

414
00:23:52,920 --> 00:23:54,880
sentensi, na aya, na kama.

415
00:23:54,880 --> 00:24:00,300
Na hivyo ASCII, ambayo ni kifupi kwamba inahusu mfumo huu coding ambapo

416
00:24:00,300 --> 00:24:04,350
namba moja inawakilisha barua aliyopewa - kwa mfano, idadi ambayo tunajua

417
00:24:04,350 --> 00:24:09,120
kama thamani decimal 65 inajulikana kama barua mtaji wa kompyuta.

418
00:24:09,120 --> 00:24:13,670
thamani decimal ya 97 katika kompyuta inajulikana kama a lowercase.

419
00:24:13,670 --> 00:24:15,210
Na nini kwamba kweli maana?

420
00:24:15,210 --> 00:24:19,510
Naam, hata ingawa Nate, wakati iliyopita, hesabiwa kutoka sifuri hadi nane, ikiwa

421
00:24:19,510 --> 00:24:24,910
tulikuwa kuendelea kuhesabu hadi 65, au zaidi, hadi 97, muundo wa

422
00:24:24,910 --> 00:24:28,440
zeros na wale ambao angekuwa inayotolewa kwenye screen itakuwa hasa

423
00:24:28,440 --> 00:24:33,420
kile kompyuta hutumia kuwakilisha barua katika kofia wote, au barua

424
00:24:33,420 --> 00:24:34,610
katika lowercase.

425
00:24:34,610 --> 00:24:36,690
Na kwa kweli, kuna mpango mzima huu.

426
00:24:36,690 --> 00:24:41,570
Hii ni, katika mtazamo wa kwanza, balaa chati ya encodings, lakini kama wewe kuzingatia

427
00:24:41,570 --> 00:24:46,210
tu juu ya nusu haki hapa, taarifa katika safu hii ya katikati, tuna huu

428
00:24:46,210 --> 00:24:49,010
dhana ya idadi ikifuatiwa na barua.

429
00:24:49,010 --> 00:24:53,830
Na saa ya juu, tuna 32, na Char tabia, ambayo 32,

430
00:24:53,830 --> 00:24:57,360
integer, sasa inahusu, inaonekana bar nafasi tabia.

431
00:24:57,360 --> 00:25:00,720
Baada ya kupata nafasi bar tabia juu ya Laptop yako, nini wewe ni kweli

432
00:25:00,720 --> 00:25:04,160
kutuma ni idadi, mfano wa zeros na ndio, mtiririko wa umeme,

433
00:25:04,160 --> 00:25:07,770
kama wewe, anayewakilisha zeros hizo na zile, kwamba kompyuta kisha

434
00:25:07,770 --> 00:25:10,330
anatafsiri kama tabia nafasi kwenye screen.

435
00:25:10,330 --> 00:25:12,210
uhakika Moderators ni 33.

436
00:25:12,210 --> 00:25:13,345
Quotes Double ni 34.

437
00:25:13,345 --> 00:25:18,945
Na kama sisi kitabu chini hapa juu ya haki, tunaona kwamba 65 ni kweli, na

438
00:25:18,945 --> 00:25:21,290
97 Hakika ni Herufi za chini.

439
00:25:21,290 --> 00:25:23,910
>> Hivyo sasa kwamba tuna mpango huu encoding, tunaweza kuanza kwa

440
00:25:23,910 --> 00:25:25,080
Spell mambo ya nje.

441
00:25:25,080 --> 00:25:30,170
Hakika, kompyuta kawaida kujieleza katika vitengo kiwango, si

442
00:25:30,170 --> 00:25:33,020
kutumia kidogo ya mtu binafsi, ambayo tena, si yote muhimu tu

443
00:25:33,020 --> 00:25:36,600
kuwakilisha zero au moja taa, juu au mbali, lakini badala yake, kwa kutumia

444
00:25:36,600 --> 00:25:37,530
Mwandamano wa bits.

445
00:25:37,530 --> 00:25:40,100
Na kitengo cha kawaida zaidi ya kipimo, kama pengine kujua, au angalau

446
00:25:40,100 --> 00:25:41,810
inferred, ni Byte.

447
00:25:41,810 --> 00:25:45,960
Byte ni nane tu bits, zeroes nane au ndio katika mstari.

448
00:25:45,960 --> 00:25:48,090
Hivyo tunaweza kuanza kuzungumzia mambo ya nje.

449
00:25:48,090 --> 00:25:52,580
Na hivyo kama tunaweza, kwa nini kujaribu hii kidogo kidogo pamoja hapa?

450
00:25:52,580 --> 00:25:55,670
Je, kuna watu nane katika chumba hiki ambao wangekuwa tayari

451
00:25:55,670 --> 00:25:56,870
kuja kwenye hatua?

452
00:25:56,870 --> 00:26:00,880
Wewe kuwa starehe ya kuonekana kwenye kamera, lakini wewe si kweli wanahitaji

453
00:26:00,880 --> 00:26:03,690
kujua vinginevyo nini kinaendelea bado tu.

454
00:26:03,690 --> 00:26:07,240
Mimi naona mtu mmoja kuwa alijitolea zaidi ya hapa.

455
00:26:07,240 --> 00:26:18,380
Mbili, tatu, nne, tano, sita, saba, na vipi kuhusu nane?

456
00:26:18,380 --> 00:26:18,920
Kuja juu juu.

457
00:26:18,920 --> 00:26:22,550
>> Hivyo wewe ni kuhusu kuwakilisha Byte ya watu.

458
00:26:22,550 --> 00:26:30,190
Hebu umekuwa mahali 128s, wewe mahali 64s, 32s wewe mahali.

459
00:26:30,190 --> 00:26:32,720
Lakini sisi ni kwenda kwa haraka sana na kwa reverse hii.

460
00:26:32,720 --> 00:26:35,170
Hivyo basi mimi kukutana na wewe wote pale.

461
00:26:35,170 --> 00:26:39,840
Na unapaswa kuwa katika nafasi ya 128s njia yote juu, hapa kiasi kama

462
00:26:39,840 --> 00:26:43,080
mamia mahali au mahali maelfu itakuwa mbali zaidi kwa upande wa kushoto, tunataka

463
00:26:43,080 --> 00:26:45,740
placeholder kubwa kuwa hapa juu ya kushoto kama vile.

464
00:26:45,740 --> 00:26:55,230
Tuna 64s, 32 16S, 8s, 4s, 2S, na 1s -

465
00:26:55,230 --> 00:26:56,030
bora.

466
00:26:56,030 --> 00:26:58,100
Hivyo basi, tuna -

467
00:26:58,100 --> 00:27:00,190
sawa, unaweza kunisaidia.

468
00:27:00,190 --> 00:27:01,890
Hivyo basi, tuna - nini jina lako?

469
00:27:01,890 --> 00:27:02,560
Joanne: Joanne.

470
00:27:02,560 --> 00:27:06,240
SPIKA 1: Basi Joanne na mimi sasa kwenda kushauri guys haya juu ya jinsi sisi

471
00:27:06,240 --> 00:27:07,850
unaweza kwenda katika kuendeleza kitu nje.

472
00:27:07,850 --> 00:27:10,640
Hivyo juu ya migongo ya shuka yao ya karatasi, wana kidogo kudanganya karatasi

473
00:27:10,640 --> 00:27:14,720
ambayo inaenda kuwaambia kama walikuwa anayewakilisha zero au moja.

474
00:27:14,720 --> 00:27:18,000
Na kwa nini, kwa unyenyekevu, tutaweza kuwakilisha sifuri na tu

475
00:27:18,000 --> 00:27:19,580
amesimama awkwardly.

476
00:27:19,580 --> 00:27:20,360
Nzuri sana.

477
00:27:20,360 --> 00:27:24,200
Au moja kwa kuongeza mkono wako, anayewakilisha moja.

478
00:27:24,200 --> 00:27:28,380
Na hebu angalia kama hatuwezi Spell nje nne tabia maneno hapa.

