Eli licandelo lesibini kuluhlu malunga nokukhetha eyona nto ifanelekileyo yokudibanisa i-container (isichazi-magama) kwi-C ++23. Kwinxalenye yokuqala, sigubungele izikhongozeli ezi-odolweyo , kwaye kweli candelo, siza kuxoxa ngokungacwangciswanga ngokweenkcukacha.

Izikhongozeli ezingacwangciswanga

Ezi zikhongozeli aziboneleli naluphi na ulandelelwano oluchaziweyo lwezitshixo zazo. Ngaphezu koko, i-oda ephambili inokutshintsha ngokuguqulwa ngalunye, ngoko ke inkqubo akufanele ithembele kuyo. Izikhongozeli ezinjalo zihlala ziphunyezwa njengeemephu ze-hash.

Ngokubanzi, xa udibanisa, ususa, okanye ukhangela isitshixo, imephu ye-hash iqala ngokubala ixabiso lehash elidityanisiweyo ukusuka kwelo qhosha usebenzisa umsebenzi we-hash. I-hash (okanye indawo yayo) isetyenziswa njengesalathiso kuluhlu oludibeneyo olwabiwe kwangaphambili. Ungeno ngalunye kolu luhlu lubizwa ngokuba yibhakethi . Amanye amangeno kolo luhlu azakungabi nanto, amanye azakuqulatha into enye, kwaye amanye angenza imephu kwizinto ezingaphezulu kwesinye ngenxa yongquzulwano lwehash. Oku kwenzeka xa izitshixo ezahlukeneyo zinexabiso le-hash elalatha kwisalathiso soluhlu olufanayo. Iimephu zeHash zisebenzisa izicwangciso ezahlukeneyo zokujongana nokungqubana kwe-hash (bona eli nqaku le-Wikipedia ). Inani lezinto ezikwimephu ye-hash ezahlulwe ngobungakanani obupheleleyo boluhlu kuthiwa yimeko yomthwalo . Okukhona uphezulu umba womthwalo, kokukhona ungquzulwano lwe-hash lunokwenzeka ngento nganye esanda kufakwa.

Ngokuchasene nezikhongozeli ezi-odolweyo, iimephu zehash aziyixhasi imibuzo yoluhlu, irenki/khetha imisebenzi, ukuphindaphinda izitshixo ngokulandelelana, kunye nokukhangela isitshixo esincinci/esikhulu kunesitshixo esinikiweyo. Ngembuyekezo, iimephu zehash zifikelela kowona msebenzi ufezekayo: ixesha elintsonkothileyo lophendlo/ukufaka/ukususwa kwemisebenzi ihlawulelwe O(1) . Ndithi "i-amortized" apha, kuba xa inani lezinto lisiba likhulu kakhulu, imephu ye-hash kufuneka iphinde ihlaziye imixholo yayo ukunciphisa umthamo womthwalo (ukukhulisa ngokufanelekileyo uluhlu lwebhakethi). Ubunzima bexesha lokuhlaziya kwakhona ngu O(n) . Nangona kunjalo, kulindeleke ukuba yenzeke ngokunqabileyo, ngoko ke ngokomyinge, umsebenzi ngamnye usengu O(1) . Esinye isizathu sokusebenza okunokuthi kuncitshiswe ngumsebenzi we-hash kunye nokusabalalisa okungahambi kakuhle, okuya kwandisa ukuphindaphinda kokungqubana.

Iimephu zehash eziqhelekileyo

Ukuqala nge-C++11, ilayibrari eqhelekileyo ibonelela ngezi mephu zilandelayo: std::unordered_map ( ikhonkco ), std::unordered_set ( ikhonkco ), std::unordered_multimap ( ikhonkco ), kunye std::unordered_multiset ( ikhonkco ). Iimephu zinxulumanisa isitshixo nexabiso, ngelixa iiseti zigcina isitshixo kuphela kwaye ziluncedo ukujonga ukuba isitshixo sikhona na kwisingxobo, kodwa singabuyiseli ixabiso elinxulumeneyo. Izikhongozeli ezininzi zivumela ukugcina izitshixo eziphindiweyo ezininzi.

