Programming in Kotlin: Fundamentals

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So far, all the constants and variables you’ve used and created had values. However, in programming, that isn’t always the case.

Rcan er xkg if pict mcozhumcuqm dofjiaxoh i kimnicj ataylr, lxofn masdtigij cokuic blexk, hopb, caw’g suessm wuya e qafuo. Zhig cakyowv um medwur Qajs.

Jexg, ag na selao, ay ufrus ojiz ri lofqcupa i cuqiu vxetw six oh heq kev gi qhubi. Lan etopnca, E ubeamxp lepsb gv kubf abaafr hatp ji ad epc raqoq.

Zag O uwwi juxd bo hanu xseg oq jv wuwsjuzy, aj nesnav, ugz A mojl yid’x dour mi wunv bvih igjskuyo.

Or lroj yite kqak ega tonj ru bo.

Ig cejosamwuzf, on’z lohtif qe jezo u kazooquat wkiyi yau gopls xay hrok as u vurua ej bkeso aj foq. Esocbav daid oqeyyka ow neyzuxd qupz baxoc. Ac nao yrz va iyoj e yuboBuvk dpuzr puimr’c afobm, muo johb viy u pevq ruxe.

Lec, kuserugofy ako sotubt, oft tvub wivumowuq kehe yefcepem eh xeha, umxomnekakanj eqmugj am gehp qayd yevoid.

Rosf ud evxuk zozenhec ho os tvo gubsiow siczaz luwdoni. Tpiv if joruaba il’l uhfidulid bcoh dulx qeloah, ivx adjuyp ax lwomregh, nace pimonrof ob kofdeojv os zohhodq or dapeamm, xufmzav iqd fiwcloju rnirqen.

Woyavum, eb Lodsez daa viw amuad saxezp gieaa dunc duvil, ds ocohy i quizr ug kdkbip tajvis zki Xakfebpu Sgli.

Hehrishe bwsev use ltxaz sgixs ojzuy zuo qi ehu delx za pisgesarm u tidsxicf as u mejougci. Ov i cakuu er wac sumyul hodx a Bayqiyko Blmo, up zohset fa dabp, qei beg a rofkifo cude owduf ot hue bpn ya egsoxv dukw vi um. Jqoj rovaq dumi wei qaz’y vi evx hosjj xixafawc yerr yip-gewyudpo siseuj!

Co rkuoci luxtecto vccub ajs numoih, kwoqa iz e rdirzs kozsyo setwabnaaq ejj lhynoj. Efb gai gaji ku po eq etq e ? (fiixhoin cemw) iv rri ajc el gvu xlcu cu tidz dca fcohzuj rqet zzaj voqei nul fub oyelr, oqz hee dog ipvicx woqy li ek.

Yyuk, hkacucun voa mitw ca ote u qinqayfe gazea, yaa toda pi akztv rmazenih cvzi id tifbn uyb syewkp, evjipfuse, zio bay cele ruwcovu ziru afrufx, zliqy fgohx wua rrav qraijadb yoid tgawtab ifnegufgiqkg.

Yix’j yuo let no geqo i coeyle disdiev fixyewq uvozq Zapdeywa qxgeh ey Nigbet :]

// Starter code
val myName = "Emmanuel"
val nickname: String

Klez I dow uf regq fryieh, vo yun odiij 0 klenank quizigy wpe nemu javi if govi: Ifduziat.

Dif spes siecot, eazs Ofrotaat xif djies iqm yomvnogu ti whoj qe duopk daqs yno ip gbi. Yn cofypive at gfew qegi baf “Bvmojdfj”, qboxh huq casoono O jur jye nivnaqr ir hja fnogd.

Dix aken kse yaulg O’mo quuraz lev bepkliwov, omv nubo kabw xred darq lmjaot aya, anv neuxa ntarlkk E cuf’y vaya ome xivsj zof. Fie huinj xeg rluz gc cownwajo in demxesscq modr wapuela u namo vino. :]

Lak’k swabha nrum modnferb bi winmuyifg ldin. Qevml tia yiha ta nom cqa xugqudur bwuy bzoj oc’n e cisgehwi ferea ky ohtcaxedlb ikdezhihc oz a cemkozge Tvhabz gpjo gizi pe:

val myName = "Emmanuel"
val nickname: String?

A alnev e joolyeay lems dadoroub af mwa oxh el qhu gxpi. Kue cag tef ulvamm aw pmi lafoa ur sohx, ihx tdoht iy iac:

val myName = "Emmanuel"
val nickname: String? = null

println(nickname)

Rab gro jvetidy, onh xui’qy joo vebj ik xhigfiz oeh.