479
00:27:28,380 --> 00:27:33,870
>> Hivyo kwenda mbele sasa, kujitolea, na nitafanya moja pande zote kwa kuongeza mkono wako

480
00:27:33,870 --> 00:27:38,940
kama wewe ni mmoja, au kuweka chini kama wewe ni sifuri.

481
00:27:38,940 --> 00:27:45,550
Hivyo sasa kwamba tuna mikono hizi tatu, kitu ambacho idadi, kila mtu mwingine, ni

482
00:27:45,550 --> 00:27:47,800
wao alimwakilisha?

483
00:27:47,800 --> 00:27:48,760
Okay, 67.

484
00:27:48,760 --> 00:27:49,040
Kwa nini?

485
00:27:49,040 --> 00:27:49,970
Naam, sanity haraka kuangalia.

486
00:27:49,970 --> 00:27:51,910
Mahali 64s, kwa sababu ni moja.

487
00:27:51,910 --> 00:27:58,870
Hiyo ni kama mara moja 64, pamoja mara mbili 1, hivyo ndiyo 66, plus 1 mara 1.

488
00:27:58,870 --> 00:28:00,610
Hiyo ni pamoja na 1, hivyo 67.

489
00:28:00,610 --> 00:28:03,740
Hivyo sasa guys hawa ni pamoja anayewakilisha 67, ambayo inaonekana

490
00:28:03,740 --> 00:28:06,240
inawakilisha nini hapa katika ASCII?

491
00:28:06,240 --> 00:28:06,510
Okay,

492
00:28:06,510 --> 00:28:07,650
hivyo C. zote haki.

493
00:28:07,650 --> 00:28:09,530
Hivyo sasa hebu kuendelea kwa pande zote mbili.

494
00:28:09,530 --> 00:28:12,735
Kila mtu kwa kuanzia na mikono yao chini, na kisha pande zote mbili.

495
00:28:12,735 --> 00:28:15,260
Kweli, kuna si mengi ya jukumu hapa, nadhani, lakini tutaweza kujifanya.

496
00:28:15,260 --> 00:28:19,820
Hivyo pande zote mbili, kuongeza au kupunguza mikono yako.

497
00:28:19,820 --> 00:28:20,530
>> Wote haki.

498
00:28:20,530 --> 00:28:23,230
Watazamaji, sisi ni nani sasa?

499
00:28:23,230 --> 00:28:24,860
Kuelezea ni 83.

500
00:28:24,860 --> 00:28:26,050
Hivyo unaweza kufanya hisabati.

501
00:28:26,050 --> 00:28:29,810
Lakini kwa mtu yeyote ambaye ni mkono up, wewe kuongeza katika idadi ya kwamba wao kuwakilisha.

502
00:28:29,810 --> 00:28:31,610
Hivyo basi, tuna 83.

503
00:28:31,610 --> 00:28:36,510
Hebu kupanua karatasi ya kudanganya kidogo, na sisi sasa kuwa na -

504
00:28:36,510 --> 00:28:38,890
hii inaweza kuwa dhahiri ambapo tunakwenda hapa, lakini

505
00:28:38,890 --> 00:28:42,220
hata hivyo, pande zote tatu.

506
00:28:42,220 --> 00:28:45,870
Okay, pande zote tatu ni vizuri kwenda chini huko, ili pande zote tatu, kile ni idadi

507
00:28:45,870 --> 00:28:47,120
haya guys sasa anayewakilisha?

508
00:28:50,090 --> 00:28:56,690
Okay, nikasikia 53, ambayo sasa inawakilisha - ya kuvutia.

509
00:28:56,690 --> 00:29:00,770
Sasa kwa nini hii aina ya matokeo counter-angavu, haki?

510
00:29:00,770 --> 00:29:02,910
Kama tunataka kuwakilisha tano -

511
00:29:02,910 --> 00:29:03,900
sisi wote pengine kujua ambapo hii ni kwenda -

512
00:29:03,900 --> 00:29:07,360
nini si mimi tu kuongeza nafasi fours na mahali ndio?

513
00:29:07,360 --> 00:29:10,060
>> Naam, tunatambua kwamba kuna tofauti, kimsingi, kati ya jinsi

514
00:29:10,060 --> 00:29:11,760
kompyuta anatafsiri bits haya.

515
00:29:11,760 --> 00:29:15,470
Kama wewe ni kujaribu kuwakilisha namba tano, kisha kabisa, sisi tu

516
00:29:15,470 --> 00:29:18,330
kunyanyua mkono wako namba nne na kuinua mkono namba moja.

517
00:29:18,330 --> 00:29:20,010
Lakini sisi siyo anayewakilisha namba hapa.

518
00:29:20,010 --> 00:29:23,690
muktadha hapa juu ya hatua ni kwamba sisi ni anayewakilisha wahusika au

519
00:29:23,690 --> 00:29:28,110
chars, na kwa mantiki hii, kompyuta ina kutambua kwamba oh, hii

520
00:29:28,110 --> 00:29:30,720
mfano wa sarafu ni si idadi peke yake.

521
00:29:30,720 --> 00:29:33,210
Ni kweli anayewakilisha ngazi ya juu ya dhana.

522
00:29:33,210 --> 00:29:35,010
Katika kesi hiyo, barua alfabeti.

523
00:29:35,010 --> 00:29:38,820
Hivyo ukweli kwamba ni sasa anayewakilisha namba tano na

524
00:29:38,820 --> 00:29:44,290
thamani 53 ni kwa sababu katika ASCII, kitu sisi aesthetically kuona kama

525
00:29:44,290 --> 00:29:48,200
namba tano yenyewe inahitaji muundo wa bits - kwa sababu kwa nini?

526
00:29:48,200 --> 00:29:51,310
Naam, ulimwengu tu aliamua kutumia idadi ya chini, sifuri, moja, mbili,

527
00:29:51,310 --> 00:29:54,130
tatu kwa nini inaonekana kuwa uungwana cryptic mambo.

528
00:29:54,130 --> 00:29:56,830
Na kwa kweli, hizi ni wahusika kuwa ni si kwenye keyboard.

529
00:29:56,830 --> 00:30:00,330
Maalum misemo ambayo unahitaji katika kompyuta ya kufanya mambo ya kuvutia, lakini

530
00:30:00,330 --> 00:30:02,010
binadamu kweli kamwe aina yao.

531
00:30:02,010 --> 00:30:04,220
Hivyo 53, kwa hakika, inawakilisha tano.

532
00:30:04,220 --> 00:30:10,460
Sasa tu kama hundi ya mwisho sanity, nini idadi lazima wao

533
00:30:10,460 --> 00:30:12,880
kuwakilisha katika muda tu?

534
00:30:12,880 --> 00:30:14,060
Sawa, hivyo 48.

535
00:30:14,060 --> 00:30:15,720
Na kwa kweli, kwenda mbele, pande zote nne.

536
00:30:18,650 --> 00:30:22,680
16 plus 32 ni kweli 48.

537
00:30:22,680 --> 00:30:26,510
Na hivyo duru kubwa ya applause, kama tunaweza, kwa kujitolea yetu nane hapa.

538
00:30:31,410 --> 00:30:32,660
Vizuri sana kufanyika.

539
00:30:35,290 --> 00:30:36,490
Mwelekeo wowote ni faini.

540
00:30:36,490 --> 00:30:41,050
>> Hivyo sisi sasa kuwa na njia si tu wa kufikiri kuhusu jinsi ya kuwakilisha data,

541
00:30:41,050 --> 00:30:44,120
na kwa kweli ni anayewakilisha kimwili, lakini pia kufanya juu

542
00:30:44,120 --> 00:30:45,710
ngazi ya juu ya mambo.

543
00:30:45,710 --> 00:30:48,430
Na hakika, hii itakuwa ni mandhari katika sayansi ya kompyuta ya

544
00:30:48,430 --> 00:30:52,410
kujenga mambo zaidi na zaidi ya kuvutia na tata juu ya

545
00:30:52,410 --> 00:30:54,030
haki rahisi mawazo -

546
00:30:54,030 --> 00:30:56,170
katika kesi hii, tu zeros na ndio.