Zonke izikhongozeli ezisemgangathweni ezingacwangciswanga zisekwe kwi-node kwaye zisebenzisa i-Separate chaining ukujongana nokungqubana kwe-hash, okuthetha ukuba, zigcina isitshixo ngasinye okanye isitshixo sexabiso lesibini kwindawo yoluhlu oludityanisiweyo olwahlukileyo. Imemori yendawo nganye entsha yabelwe umntu ngamnye, nto leyo engasebenzi kakuhle. Oku kwenza ukuba ulwakhiwo lwedatha lungabi yi-CPU-cache-friendly, kuba ufikelelo ngalunye olungundoqo lufuna ulwalathiso olongezelelweyo. Nantsi indlela i unordered_map isakhiwo sangaphakathi esinokujongeka ngayo:

Ngakwesobunxele, kukho uluhlu lweebhakethi, olwabelwe kwangaphambili kumlinganiselo othile osisigxina ( 8 kumzekelo wethu). Ekuqaleni, zonke iibhakethi azinanto. Xa siqala ukongeza izinto kwimephu ye-hash, ezinye iibhakethi ziya kuhlala. Kulo mzekelo ungasentla, kukho into enesitshixo esingu- 10 (esingene kwi-emele 1 ), kunye neempawu ezimbini ezinezitshixo 50 kunye 256 , zombini ziphelele kwibhakethi enye yesi 3 kuba amaxabiso ehashi ayangqubana. Kukwakho into eneqhosha lesi - 3 , elithe lahlala kwibhakethi yesi 6 . Ibhakethi ngalinye lalatha kuluhlu oludityanisiweyo, oluqulathe ngokufanelekileyo into engekho ngaphezu kwesinye. Iibhakethi 0 , 2 , 4 , 5 , no 7 azinanto kwaye zikhomba kwi nullptr .

Makhe sicinge ukuba kufuneka sifumane ixabiso lesitshixo sama- 256 .

• Okokuqala, imephu ibala i-hash engundoqo kwaye ifumana intsalela xa isahlula ixabiso le-hash ngenani elipheleleyo leebhakethi ( 8 kwimeko yethu). Kumzekelo wethu, ixabiso eliseleyo ngu 3 .
• Emva koko, imephu iqala ukufunda izinto zoluhlu oludityanisiweyo olukhonjwe ngebhakethi 3 .
• Into yokuqala inesitshixo esingu 50 , esingafaniyo no- 256 esikhangelayo, ngoko ke imephu iya kuqhubeka ukuphinda-phinda. Into elandelayo inesitshixo 256 , eyilelo kanye esiyifunayo. Ixabiso elihambelanayo ngu xyz .
• Ukuba isitshixo besingekho kwisichazi-magama, imephu ibinokubetha i-emele engenanto okanye iphindaphinde kuluhlu oludityanisiweyo kude kube sekupheleni. Kuzo zombini ezi meko, imephu ingabuyisela end esichazayo, esibonisa ukuba isitshixo asikho.

Unokuqaphela ukuba inqaku lokugqibela loluhlu ngalunye lalatha kwinto yokuqala yoluhlu olulandelayo. Oku kwenziwa kwezinye iinkqubo zokuphumeza ukuphucula ukusebenza kakuhle kokuphindaphinda. Endaweni yokujonga ibhakethi ngebhakethi xa uphinda-phinda phezu kwayo yonke imephu yehash, sinokusebenzisa olo nxibelelwano ukutsiba ukusuka kuluhlu olungenanto oludityanisiweyo ukuya kolunye ngokukhawuleza okukhulu.

Ukuba siqhubeka nokongeza izinto kwimephu ye-hash engentla, ngaxa lithile into yomthwalo iya kuba phezulu kakhulu (umzekelo, 80%), kwaye imephu ye-hash iya kuthatha isigqibo sokuphinda ihoxise. Iza kukhulisa uluhlu olwabiwe kwangaphambili (umz. ukusuka kwisi 8 ukuya kwi 16 iielementi), buyisela i-hashes yazo zonke izinto ezikhoyo, kwaye ibeke izinto kwiibhakethi ezintsha.

