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>> SPIKA 1: Katika toleo la mwisho la
sigma, mimi kutekelezwa kile ambacho linaweza kujulikana

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ufumbuzi iterative, ambapo Nilikuwa
mbele kitanzi kuhesabu up yote ya

3
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idadi kati ya 1 na m, baada ya hapo
kurudi jumla.

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>> Lakini zinageuka tunaweza kutumia mwingine
mbinu ya kutekeleza hiyo

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kazi, mbinu
inayojulikana kama recursion.

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kazi ya kujirudia, hivyo kusema,
ni moja tu kwamba wito yenyewe.

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Sasa, katika na wenyewe, kwamba
inaweza kuwa tatizo.

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Kama kazi tu wito yenyewe ambayo
wito yenyewe ambayo wito yenyewe,

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mchakato kwamba wanaweza BoT milele mwisho.

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Lakini kwa muda mrefu kama sisi ni pamoja na kinachojulikana
msingi kesi, hali ambayo kuhakikisha

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kwamba katika baadhi ya hali hatuwezi kuwaita
wenyewe, kuwa mchakato wa vinginevyo

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looping usio lazima zitakoma.

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>> Hebu sasa reimplement
sigma kama ifuatavyo.

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Kama n ni chini ya au sawa na 0, mimi nina
tu, na kwa kiasi fulani kiholela,

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kwenda na kurudi 0.

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Mwingine nini mimi kwenda kufanya ni kweli
compute sigma kwa chanya int

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kwamba nimekuwa mitupu.

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>> Sasa, ni nini sigma ya m?

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Naam, sigma ya m ni, bila shaka,
Jumla ya 1 ya juu kupitia m.

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Lakini kama sisi kufikiri juu yake kwa njia nyingine,
ni tu Jumla ya m pamoja na m

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minus 1 pamoja na m bala 2 na kadhalika,
njia yote chini ya 1.

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Hivyo kwa mantiki kwamba, inaonekana kwamba
Mimi naweza tu kurudi m plus.

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>> Na kisha mimi haja m minus
1 pamoja na m bala 2.

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Lakini nina kazi ambayo inaweza kutoa
mimi hasa kwamba jibu, yaani

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sigma ya m minus 1.

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>> Sasa, wito mwenyewe kwa njia hii haina
kuonekana kama wazo bora.

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Kwa sababu kama sigma wito sigma ambayo inatoa wito
sigma ambayo inatoa wito sigma, wewe

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kudhani kwamba mchakato huu
wanaweza milele mwisho.

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Lakini kwamba ni kwa nini tulikuwa kinachojulikana msingi
kesi juu ya kazi hii.

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kama hali ya kwamba hundi kama m ni
chini ya au sawa na 0 Sitakuja

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kuwaita mwenyewe.

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Mimi badala kwenda na kurudi 0, ambayo
kwa upande mwingine ni kwenda kuongezwa kwa

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idadi uliopita kwamba nimekuwa summing
up, na hivyo kuacha hii

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mchakato vinginevyo kubwa.

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>> Hebu sasa kuona kama hii mpya
utekelezaji wa kazi.

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Hebu kuokoa, kukusanya, na
kuendesha mpango huu.

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Kufanya sigma 1 dot kufyeka sigma 1.

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Na hebu kutoa ni pamoja na
idadi sawa mbele.

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2, ambayo inapaswa hopefully nipe 3.

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Hebu kutoa ni pamoja na 3, ambayo
lazima hopefully nipe 6.

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00:01:58,970 --> 00:02:03,480
Na hebu hatimaye kutoa ni pamoja na
50, ambayo kwa hakika anitiaye 1275.

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