547
00:30:56,170 --> 00:31:00,120
Katika suala la nini hii ni muhimu, vizuri, hata kama katika shaka kama hii,

548
00:31:00,120 --> 00:31:03,810
tutaweza kuzingatia misingi, na juu ya programu, na juu ya kutatua ya

549
00:31:03,810 --> 00:31:07,050
matatizo, unaweza kwenda mbali katika sayansi ya kompyuta katika idadi yoyote ya maelekezo.

550
00:31:07,050 --> 00:31:10,950
Katika kesi hii hapa, hii ni chati kwamba una katika ukurasa wa nyuma wa yako

551
00:31:10,950 --> 00:31:14,580
unofficial mwongozo wa CS katika Harvard, mmoja wa nakala zake leo mbili.

552
00:31:14,580 --> 00:31:17,450
Hii inaonyesha wengi mwelekeo tofauti ambazo unaweza kwenda baada ya

553
00:31:17,450 --> 00:31:18,400
Bila shaka kama hii -

554
00:31:18,400 --> 00:31:21,530
kujifunza kuhusu akili bandia, kuhusu graphics, kuhusu

555
00:31:21,530 --> 00:31:24,370
mashine kujifunza, kuhusu lugha yenyewe.

556
00:31:24,370 --> 00:31:26,410
Kutambua, pia kwamba kuna bado njia nyingine.

557
00:31:26,410 --> 00:31:28,670
Kuna njia zaidi ya hisabati katika sayansi ya kompyuta.

558
00:31:28,670 --> 00:31:31,740
Kama huna hata uwezo wa kuchukua kitu kama CS50 hii kuanguka, kuna

559
00:31:31,740 --> 00:31:35,070
utangulizi kozi katika spring, Sayansi ya Kompyuta 1, kwa mfano, ni

560
00:31:35,070 --> 00:31:38,050
lakini mwingine juu ya-njia panda ya dunia hii mpya.

561
00:31:38,050 --> 00:31:41,600
>> Sasa kama kando, kwa maslahi ya kutatua matatizo ya kuhusiana na kozi,

562
00:31:41,600 --> 00:31:46,050
kutambua CS50 kuweka nje baadhi ya wakati uliopita ili kujaribu kutatua moja ya matatizo haya,

563
00:31:46,050 --> 00:31:49,640
tatizo inayojulikana kama my.harvard, ambayo wengi wa unaweza kutumia kwa kweli

564
00:31:49,640 --> 00:31:54,040
duka kwa kozi, lakini kama si, angalia chombo kama hiki, kama vile wengine

565
00:31:54,040 --> 00:31:57,800
wazao kwamba baadhi ya wanafunzi wetu wa zamani na wafanyakazi waumba.

566
00:31:57,800 --> 00:32:00,770
Lakini katika Kozi Harvard, ambayo ni chombo mtandao msingi, kitu ambacho

567
00:32:00,770 --> 00:32:05,510
itakuwa na uwezo wa kubuni na kupeleka wenyewe, kama vile bado

568
00:32:05,510 --> 00:32:09,210
mambo mengine kama vizuri na mwisho wa muhula, kutambua kwamba hii hujenga

569
00:32:09,210 --> 00:32:10,590
juu ya kuweka wazi data.

570
00:32:10,590 --> 00:32:13,490
Katika kesi hii, bila shaka, catalog, na inaruhusu wanafunzi katika kesi hii kwa

571
00:32:13,490 --> 00:32:16,320
kuchunguza data uungwana tata ya kuweka.

572
00:32:16,320 --> 00:32:19,495
>> Sisi akachimba up jana usiku takwimu chache msingi folks chache elfu ambao

573
00:32:19,495 --> 00:32:21,530
wamekuwa kutumia hii zaidi ya siku chache zilizopita.

574
00:32:21,530 --> 00:32:25,260
Kama tumekuwa curious kujua jinsi wengi kozi rafiki yako kweli

575
00:32:25,260 --> 00:32:29,720
huwa na duka, vizuri, leo data hii inapendekeza kwamba 7.6 ni wastani

576
00:32:29,720 --> 00:32:32,610
idadi ya kozi juu ya ununuzi orodha ya mtu.

577
00:32:32,610 --> 00:32:36,350
Na sasa mimi nitakupa pia statistic ya idadi kubwa ya

578
00:32:36,350 --> 00:32:39,550
kozi juu ya ununuzi orodha ya mtu - na sisi sote pengine kujua

579
00:32:39,550 --> 00:32:40,800
mtu kama hii.

580
00:32:43,820 --> 00:32:46,740
201 ni rekodi ya mwaka huu.

581
00:32:46,740 --> 00:32:52,320
Sasa baadhi ya wanafunzi wetu wa zamani na wafanyakazi kweli kuweka pamoja picha ya video kwa

582
00:32:52,320 --> 00:32:55,560
kuchora picha kwa ajili yenu ya njia gani hii ya sayansi ya kompyuta

583
00:32:55,560 --> 00:32:57,360
na CS50 yenyewe ni.

584
00:32:57,360 --> 00:33:02,060
Hebu kwenda mbele na kuvuta, shukrani kwa Mheshimiwa Harvahd hapa, video zinazozalishwa na

585
00:33:02,060 --> 00:33:06,825
baadhi ya watangulizi wako, kama tunaweza kuweka taa kwa ajili hii.

586
00:33:10,980 --> 00:35:39,126
[MUSIC kucheza]

587
00:35:39,126 --> 00:35:42,630
>> SPIKA 1: Mimi nilikuwa na wazo kwamba alikuwa anaenda kutokea.

588
00:35:42,630 --> 00:35:46,170
Basi angalia mbaya zaidi katika kile uongo mbele.

589
00:35:46,170 --> 00:35:49,060
Hivyo katika suala la matarajio ya kozi hii, wewe ni kweli inatarajiwa

590
00:35:49,060 --> 00:35:52,817
kuhudhuria au kuangalia hotuba ya shaka, kuwasilisha seti tatizo nane, kuchukua mbili

591
00:35:52,817 --> 00:35:54,720
Quizzes, kuwasilisha mradi wa mwisho.

592
00:35:54,720 --> 00:35:58,640
Katika suala la darasa, kutambua kwamba maoni yangu katika ufunguzi kuhusu

593
00:35:58,640 --> 00:36:02,380
kupitisha-kushindwa, kitu ambacho sisi sana kuchukua kwa moyo katika CS50 - hakuna

594
00:36:02,380 --> 00:36:05,110
karibu kutosha ya utamaduni katika Harvard ya kujaribu

595
00:36:05,110 --> 00:36:07,080
kitu na kuhatarisha kushindwa.

596
00:36:07,080 --> 00:36:09,870
Hakika, tulikuwa na idadi ya wanafunzi, na mwenyewe hasa, ambaye alikuwa

597
00:36:09,870 --> 00:36:15,310
wasiwasi kuhusu kuumiza GPA yako, au kupata B katika kitu kama CS50,

598
00:36:15,310 --> 00:36:19,222
na fursa ya kuchukua kozi kama hii na kozi nyingine gateway katika

599
00:36:19,222 --> 00:36:23,950
ngazi ya utangulizi kupita / kushindwa ni nafasi sana isiyotumika vizuri katika hii

600
00:36:23,950 --> 00:36:24,740
chuo kwa ujumla.

601
00:36:24,740 --> 00:36:29,750
Na hivyo tafadhali kujua, hata mimi waliojiunga katika kozi hii ya awali kwa ajili ya kupita / kushindwa

602
00:36:29,750 --> 00:36:32,840
mikopo peke yake, na hata kama mimi kubadili mwisho wa siku, ilikuwa

603
00:36:32,840 --> 00:36:36,170
wale wiki tano ya awali, hadi Jumatatu ya tano ya muhula, ambayo ni

604
00:36:36,170 --> 00:36:39,700
cutoff, kwamba kuruhusiwa yangu kweli kuweka mguu ndani ya hizi mpya

605
00:36:39,700 --> 00:36:43,660
maji, na kwa kweli kujaribu kitu sana unfamiliar na wasiwasi sana

606
00:36:43,660 --> 00:36:45,540
kwa ajili yangu kwa wakati.