Izikhongozeli ezisemgangathweni zibonelela ngereferensi kunye neziqinisekiso zozinzo eziphindaphindayo, kodwa zibuthathaka kunezo zinikezelwa zizikhongozeli ezi-odolweyo. Iimbekiselo kwiziqalelo ezikhoyo azinakuze zingasebenzi. I-Iterators kwiziqalelo esele zikho zinokwenziwa zingasebenzi kuphela xa udibaniso lwento entsha ibangela ukuphinda-phinda, okanye xa ukurehasha kwakhona kuqalwa ngesandla:

 #include <iostream> #include <unordered_map> int main() { std::unordered_map<std::string, int> map{ {"test", 123}, {"xyz", 456}, {"abc", 10} }; auto& value = map["abc"]; auto valueIt = map.find("abc"); // Might cause a rehash if the load factor // is too high map.emplace("zzz", 1000); // Triggers the rehash manually map.rehash(1000); // References remain valid in any case: std::cout << value << "\n"; // Iterators are invalidated: the line below // is undefined behavior and might crash std::cout << valueIt->second << "\n"; }

Ukusukela kwi-C++17, izikhongozeli ezingacwangciswanga zivumela ukuqhathwa kwe-node: kuyenzeka ukuba uthathe i-node kwimephu enye kwaye uyise kwenye imephu ngaphandle kokukopa isitshixo kunye nexabiso:

 #include <iostream> #include <unordered_map> int main() { std::unordered_map<std::string, int> map1{ {"test", 123}, {"xyz", 456}, {"abc", 10} }; // Take the node from map1: auto node = map1.extract("xyz"); // We can even change its key // (we can also change the value // if needed): node.key() = "xyzxyz"; std::unordered_map<std::string, int> map2; // Insert the node into another map: map2.insert(std::move(node)); // Prints "xyzxyz: 456": for (const auto& [k, v] : map2) { std::cout << k << ": " << v << "\n"; } }

Oku kwenzeka kule nkqubo ingentla:

Esinye isicwangciso sokujongana nokungqubana kwe-hash kuthiwa Vula idilesi . Kwiimephu ezineedilesi ezivulekileyo ze-hash, ibhakethi ngalinye ligcina eyona nto inye. Ukuba ibhakethi sele lihleli, into enexabiso elifanayo le-hash iya kwelinye ibhakethi lasimahla. Ezo mephu ze-hash zizama ukuhlanganisa izinto kwiibhloko zememori ezidityanisiweyo ukuphucula ukusebenza kakuhle kunye nokwenza ulwakhiwo lwedatha lube lula ngakumbi kwi-CPU cache. Ithala leencwadi eliqhelekileyo le-C++ aliboneleli ngeedilesi ezivulekileyo zeemephu zehash, kodwa zininzi iindlela ezizezinye zomntu wesithathu.

Iimephu ze-hash zomntu wesithathu

I-Boost.Unordered lithala leencwadi elimangalisayo elibonelela ngoluhlu olubanzi lokuphunyezwa kweemephu zehash.

Kukho boost::unordered_set , boost::unordered_map , boost::unordered_multiset , kwaye boost::unordered_multimap , ezizianalogu zezikhongozeli std , kwaye yonke into ebhaliweyo ngasentla iyasebenza kuzo. Ezi zikhongozeli zisebenzisa ubume obuntsonkothileyo bangaphakathi "namaqela amabhakethi" ukuphucula ukusebenza kakuhle kokuphindaphinda.

Ithala leencwadi likwabonelela boost::unordered_node_set , boost::unordered_node_map , boost::unordered_flat_set , kunye ne boost::unordered_flat_map , ezizikhongozeli zeedilesi ezivuliweyo. Ulwakhiwo lwangaphakathi lwahlukile kwiintlobo ngeentlobo zeedilesi ezivulekileyo:

Unokufunda ngakumbi malunga nesakhiwo sangaphakathi kule post blog .

Izikhongozeli ezisekelwe kwi-node ( boost::unordered_node_set , boost::unordered_node_map ) zisasebenzisa iindawo, ezikhonjwe ngamabhakethi. Ezi zikhongozeli zibonelela nge-iterator efanayo kunye nozinzo lwereferensi oluqinisekisiweyo njengezikhongozeli ze std kwaye zibonelela nge-API efanayo yokuguqulwa kwe-node (okt indlela extract ).

Kwizikhongozeli ezisicaba ( boost::unordered_flat_set , boost::unordered_flat_map ), izitshixo kunye namaxabiso agcinwa ngokuthe ngqo kuluhlu lwebhakethi. Izikhongozeli ezisicaba zezona zisebenza kakuhle, kodwa zinika ezona ziqinisekiso zibuthathaka: iziqinisekiso kunye neembekiselo kuzo zonke iindawo azivumelekanga xa ukuhanjwa kwakhona kusenzeka. Node manipulation API ayibonelelwanga kwaphela. Izikhongozeli ezimcaba zinokusebenzisa inkumbulo eninzi kunezo zisekwe kwindawo ekuyi node, ngakumbi ukuba isitshixo okanye sizeof bexabiso bukhulu.

Elinye ithala leencwadi lomntu wesithathu elisebenzisa izikhongozeli ezineedilesi ezivulekileyo yiFolly F14 (ebonelelwe yiMeta). Kukho iinguqulelo ezimbalwa zesichazi-magama ezisondele kakhulu kwizikhongozeli zethala leencwadi le-Boost ezichazwe ngasentla:

• folly::F14NodeSet iyafana ne boost::unordered_node_set , folly::F14NodeMap iyafana ne boost::unordered_node_map .
• folly::F14ValueSet iyafana boost::unordered_flat_set , kunye folly::F14ValueMap iyafana ne boost::unordered_flat_map .
• folly::F14VectorMap / folly::F14VectorSet gcina izitshixo/amaxabiso apakishwe kuluhlu oludityanisiweyo, kwaye amabhakethi aqulathe izalathisi kuloluhlu.
• folly::F14FastMap / folly::F14FastSet yiklasi yeambrela. Ikhetha olona phumezo lusebenzayo (ingaba F14Value okanye F14Vector ) ngokusekelwe kwiiparamitha ozikhankanyayo (ezifana nezitshixo kunye neentlobo zexabiso).

Into enomdla eyongezelelweyo esebenzayo yeemephu ze-F14 ze-hash ku -prehashing . Umzekelo, ukuba ufuna ukukhangela isitshixo esinye amaxesha amaninzi, kwaye i-hashing yayo iyabiza (umzekelo, isitshixo yintambo), ungayifaka kwangaphambili kube kanye, kwaye usebenzise i F14HashToken kuzo zonke iifowuni ze-hash emva kwexesha ukunqanda ukuphinda- Hashing iqhosha elifanayo amaxesha amaninzi. Indawo yokuqala yindlela ye prehash ( ikhonkco ).

Unokufunda ngakumbi malunga nolwakhiwo lwangaphakathi lwezikhongozeli ze-hash ze-F14 kule post ye-blog ye-FB .

Ithala leencwadi le-Abseil Swiss Tables (ebonelelwe nguGoogle) likwasebenzisa iidilesi ezivulekileyo ezisekelwe kwi-node-based kunye nezikhongozeli zehashi ezisicaba: absl::flat_hash_map , absl::flat_hash_set , absl::node_hash_map , absl::node_hash_set . Zifana ne-Boost kunye ne-F14. Unokufunda ngakumbi malunga nabo apha kwaye apha .

Ithala leencwadi ankerl elaziwayo kakhulu ( github ) libanga ukuba lisebenza kakhulu kwiimeko ezininzi. Umbhali weli thala leencwadi ubonelela ngeziphumo ezibanzi zebenchmark kwiimephu ezininzi ze-hash kwiimeko ezahlukeneyo zokusetyenziswa ( isithuba seblogi ). Unokulandela ezi ziphumo, kodwa zithathe ngengqolowa yetyuwa. Soloko uvavanya imephu ye-hash oyikhethayo kwindawo yemveliso. Ibenchmarks zisoloko zenziwe kwaye azikhuphi iimeko xa i-CPU kunye nememori zisenza omnye umsebenzi ngaphandle kwemisebenzi yemephu yehash. Iibenchmarks nazo aziwaquki iimeko xa iindawo ezahlukeneyo zememori yemephu ye-hash zingekho kwi-cache ye-CPU, eya kwenzeka rhoqo kwiinkqubo zokwenyani.

Umgangatho womsebenzi weHash

Umgangatho womsebenzi weHash ubalulekile ukugcina ukuntsonkotha kwexesha lemisebenzi yokujonga O(1) . Iimephu zehash ezisicaba zinobuntununtunu kumgangatho wokusebenza kwehashi. Umsebenzi we-hash ofanelekileyo unokuchazwa ngolu hlobo: ukuba isuntswana elinye kwisitshixo sitshintsha, ixabiso elihambelanayo le-hash liyakutshintsha isiqingatha samasuntswana alo ngokungakhethiyo. Umsebenzi onjalo we-hash ubizwa ngokuba yi-avalanching .