607
00:36:45,540 --> 00:36:49,440
>> Hivyo katika suala sasa ya nini jukumu Anglès mbalimbali ambayo unaweza

608
00:36:49,440 --> 00:36:51,530
mbinu shaka hii kutumika -

609
00:36:51,530 --> 00:36:53,080
hivyo mihadhara. Ni juu yako.

610
00:36:53,080 --> 00:36:56,550
Kama wewe kushiriki pamoja nasi katika mtu katika ukumbi huu, kwa kweli, tunajua

611
00:36:56,550 --> 00:37:00,920
kitakwimu kwamba takribani 40% ya wewe aina ya kuja na kwenda juu ya

612
00:37:00,920 --> 00:37:05,140
kozi ya muhula, na 10% ya wewe sisi kamwe kuona tena baada ya leo.

613
00:37:05,140 --> 00:37:07,540
Na kwamba kikamilifu faini, na kuwa waaminifu.

614
00:37:07,540 --> 00:37:10,470
Moja ya tabia ya kufafanua CS50 ni kwamba kuna hawa

615
00:37:10,470 --> 00:37:14,220
rasilimali wasiohesabika, ambayo baadhi tutaweza kumkasirisha kupitia katika muda tu,

616
00:37:14,220 --> 00:37:17,890
ikiwa ni pamoja na mihadhara na sehemu, na mambo kuitwa walkthroughs, na ofisi

617
00:37:17,890 --> 00:37:20,850
masaa, na kama, na ni zaidi kuliko rasilimali mwanafunzi typical

618
00:37:20,850 --> 00:37:24,400
wanapaswa kuwa na au inaweza kuchukua faida ya kimwili, lakini hiyo ni kwa sababu

619
00:37:24,400 --> 00:37:27,510
ya disparate mitindo ya kujifunza kwamba yoyote mwanafunzi mwili inajidhihirisha.

620
00:37:27,510 --> 00:37:31,590
Na hivyo katika hotuba, jukumu la msingi kama mimi kuona ni si kwa maneno kushinikiza

621
00:37:31,590 --> 00:37:35,360
nje nyenzo uungwana tata na lazima kutoa yote ya

622
00:37:35,360 --> 00:37:39,040
intricacies ya misingi kwamba tutaweza kutafiti hii muhula, lakini

623
00:37:39,040 --> 00:37:42,430
badala yake, kwa kufanya mambo kama tumekuwa kufanya hivi sasa tayari, mifano

624
00:37:42,430 --> 00:37:46,480
kuwashirikisha binadamu juu ya hatua ya kujaribu kuchora picha ya akili, na pia

625
00:37:46,480 --> 00:37:49,430
kujenga, kuthubutu nasema, baadhi ya nyakati hizi kukumbukwa, ili hata kama wewe

626
00:37:49,430 --> 00:37:53,280
mapambano na mada fulani, una kumbukumbu hizi, kama oh, hata ingawa

627
00:37:53,280 --> 00:37:56,740
kwamba alikuwa uungwana abstractly, math, mimi yalichuliwa kwa kufanya moja, kama,

628
00:37:56,740 --> 00:38:00,260
ni kweli, mwisho wa siku, si tofauti kwamba wote kwa kitu mimi

629
00:38:00,260 --> 00:38:01,060
tayari kujua.

630
00:38:01,060 --> 00:38:04,560
Na hivyo jukumu kwamba mihadhara kuwatumikia aidha katika mtu hapa katika Sanders

631
00:38:04,560 --> 00:38:09,040
au online kwenye video ni kweli kwa kuweka hatua kiakili kwa wewe kila wiki

632
00:38:09,040 --> 00:38:12,370
kwa dhana mbalimbali na matatizo ambayo tutaweza kuwa mbizi katika.

633
00:38:12,370 --> 00:38:16,800
>> Katika suala la dhana ya kiwango cha juu, zaidi ya maneno haya yanaweza kutiririka juu

634
00:38:16,800 --> 00:38:17,670
kichwa yako kwa sasa.

635
00:38:17,670 --> 00:38:18,680
Na kwamba ni faini.

636
00:38:18,680 --> 00:38:21,210
Wale ambao wataingia katika kozi vizuri zaidi kujua ya

637
00:38:21,210 --> 00:38:24,870
baadhi ya mada hii, lakini kwa kawaida kwa kuwa 10% ya darasa kwa ajili ya ambayo

638
00:38:24,870 --> 00:38:28,600
wana mengi zaidi background, kuchukua AP sayansi ya kompyuta, programu tangu

639
00:38:28,600 --> 00:38:31,850
walikuwa 12, kutambua kwamba kutakuwa na fursa katika sehemu na

640
00:38:31,850 --> 00:38:36,030
tatizo seti kwenda kina wote zaidi katika mada mbalimbali, kujaza

641
00:38:36,030 --> 00:38:39,590
chochote mapengo unaweza kuwa kutoka shule yako high au kabla background.

642
00:38:39,590 --> 00:38:43,440
Katika suala la lugha, kutambua kwamba lugha gani sisi kutumia katika CS50 ni

643
00:38:43,440 --> 00:38:45,360
kiasi kikubwa lisilo mwisho wa siku.

644
00:38:45,360 --> 00:38:49,500
Sisi kutokea kwa kutumia kimsingi lugha inayoitwa C. Kwenye mwisho wa

645
00:38:49,500 --> 00:38:53,260
muhula, sisi kuanzisha lugha mtandao-centric, kama PHP na javascript.

646
00:38:53,260 --> 00:38:56,800
Lakini sisi na wengine inaweza kufundisha kozi kama hii katika zaidi yoyote ya kisasa

647
00:38:56,800 --> 00:38:57,740
ngazi ya juu ya lugha -

648
00:38:57,740 --> 00:39:01,710
Chatu, na Ruby, na wengine ni maarufu kabisa siku hizi, kwa sababu kutambua,

649
00:39:01,710 --> 00:39:04,350
mwisho wa siku, wewe si kujifunza katika hii C. Wewe si

650
00:39:04,350 --> 00:39:06,310
kujifunza PHP au JavaScript.

651
00:39:06,310 --> 00:39:10,190
Wewe ni kujifunza jinsi ya kutatua matatizo, kama msingi mtandao, kompyuta makao, au

652
00:39:10,190 --> 00:39:14,810
data-oriented yenyewe, kwa kutumia haya tu kama zana.

653
00:39:14,810 --> 00:39:17,910
>> Sasa katika upande wa vifaa, itabidi kutumia kitu hatimaye kuitwa

654
00:39:17,910 --> 00:39:18,810
CS50 appliance.

655
00:39:18,810 --> 00:39:22,150
Haijalishi kama una Mac, PC, kompyuta Linux, au kama,

656
00:39:22,150 --> 00:39:25,740
itabidi uhuru inapatikana programu kuanzia wiki ijayo na ambayo kwa kutumia

657
00:39:25,740 --> 00:39:28,890
Appliance CS50, mazingira virtual utakayoitumia juu yako

658
00:39:28,890 --> 00:39:32,720
kompyuta mwenyewe, ili wewe na wote wa wanafunzi wako kuwa Linux sare

659
00:39:32,720 --> 00:39:34,220
desktop katika kesi hii.

660
00:39:34,220 --> 00:39:37,010
Ni seti tatizo, ingawa, ambayo itabidi kweli kupata mikono yako

661
00:39:37,010 --> 00:39:37,910
chafu katika shaka.

662
00:39:37,910 --> 00:39:40,820
Na mwisho wa siku, ni seti tatizo, nadhani, kwamba kweli

663
00:39:40,820 --> 00:39:43,510
define uzoefu wa mwanafunzi katika kozi hii.

664
00:39:43,510 --> 00:39:46,660
Kutambua kwamba wengi wa seti tatizo itakuwa iliyotolewa katika matoleo mawili -

665
00:39:46,660 --> 00:39:50,140
toleo la kawaida kwamba sisi kutarajia na kuhimiza 90% ya

666
00:39:50,140 --> 00:39:51,690
darasa kwa kupiga mbizi katika.