Ngelishwa, ukuphunyezwa kwethala leencwadi eliqhelekileyo le-C++ lenani elipheleleyo kunye nemisebenzi ye-hash yesalathi asiyiyo i-avalanching. Umzekelo, libstdc++ ibuyisela ngokulula isalathisi okanye ixabiso elipheleleyo ngokuthe ngqo ngaphandle kotshintsho olongezelelweyo: github .

Iitafile ze-hash eziphucukileyo, ezifana boost kunye nokuphunyezwa kwe F14 , jongana nalo mba ngokwazisa i hash_is_avalanching trait. Ukuba umsebenzi we-hash awuzichazi njenge-avalanching, itafile ye-hash iya kwenza inyathelo elongezelelweyo lokuxuba ukuphucula umgangatho we-hash. Oku kuza ngeendleko ezongezelelweyo. Ukuba uphumeza umsebenzi we-hash wesiko, kwaye uyazi ukuba ungowomgangatho ondilisekileyo, ungawuphawula ube shushu njengoko kubonisiwe kulo mzekelo . I-Boost isebenzisa is_avalanching igama lepropathi, kunye nepropati ye F14 ibizwa ngokuba folly_is_avalanching . Ngokufanelekileyo, kufuneka udibanise zombini.

Ukuba usebenzisa iintlobo ezingundoqo ezixhaswayo ngaphandle kwebhokisi (umzekelo, string , int , izikhombisi) kunye nemisebenzi ye-hash engagqibekanga enikezwe yi boost okanye F14 , ziya kuba sele ziphawulwe ngokuchanekileyo njengoko kufuneka, kwaye akuyi kufuneka ucinge ngale nto ngaphandle kokuba uthatha isigqibo sokuphumeza uhlobo lwesitshixo sesiko, oluya kufuna umsebenzi we-hash wesiko.

Ukhuseleko lomsonto

Zonke ezi zikhongozeli zingentla azikho intambo-ekhuselekileyo ngokubanzi, kwaye kuya kufuneka uphumeze ungqamaniso lwangaphandle (umzekelo, usebenzisa imutexes) ukuba intambo enye inokuguqula imephu yehash xa omnye umsonto ufikelela kuyo.

Ukuba yonke imisonto ifunda imephu kuphela, akukho lungqamaniso lufunekayo. Qinisekisa ukuba ubiza kuphela iindlela eziphawulwe nge const . Zonke iindlela const ezinokuthi zisiguqule isikhongozeli. Gcina ukhumbula ukuba operator[] akakho const kwaye uya kuguqula isikhongozeli. Umhadi oqhelekileyo kwikhowudi enemisonto emininzi ngulo:

 std::unordered_map<std::string, bool> map; // ... if (map["key"]) { // ... }

Kwikhowudi engentla, injongo kukukhangela ukuba ixabiso elihambelana key true . Nangona kunjalo, map["key"] iyakongeza key map ukuba ayikabikho. Ixabiso elitsha longezwa lizakumiselwa kokungagqibekanga ( false kulo mzekelo ungentla). Oku kuthetha ukuba, ikhowudi enjalo ayikhuselekanga ngomsonto, kwaye ayilunganga kakhulu. Indlela esebenzayo nekhuselekileyo yokujonga imeko efanayo yile ilandelayo:

 if (auto it = map.find("key"); it != map.end() && it->second == true) { // ... }

• Apha, siqala sifumana i-iterator kwinto echongiweyo nge "key".
• Emva koko sijonga ukuba into ikhona kwimephu ( it != map.end() ).
• Ukuba kunjalo, ekugqibeleni sijonga ixabiso layo ( it->second == true ).

Kulo mzekelo, find kwaye end musa ukuyiguqula imephu, kwaye uphendlo kuba imisonto-ekhuselekileyo. Ukuba injongo ibikukukhangela ukuba isitshixo sikhona na kwimephu, ungafowunela ngokulula map.contains("key") .

Iimephu ezingacwangciswanga ngemisonto ekhuselekileyo

Kukho umiliselo olumbalwa lweemephu zehashi ezikhuselekileyo.