667
00:39:51,690 --> 00:39:55,255
Lakini sisi pia iliyotolewa seti baadhi tatizo katika matoleo hacker kinachojulikana, na wewe

668
00:39:55,255 --> 00:39:58,110
najua ni toleo hacker, kwa sababu juu ya kila ukurasa na watermark, ni

669
00:39:58,110 --> 00:39:59,970
anasema hacker toleo juu yake.

670
00:39:59,970 --> 00:40:03,390
Na kwamba ni kwa ajili ya hii kidemografia mlio na AP kompyuta sayansi na 10

671
00:40:03,390 --> 00:40:06,500
miaka ya programu chini ya ukanda yako, na ni kuangalia kujaza mapengo hayo,

672
00:40:06,500 --> 00:40:10,170
na kuwa na rasmi zaidi, badala ya kujitegemea inamruhusu mafunzo labda, kutambua

673
00:40:10,170 --> 00:40:13,420
kwamba kuna idadi ya watu sana kikubwa katika darasa kwamba ana

674
00:40:13,420 --> 00:40:15,230
just kwamba lengo moja.

675
00:40:15,230 --> 00:40:16,460
Itabidi tano marehemu siku.

676
00:40:16,460 --> 00:40:19,380
Tatizo ni seti ujumla kutokana Alhamisi, lakini unaweza kupanua tano ya

677
00:40:19,380 --> 00:40:22,900
wale uliopangwa kutumia mambo haya kuitwa marehemu siku, na tutaweza pia tone

678
00:40:22,900 --> 00:40:25,520
alama yako ya chini mwisho wa muhula, kwa

679
00:40:25,520 --> 00:40:27,540
maelezo katika mtaala.

680
00:40:27,540 --> 00:40:31,630
>> Lakini mwingine tabia ya kufafanua CS50 zaidi ya miaka imekuwa ofisi

681
00:40:31,630 --> 00:40:36,060
masaa, nafasi ulizoziona katika kuibua photos kidogo iliyopita ambayo

682
00:40:36,060 --> 00:40:39,090
sisi kukusanya awali katika kumbi dining nyumba, kabla ya kuwa katika

683
00:40:39,090 --> 00:40:42,120
Lelo wa kituo cha sayansi, na mwaka huu katika Annenberg Hall, nne

684
00:40:42,120 --> 00:40:45,670
usiku wiki kutoka mchana 8:00-11:00, ambapo itabidi hii sana

685
00:40:45,670 --> 00:40:49,810
pamoja na uzoefu wa kazi, wanajitahidi kwa njia ya matatizo fulani,

686
00:40:49,810 --> 00:40:52,520
lakini kwa msaada mkubwa katika mfumo wa mahali.

687
00:40:52,520 --> 00:40:55,780
Kwa hakika, njia hii kazi ni wewe utakuwa kuwasili katika Annenberg kama una

688
00:40:55,780 --> 00:40:56,950
baadhi swali wakati wa wiki.

689
00:40:56,950 --> 00:41:00,190
Wewe utakuwa kuleta Laptop yako, itabidi kukaa chini, kunyakua baadhi ya chakula, na wewe utakuwa kuingia

690
00:41:00,190 --> 00:41:04,100
katika CS50 Diskutera, shirika mtandao msingi kwamba wafanyakazi mafundisho ina

691
00:41:04,100 --> 00:41:07,860
maendeleo ambayo itawawezesha post maswali na kuona followups katika

692
00:41:07,860 --> 00:41:12,590
typical majadiliano jukwaa hisia, kwa kutumia maandiko na kama, na auto-kamili

693
00:41:12,590 --> 00:41:13,790
kutafuta data.

694
00:41:13,790 --> 00:41:17,950
Lakini utasikia pia kuwa na uwezo wa wakati wa saa ya masaa ya ofisi, na yako

695
00:41:17,950 --> 00:41:20,490
maswali ilienea kwa viumbe halisi ya binadamu.

696
00:41:20,490 --> 00:41:24,000
Hakika, lengo ni hatimaye ili moja, tunaanza kujenga juu ya

697
00:41:24,000 --> 00:41:27,740
kozi ya muhula corpus wa habari hopefully muhimu kweli kweli,

698
00:41:27,740 --> 00:41:31,770
kawaida majibu ya maswali ya kawaida, hivyo kuwa wewe mwenyewe anaweza kutatua matatizo

699
00:41:31,770 --> 00:41:35,980
na kupata unstuck haraka iwezekanavyo, wakati akiwa mafundisho

700
00:41:35,980 --> 00:41:40,320
wafanyakazi - kwa kawaida 20% hadi 30% ya wenzake mafundisho na bila shaka wasaidizi

701
00:41:40,320 --> 00:41:41,780
juu ya wafanyakazi kwa mara moja.

702
00:41:41,780 --> 00:41:45,150
>> Tutakuwa na kile kinachoitwa Greeter CS50 katika Annenberg, na wakati sisi

703
00:41:45,150 --> 00:41:46,610
kuamua kwamba, unajua nini?

704
00:41:46,610 --> 00:41:50,900
Swali hili, kwa kweli sisi kujibu kwa ufanisi online.

705
00:41:50,900 --> 00:41:51,930
Tunataka kuona kompyuta yako.

706
00:41:51,930 --> 00:41:53,470
Tunataka kuzungumza na wewe mmoja mmoja.

707
00:41:53,470 --> 00:41:56,060
Wewe ni kweli wanajitahidi, na wewe kwa hiyo wanataka kuzungumza moja kwa moja

708
00:41:56,060 --> 00:41:59,160
sambamba mtu, wewe utakuwa dispatched Greeter CS50,

709
00:41:59,160 --> 00:42:02,700
mafundisho wenzake kuikopesha, literally, iPod ambayo ina majina ya wanafunzi juu ya moja

710
00:42:02,700 --> 00:42:04,880
upande, akifundisha majina ya wafanyakazi juu ya nyingine.

711
00:42:04,880 --> 00:42:07,900
Sisi kukusanya jina lako, na kufuatiwa na jina la wafanyakazi mafundisho, na yako

712
00:42:07,900 --> 00:42:12,020
kompyuta screen kuanza blinking, akisema tafadhali kwenda kuona Alice au tafadhali

713
00:42:12,020 --> 00:42:14,110
kwenda kuona Bob mezani wafanyakazi.

714
00:42:14,110 --> 00:42:17,240
Na hivyo kwa njia hii, tutaweza kuwa na uwezo wa kupeleka mambo kama ufanisi kama

715
00:42:17,240 --> 00:42:22,030
iwezekanavyo, kama vile kuongoza wewe kuelekea ufumbuzi wote kwa urahisi zaidi.

716
00:42:22,030 --> 00:42:25,900
Katika sehemu, haya itakuwa fursa kwa ionekane zaidi mikono-

717
00:42:25,900 --> 00:42:30,080
juu ya fursa na mmoja wa wenzake mafundisho na 12 hadi 16 au zaidi ya

718
00:42:30,080 --> 00:42:34,020
wanafunzi wako, ambapo kila wiki, tutaweza kuwa na matatizo katika kuweka tatizo

719
00:42:34,020 --> 00:42:36,750
kwamba kuuliza maswali kadhaa dhana, na idadi ya bite ukubwa

720
00:42:36,750 --> 00:42:39,180
programu maswali kwamba unaweza kufikiri juu yako mwenyewe, na unaweza

721
00:42:39,180 --> 00:42:42,140
kazi juu yako mwenyewe, lakini katika mazingira ya sehemu, tutaweza kufanya kazi kwa njia ya

722
00:42:42,140 --> 00:42:45,230
pamoja na baadhi ya matatizo hayo na kwenda wapi

723
00:42:45,230 --> 00:42:46,700
mazungumzo inachukua sisi.

724
00:42:46,700 --> 00:42:51,340
>> Aidha, katika sehemu ya mapenzi una fursa ya kupitia maoni ya

725
00:42:51,340 --> 00:42:54,470
homework kwamba kiunda, wanafunzi wako, wakati mwingine anonymized,

726
00:42:54,470 --> 00:42:56,780
daima na opt-katika, kama ungependa kushiriki

727
00:42:56,780 --> 00:42:57,930
kazi kwamba ve in.