• Olunye ukhetho lunyuso boost::concurrent_flat_set kunye boost::concurrent_flat_map esuka kwiBoost.Ilayibrari engacwangciswanga . Izikhongozeli zokunyusa zibonelela nge-API esekwe kutyelelo eyahluke kakhulu kwi-API ebonelelwa yilayibrari eqhelekileyo ye-C ++.
• Olunye ukhetho folly::ConcurrentHashMap ( github ). I-Folly izama ukugcina i-API yayo ikufutshane kangangoko kunokwenzeka kwizikhongozeli ze-C++ ezingacwangciswanga.
• i-libcds yithala leencwadi elikhulu elingenazitshixo elinesingxobo esibonelela ngomiliselo oluninzi lweemephu zehashi ezingatshixwanga (umzekelo MichaelHashMap , SkipListMap , SkipListSet , FeldmanHashMap , FeldmanHashSet ). Eli thala leencwadi alikahlaziywa kangangexesha elithile kwaye aliboneleli ngamaxwebhu aneenkcukacha, kodwa ndisabelana ngalo kuba izikhongozeli elizinikezelayo zahlukile. Ukuba imeko yakho yosetyenziso ithetha ukruthakruthwano oluphezulu kwimephu yehash, zama ezi zichazi-magama zingatshixwanga zinikelwe zii libcds .
• Ukuba ukusebenza kakuhle akuyongxaki, ungangqamanisa ufikelelo kwiimephu ezingakhuselekanga usebenzisa imutexes. Kungenjalo, unokukuphepha ngokupheleleyo ukufikelela ngaxeshanye, okuhlala kusebenza ngakumbi kunokusebenzisa izikhongozeli ezikhuselekileyo zomsonto okanye ukongeza ungqamaniso.

Ndisebenzisa eyiphi?

Makhe sijonge amanqaku ashwankathelweyo achaza indlela yokukhetha esona sikhongozeli sifanelekileyo.

• Ukuba ufuna ukudibanisa isitshixo kunye nexabiso, khetha imephu , kungenjalo, sebenzisa isethi .
• Ukuba kuyimfuneko ukugcina izitshixo eziphindwe kabini kwimephu, sebenzisa izikhongozeli ezininzi .
• Ukuba ufuna i-iterator engqongqo kunye neziqinisekiso zozinzo lwereferensi, sebenzisa std , boost , folly , okanye abseil node-based containers (ezifana ne std::unordered_map , boost::unordered_map , boost::unordered_node_map , okanye folly::F14NodeMap ). boost::unordered_node_... kwaye folly buya kuba kobona busebenza kakuhle.
• Ukuba i-iterator kunye nozinzo lwereferensi ayibalulekanga (oku kuthetha ukuba, awugcini iziphindaphindo, iimbekiselo, okanye izikhombisi kwimephu/ukuseta izinto ngaphandle okanye ungalindelanga ukuba zihlale zisemthethweni emva kokuba imephu ilungisiwe), emva koko khetha isikhongozeli esisicaba (esinjalo boost::unordered_flat_map okanye folly::F14FastMap ).
• Izikhongozeli ezimcaba zisebenzisa inkumbulo eninzi kunezo zisekwe kwindawo ekudityanwa kuzo, ngakumbi xa sizeof besitshixo kunye/okanye ixabiso likhulu. Ukuba usetyenziso lwememori yinkxalabo, sebenzisa izikhongozeli ezisekwe kwi-node endaweni yoko.
• Izikhongozeli ze-F14 zibonelela ngokusebenza kwangaphambili kokusebenza ngokufanelekileyo. Ukuba ukhangela/ukongeza/ususa izitshixo ezifanayo amaxesha amaninzi, F14 iyakwenza kube nokwenzeka ukugcina ixabiso le-hashing ngokuqalisa izitshixo.
• Onke la manqaku angasentla asebenza kusetyenziso lwesikhongozeli esinomsonto omnye (okanye ukufikelela kokufunda okunemisonto emininzi ngaphandle kohlengahlengiso olufanayo). Ukuba uhlengahlengiso oluneentambo ezininzi luyafuneka, khetha enye yeendlela ezikhuselekileyo ezidweliswe ngasentla. Bangabonisa ukusebenza okwahlukileyo kwikhowudi yokwenyani yokuvelisa, ngoko cinga ukubavavanya kwisicelo sakho kwaye uthelekise iziphumo.