728
00:42:57,930 --> 00:43:00,890
Hivyo itabidi kweli kuwa mazungumzo mbili-directional, na nafasi ya

729
00:43:00,890 --> 00:43:05,050
kupitia kazi yako mwenyewe kwa maana ya zaidi ya nguvu, kuliko tu

730
00:43:05,050 --> 00:43:08,620
kuangalia PDF au printout na kufikiri juu yake kwa sekunde chache

731
00:43:08,620 --> 00:43:10,760
na si lazima absorbing maoni kwamba

732
00:43:10,760 --> 00:43:12,270
walimu wametoa.

733
00:43:12,270 --> 00:43:14,670
Na wewe utakuwa kutumia zana hapa aitwaye CS50 Spaces.

734
00:43:14,670 --> 00:43:18,165
Kwa wale unfamiliar, hii ni lugha inayojulikana kama C juu kushoto, na

735
00:43:18,165 --> 00:43:21,360
utapata kujua hii ya muda, lakini hii ni shirika la mtandao msingi kwamba tutaweza

736
00:43:21,360 --> 00:43:25,350
kutumia katika sehemu ambayo itawawezesha na classmates wako 15 au ili kuingia na

737
00:43:25,350 --> 00:43:27,120
ufundishaji wako wenzake mbele ya chumba.

738
00:43:27,120 --> 00:43:28,890
Wewe utakuwa na uwezo wa kuandika code katika dirisha hili.

739
00:43:28,890 --> 00:43:31,800
Wewe utakuwa na uwezo wa kuzungumza kielektroniki kama wewe si kweli katika sehemu katika

740
00:43:31,800 --> 00:43:35,300
kwamba sasa hasa, na mafundisho yako wenzake, linapokuja wakati ili

741
00:43:35,300 --> 00:43:41,295
kujadili Alice au ufumbuzi Bob katika darasa, kufundisha wenzao wanaweza bonyeza

742
00:43:41,295 --> 00:43:45,210
button, na voilà, mradi kwenye screen kila mwanafunzi imekuwa

743
00:43:45,210 --> 00:43:47,120
kazi katika hatua hiyo hasa kwa wakati.

744
00:43:47,120 --> 00:43:50,400
Hivyo kwa wale wa wewe kuwa na marafiki ambao wamechukua CS50 katika siku za nyuma, kutambua

745
00:43:50,400 --> 00:43:53,790
kuwa vifungu wamekuwa kikubwa rebooted mwaka huu ili kuwa zaidi ya yote

746
00:43:53,790 --> 00:43:57,700
kazi, zaidi ya nguvu zote, na kweli, mazungumzo ya pande mbili kati ya

747
00:43:57,700 --> 00:44:00,300
kufundisha wafanyakazi na wanafunzi.

748
00:44:00,300 --> 00:44:01,160
>> Na walkthroughs.

749
00:44:01,160 --> 00:44:04,520
Hivyo kwa seti hizi tatizo, sisi pia kutoa si tu vipimo

750
00:44:04,520 --> 00:44:08,110
yenyewe, ambayo ni jumla ya PDF uungwana ya kina, lakini pia mambo inayojulikana

751
00:44:08,110 --> 00:44:12,070
kama walkthroughs, ambapo mwanachama mmoja wa wafanyakazi wa mafundisho itasababisha kila wiki

752
00:44:12,070 --> 00:44:15,460
kikao kwamba literally matembezi yenu kupitia kuweka tatizo, kutoa

753
00:44:15,460 --> 00:44:18,700
vidokezo na ushauri, na pointi ya kuanzia, na ni maana ya kuuliza sana

754
00:44:18,700 --> 00:44:21,370
mara nyingi aliuliza swali: wapi mimi kuanza?

755
00:44:21,370 --> 00:44:25,550
Naam, kuanza ama kwa mbizi katika spec juu yake mwenyewe, au kwa kuhudhuria

756
00:44:25,550 --> 00:44:27,230
au kuangalia walkthroughs haya.

757
00:44:27,230 --> 00:44:29,550
walkthrough kwanza, kwa kweli, itakuwa hiyo Ijumaa.

758
00:44:29,550 --> 00:44:32,120
Wao utakuwa juu ya Ijumaa, si sana kwa sababu tunadhani utakuwa maarufu

759
00:44:32,120 --> 00:44:34,940
muda, lakini kwa sababu tunaweza basi filamu yao mapema sana katika wiki na kupata

760
00:44:34,940 --> 00:44:38,410
nao online na mwishoni mwa wiki ili una kama siku nyingi kama inawezekana

761
00:44:38,410 --> 00:44:40,530
kweli kushiriki katika maudhui kuwa vilevile.

762
00:44:40,530 --> 00:44:43,050
Lakini zaidi juu ya kwamba katika hotuba hii ya Ijumaa.

763
00:44:43,050 --> 00:44:46,930
>> Sasa katika suala la muundo msaada, statistic ya muhimu zaidi ni

764
00:44:46,930 --> 00:44:50,600
labda 108 mafundisho wenzake na wasaidizi shaka kwamba hii bila shaka

765
00:44:50,600 --> 00:44:51,870
sasa ina.

766
00:44:51,870 --> 00:44:54,490
Kama baadhi ya wewe ambao hawana madarasa yanayokinzana ungependa kujiunga

767
00:44:54,490 --> 00:44:58,900
me up hapa juu ya hatua, ni haya guys ambao hatimaye kweli define yako

768
00:44:58,900 --> 00:45:00,150
uzoefu katika shaka.

769
00:45:08,890 --> 00:45:11,870
Mimi nilikuwa na mengi ya wenzake kufundisha mafundisho yangu madarasa katika siku, na mimi

770
00:45:11,870 --> 00:45:15,650
kumbuka sana wale wachache, kusema ukweli, lakini hadi sasa, mimi bado kukumbuka miongoni mwa

771
00:45:15,650 --> 00:45:19,990
wale wachache yangu CS50 TF, ambao kwa kweli imenisaidia kujibu maswali, ambao kwa kweli

772
00:45:19,990 --> 00:45:22,830
imenisaidia nilipokuwa wanajitahidi, na kwa kweli alikuwa mshirika katika hii

773
00:45:22,830 --> 00:45:25,770
uzoefu wa kujifunza dunia mpya sana.

774
00:45:25,770 --> 00:45:29,100
Katika kidogo, wote wa guys hawa wataungana wewe nje kwa keki, ambayo

775
00:45:29,100 --> 00:45:32,560
ni mapokeo ya CS50, katika transept ya Memorial Hall, lakini napenda

776
00:45:32,560 --> 00:45:36,980
kwanza kuanzisha wewe Nate Hardison tena, Rob Bowden, na Tommy

777
00:45:36,980 --> 00:45:39,370
McWilliams, kozi ya mwaka huu anaongoza.

778
00:45:39,370 --> 00:45:41,385
Kama wewe guys ingekuwa kujiunga na mimi hapa katikati.

779
00:45:47,380 --> 00:45:50,045
Wao wote tayari matamshi baadhi inspirational.

780
00:45:53,212 --> 00:45:55,775
>> Tommy McWilliams: sikuwa kuandaa kitu chochote inspirational.

781
00:45:55,775 --> 00:45:57,170
Lakini jina langu ni Tommy.

782
00:45:57,170 --> 00:45:58,370
Mimi nina mwandamizi katika Mather.

783
00:45:58,370 --> 00:46:01,620
Mimi kusoma sayansi ya kompyuta, na kwa kweli msisimko kuwa katika timu ya vichwa

784
00:46:01,620 --> 00:46:03,720
kwenda kwa safari CS50 na wewe.

785
00:46:03,720 --> 00:46:06,750
Nini mimi kweli upendo kuhusu CS50 ni jinsi ni kweli inafundisha kufikiri kuhusu

786
00:46:06,750 --> 00:46:08,180
matatizo katika njia mpya.

787
00:46:08,180 --> 00:46:11,170
Hii ni kweli ujuzi kwamba itakuja kuwa mchango mkubwa sana, bila kujali shamba

788
00:46:11,170 --> 00:46:12,090
kwenda katika.

789
00:46:12,090 --> 00:46:14,800
Na si tu kwamba, lakini sisi kutoa zaidi bure pipi kuliko yoyote

790
00:46:14,800 --> 00:46:16,050
nyingine bila shaka juu ya chuo.

791
00:46:22,730 --> 00:46:24,350
Hivyo mimi nina kweli tu kuangalia mbele kuona nini

792
00:46:24,350 --> 00:46:25,645
kila mtu hujenga hii muhula.

793
00:46:25,645 --> 00:46:28,860
Na kama mtu ana maswali yoyote sasa au katika muhula, dhahiri

794
00:46:28,860 --> 00:46:32,976
jisikie huru kufikia nje kwangu, na ningependa kuwa na furaha na kusaidia.

795
00:46:32,976 --> 00:46:33,920
>> Rob Bowden: Hi.

796
00:46:33,920 --> 00:46:34,670
Mimi nina Rob Bowden.

797
00:46:34,670 --> 00:46:35,920
Mimi nina mwandamizi katika Kirkland.

798
00:46:40,030 --> 00:46:41,890
Yeah, hiyo ni haki.

799
00:46:41,890 --> 00:46:44,070
Sisi sote ni kweli msisimko kwa muhula huu ujao.

800
00:46:44,070 --> 00:46:45,325
Ni matumaini yetu wewe ni msisimko wote.

801
00:46:49,850 --> 00:46:51,580
Mimi si kutarajia kwamba.

802
00:46:51,580 --> 00:46:52,530
Yeah.

803
00:46:52,530 --> 00:46:56,030
Hivyo sisi kuweka sana juhudi katika kufanya muhula kweli hii kubwa, na kama

804
00:46:56,030 --> 00:46:58,830
muda mrefu kama wewe ni tayari kuweka katika juhudi, kuna mengi unaweza kupata

805
00:46:58,830 --> 00:47:00,080
nje ya kozi hii.

806
00:47:06,810 --> 00:47:10,470
Unaweza kupata mengi ya furaha nje ya kozi hii.

807
00:47:10,470 --> 00:47:13,510
Sisi bila kuwa na wafanyakazi wa 108 kama unaweza kupata mengi ya furaha nje ya hayo,

808
00:47:13,510 --> 00:47:17,450
hivyo tu jaribu kushiriki, na utakuwa ni majuto.

809
00:47:24,815 --> 00:47:26,020
>> Nate HARDISON: Hi, guys.

810
00:47:26,020 --> 00:47:26,930
Mimi nina Nate.

811
00:47:26,930 --> 00:47:29,700
Mimi nina preceptor kwa ajili ya kozi.

812
00:47:29,700 --> 00:47:31,200
Mimi kwa kweli msisimko kuwa hapa pia.

813
00:47:31,200 --> 00:47:33,100
Huu ni mwaka wangu wa kwanza hapa.

814
00:47:33,100 --> 00:47:36,520
Natumaini wote kuchukua kozi hii, na kufurahia kama vile mimi wameweza

815
00:47:36,520 --> 00:47:37,960
walifurahia hivyo mbali.

816
00:47:37,960 --> 00:47:41,520
Na kama wewe milele unataka kujifunza jinsi ya kuja tisa au kumi katika binary, kuja

817
00:47:41,520 --> 00:47:43,351
kuzungumza na mimi.

818
00:47:43,351 --> 00:47:46,480
>> SPIKA 1: Hivyo katika hatari ya kuacha guys haya hapa juu ya hatua kidogo

819
00:47:46,480 --> 00:47:50,330
awkwardly, hebu whirl kupitia chache tu ya mambo ambayo wakisubiri kabla sisi

820
00:47:50,330 --> 00:47:51,500
kuahirishwa kwa keki.

821
00:47:51,500 --> 00:47:52,980
Nini ni kwamba uongo mbele?

822
00:47:52,980 --> 00:47:56,410
Naam, kama sisi kuchukua kuangalia haraka nyuma katika mwaka wa mwisho, katika tatizo kuweka sifuri, yako

823
00:47:56,410 --> 00:47:59,960
watangulizi njiwa katika lugha ya programu inayoitwa Scratch, graphical

824
00:47:59,960 --> 00:48:03,160
programu lugha utasikia kutumia katika siku ya kwanza ya shaka, kuanzia

825
00:48:03,160 --> 00:48:07,080
hii Ijumaa, kwa kujifunza mawazo ya baadhi unfamiliar kwa baadhi yenu, lakini kutambua

826
00:48:07,080 --> 00:48:10,330
kutakuwa na nyanja ya juu ya hili kwa wale wa wewe kwa kabla

827
00:48:10,330 --> 00:48:11,070
background.

828
00:48:11,070 --> 00:48:14,082
>> Katika tatizo mwaka jana kuweka mbili, wanafunzi njiwa katika ulimwengu wa

829
00:48:14,082 --> 00:48:17,740
cryptography, sanaa ya enciphering au scrambling habari,

830
00:48:17,740 --> 00:48:21,310
kutekeleza mipango ya kwamba data encrypted, na katika toleo la mwisho hacker

831
00:48:21,310 --> 00:48:26,710
mwaka gani wanafunzi kuendelea na ufa au Decode nywila katika mfano

832
00:48:26,710 --> 00:48:31,190
kompyuta xc. password faili na kuja na algorithms na heuristics kwa

833
00:48:31,190 --> 00:48:34,980
nguvu brute kuhesabia nje nini password ya mtu kwenye kompyuta

834
00:48:34,980 --> 00:48:35,770
mfumo ilikuwa.

835
00:48:35,770 --> 00:48:39,820
Mwaka jana au mbili, katika tatizo kuweka nne wanafunzi walifanya

836
00:48:39,820 --> 00:48:41,420
kutekeleza mchezo wa Sudoku.

837
00:48:41,420 --> 00:48:45,180
Na toleo hacker kwamba mwaka gani wanafunzi si tu kutekeleza jinsi ya

838
00:48:45,180 --> 00:48:49,360
kucheza mchezo, lakini kwa kweli solver, ambapo kompyuta inaweza kutoa,

839
00:48:49,360 --> 00:48:52,260
binadamu, na mwanga, na kwa haraka zaidi kuliko wewe kutatua

840
00:48:52,260 --> 00:48:53,550
kwamba tatizo fulani.

841
00:48:53,550 --> 00:48:57,420
>> Katika tatizo kuweka tano, sisi alifanya forensics, sanaa hii ya kurejesha taarifa

842
00:48:57,420 --> 00:49:00,160
kwamba ilikuwa ajali au sana kwa makusudi

843
00:49:00,160 --> 00:49:01,450
ilifutwa kutoka kwa kompyuta.

844
00:49:01,450 --> 00:49:04,530
Mwaka jana, walimu na mimi strolled kote kampasi kuchukua

845
00:49:04,530 --> 00:49:07,780
picha za watu, mahali, na vitu na kisha ajali

846
00:49:07,780 --> 00:49:10,900
formatted kadi ya vyombo vya habari juu ya kamera yetu kwamba alikuwa na wale picha zote.

847
00:49:10,900 --> 00:49:15,920
Lakini hakuna tatizo, sisi alifanya sanamu ya forensics kadi hii vyombo vya habari, mitupu nje

848
00:49:15,920 --> 00:49:19,410
kwa wanafunzi wote katika darasa, na changamoto waandike mipango

849
00:49:19,410 --> 00:49:22,240
zinalipwa wote wa JPEGs kutoka kadi hiyo.

850
00:49:22,240 --> 00:49:24,720
Na hii ni kweli moja ya seti favorite yetu tatizo, na mimi kuchimbwa up

851
00:49:24,720 --> 00:49:27,750
zamani ya barua pepe kutoka kwa mmoja wa watangulizi yako ambayo ilikuwa kubwa fun

852
00:49:27,750 --> 00:49:29,940
kusoma wakati mwingine iliyopita.

853
00:49:29,940 --> 00:49:31,270
>> Hii ni kutoka Mt.

854
00:49:31,270 --> 00:49:34,970
Ndugu Daudi, jana ndugu yangu ajali formatted kamera yake SD

855
00:49:34,970 --> 00:49:37,770
kadi na waliopotea mwaka thamani ya photos kukumbukwa.

856
00:49:37,770 --> 00:49:40,830
Yeye kwa bahati mbaya si bora katika inaunga mkono up data yake.

857
00:49:40,830 --> 00:49:43,780
Lakini hali hii inanikumbusha p-set tano, hivyo mimi nilifikiri ingekuwa kujaribu

858
00:49:43,780 --> 00:49:47,620
kukimbia kadi yake SD kupitia mpango kupona kwamba mimi aliandika njia yote nyuma

859
00:49:47,620 --> 00:49:48,180
katika Oktoba.

860
00:49:48,180 --> 00:49:51,660
Hivyo baada ya masaa manne ya kuhesabia nje ya jinsi ya kujenga picha ghafi kutoka

861
00:49:51,660 --> 00:49:53,350
formatted SD kadi -

862
00:49:53,350 --> 00:49:56,050
Google kuthibitisha kuwa pretty kusaidia katika suala hili, hata mimi hazijaingizwa

863
00:49:56,050 --> 00:50:00,140
kilichotokea kwa kuja hela maelekezo yako kwenye mtandao -

864
00:50:00,140 --> 00:50:03,080
baada ya kuchezea karibu na baadhi ya hoja mstari amri, mimi imeweza

865
00:50:03,080 --> 00:50:06,020
kwa kujenga picha ya kuchunguza mauaji, na baada ya kufunga na Configuring

866
00:50:06,020 --> 00:50:10,600
CS50 Appliance, mimi imeweza kuendesha image kuchunguza mauaji kupitia mpango wangu na

867
00:50:10,600 --> 00:50:16,065
kuokoa wote 1027 wa picha dada yangu, anaandika Mt.

868
00:50:25,210 --> 00:50:28,600
>> Katika kuweka tatizo mwaka jana sita, sisi aliwapa wanafunzi kamusi ya

869
00:50:28,600 --> 00:50:33,350
150,000 maneno ya Kiingereza na changamoto waandike kusahihisha Spell kwamba

870
00:50:33,350 --> 00:50:36,870
maswali akajibu wa fomu, ni neno hili yameendelezwa vizuri au kwa usahihi

871
00:50:36,870 --> 00:50:38,150
haraka iwezekanavyo.

872
00:50:38,150 --> 00:50:41,900
Na juu ya opt-katika misingi walikuwa wanafunzi kuruhusiwa kisha changamoto wanafunzi

873
00:50:41,900 --> 00:50:45,220
na posting matokeo yao, kiasi cha RAM kwamba wanatumia, idadi ya

874
00:50:45,220 --> 00:50:49,190
CPU mizunguko au sekunde kwamba wao kutumika, hivyo kwamba wanafunzi walikuwa kisha ranked juu ya

875
00:50:49,190 --> 00:50:53,010
tovuti ya shaka - tena, kipengele rena hiari yake, lakini furaha kubwa

876
00:50:53,010 --> 00:50:56,970
kwa kuwa mara nyingi sana bila mwanafunzi kupata nafasi namba 10 au kadhalika kubwa

877
00:50:56,970 --> 00:51:00,370
bodi, kwenye tovuti, kwenda mbali na chakula cha jioni na kisha kuja nyuma, na kutambua

878
00:51:00,370 --> 00:51:04,340
roommate wake alikuwa tu kuwili mbele yake au yake juu ya bodi kubwa,

879
00:51:04,340 --> 00:51:07,620
hivyo kumtia saa nyingine mbili au tatu tu kwa moja

880
00:51:07,620 --> 00:51:09,300
yake au roommate wake up.

881
00:51:09,300 --> 00:51:11,730
>> Hivyo tunatazamia kwa kitu sawa mwaka huu pia.

882
00:51:11,730 --> 00:51:15,400
Katika tatizo kuweka 7 gani sisi Bad katika mwelekeo wa programu za mtandao, kweli

883
00:51:15,400 --> 00:51:19,320
kutatua matatizo katika mazingira ya milele-yanazidi kuwa ya kawaida

884
00:51:19,320 --> 00:51:20,300
ya kivinjari.

885
00:51:20,300 --> 00:51:23,670
Basi jueni decreasingly gani sisi download programu kwenye Macs na PC, lakini

886
00:51:23,670 --> 00:51:25,790
inazidi, je, sisi kufanya yote ndani ya mtandao.

887
00:51:25,790 --> 00:51:30,140
>> Na kwa kweli, mwaka jana, baadhi ya 88% ya miradi ya wanafunzi wa mwisho katika kozi

888
00:51:30,140 --> 00:51:31,790
walikuwa mtandao msingi.

889
00:51:31,790 --> 00:51:34,670
Na wale, pia, ni ujuzi kwamba wewe hupata kutoka darasa hili kwa

890
00:51:34,670 --> 00:51:38,410
mwisho shaka, kwa sababu gani watapata mwishoni shaka ni Fair CS50, hii

891
00:51:38,410 --> 00:51:42,100
maonyesho yale ya msingi juu ya wazo la haki ya sayansi, lakini katika toleo la

892
00:51:42,100 --> 00:51:45,370
haki kufanya wanafunzi wote katika darasa kuleta Laptops zao, na wao

893
00:51:45,370 --> 00:51:49,720
marafiki, na jamaa, na wengine Northwest Sayansi, jengo kubwa juu ya

894
00:51:49,720 --> 00:51:53,420
chuo, kuanzisha Laptop zao, kupata chakula, kupata baadhi ya popcorn na kinywaji, na

895
00:51:53,420 --> 00:51:57,180
kisha maonyesho miradi yao ya mwisho kwa mahudhurio katika wale wote, ambaye mwaka jana

896
00:51:57,180 --> 00:52:01,510
kuhesabiwa waliohudhuria baadhi 2500 kutoka katika chuo hicho, na misemo kama

897
00:52:01,510 --> 00:52:05,510
huu, na kama hii walikuwa si kawaida katika haki.

898
00:52:05,510 --> 00:52:09,660
>> Kuongoza hadi haki ni Hackathon CS50, fursa hop kwenye

899
00:52:09,660 --> 00:52:13,610
Harvard Shuttle, kichwa chini ya mitaani na Microsoft saa 8:00, na si kwenda nyumbani

900
00:52:13,610 --> 00:52:14,810
mpaka 07:00.

901
00:52:14,810 --> 00:52:19,040
Sisi kumtumikia chakula cha jioni ya kwanza katika 20:00, pili chakula cha jioni katika 01:00, na kwa wale ambao bado

902
00:52:19,040 --> 00:52:22,540
amesimama 05:00 gani sisi kutibu kwa pancakes saa IHOP.

903
00:52:22,540 --> 00:52:26,580
Na Hackathon ni nafasi, kama picha hapa, kupiga mbizi katika yako

904
00:52:26,580 --> 00:52:30,470
miradi ya mwisho, kama kazi juu yako mwenyewe au na marafiki katika

905
00:52:30,470 --> 00:52:33,770
shirikishi mazingira, ambapo nzima mafundisho wafanyakazi ni kufanya kazi vizuri

906
00:52:33,770 --> 00:52:37,560
katika usiku na ugavi wa kutosha wa chakula Hong Kong Kichina.

907
00:52:37,560 --> 00:52:43,070
Katika 05:00 mapenzi vile images kama hizi kuwa kawaida kabisa mwaka huu pia.

908
00:52:43,070 --> 00:52:48,170
>> Hivyo kama sisi kuahirishwa kwa dakika kwa keki, kukumbuka kwamba 76% asilimia ya

909
00:52:48,170 --> 00:52:51,720
watu katika chumba hiki hawana uzoefu kabla, na kama kwa muhtasari,

910
00:52:51,720 --> 00:52:55,300
nini hatimaye mambo katika kozi hii si kiasi ambapo unaishia

911
00:52:55,300 --> 00:52:59,540
jamaa na wanafunzi wako, lakini ambapo, katika wiki 11, kuishia jamaa na

912
00:52:59,540 --> 00:53:01,540
mwenyewe katika wiki 0.

913
00:53:01,540 --> 00:53:03,690
Hii ni CS50.