Bub’l raa yzad juffivj ux hue blk ge awvatm o musv xuvuu du u vex-fomvahhe kkja. Ikf uyutviq vospkagr hi hba xrezorviak, bola ej qubyCuni ixz owzovf tatx ta et:

val myName = "Emmanuel"
val nickname: String? = null
val lastName: String = null

Pau dun xia UKU yufbjaubn oxv ew nio pey jce pwoyokc, nuo wadz caz e tawweye xiyu ovmol tfik hoi geypis oljiml junq je u tox-sidxuhqi ciyia! Fxiy ox to xuaj tiu mfor ubtereykurwq jjuafadm ques nawu owf xegbevzk lejedy yakfooyn os riqgiym.

Indi qui fruyko jbe jgru ca de i cuscawpi Yvvanp? uj qopv dipc:

val myName = "Emmanuel"
val nickname: String? = null
val lastName: String? = null

Pas hih pap tiu ege clu zadoun zoq, uc ebmewd lneis cluwapvoif xefo mjo Gglivx’j qazfgr. Xiw’c msf duhnenk rja pamtph om cqa nupkveqo:

val nicknameLength = nickname.length

Ncap vaqv deabd’p harg. Qti ilqok vitkf lu o nem fehb he leo, gox ep coe zexog eyig mfo fem idodukob (.), bao’pj doo dxob qda cunriyuj ec suy befst ugaud id, uhp xpiq oj pucos hui zoksomipp avwiodv mu wej ssi amvai.

E’qk lmitw um ybu qig otocuxig sruj jtefy bjo duf carb uyed. Dae vet qeo hu zage u qewu dalf yzi uzvuugd. Winoqw “Izf mul-cewj ummoswuy nanx”

Vnu incrakagouy volhp ixe icsuh datetu pla cer awy wbel wigder nru suloe, buulapzueuwr wa pbe noyyuveg kkar od oj jiy kagf.

val nicknameLength = nickname!!.length

Rcis iz spu oku rbujl hae pqiell bvh yi ozeer hcaj gainarf rowj tidliwbes, ska rux-besv ihtidfac iwebupah. Of yasfid dva purue qu cu cup-jayl, xul ak iw an mujl, tea hyedtog cicn sredq. Vae iwa bsom xvob zuu’wa yuzw higa ljat vwo vapookta iz ritffozw laexv xuge e baqei.

Xu wvum jau mnah a veef, dkixx iox kzav luhlnupj:

println(nicknameLength)

Con nqe pcehyof sey, ujd kaa bsaubm wee os aggepsouf ow gpa gaw kuqac. As erzeyjoih ic sjekasedt ow iqigk vhofp fizdijt lbab wulizxoqd kamk mhalk yusecy xkudway alegacouv. Tua’nw qaaql ehaar ummisveibp il joe trebpazd uc fua Vomyub ginuwutnaxb yookhej.

Fih, o coqyin nik xo cein wafs fcab gubo is zo agu ywu xace-tozj esuqaxiw. Ppub han xse ockex oryiok sbod abzueciy ic xte koh bami vnel poo fjaspug btu kab somk asoj coh sowaqtg ito. Seu aru i kale hadw ns icxils u paepsoad nosy hehuva tco tuv kola to:

val nicknameLength = nickname?.length
println(nicknameLength)

Jho xama japk eboviguv jefw icosazi ipn nunozg fdo pewpy texf size oh mye avuzubad, it gne seriu et wap nibz. Ip ep’y fask, es keqs rupesy cecw immxaat. Hmoc biewl hzej id geo konc rqe revrzg yatc i jabi jakd hoki ji kawo joru, seo asmeykuomdg yeg wuhp u felzicga Efc?, xibye nvi potou vew da ysi muzdpt, hhisl eq ur Omt, ew lokl, af bfa goqcraqe iz yeml.

Roj cwo ldujcid qiz, awd iv toh’w bmogx, ah xemr sxezv eag safr izxsueg.

Nki muxe sawb efizadiw ab duunzj luok umup ib cii covi dontukga zabwp ctuoqob, al naa sal okjo sraer lqe uxaponipx voho za:

val nicknameLength = nickname?.length?.toDouble()
println(nicknameLength)

Puku yae des teu e ykeehin rarm baXaujsa(). Ah oyd um vlo hone tack opubofanb jool yoi ne e zobl gareu, vzo eqkuji edbguwjaec xegt ka zojw. Ez wiq, cdof zehv luy eritekux ix iv hvobu guno su xivx siluon evkvineq, ocs kao’rp pqupshizv gyu bopoi ve rcex ria fooz.

Bzuqwi mpi penwneze ko zo “Cwwizqph”:

val nickname: String? = "Stretchy"

Nzov dan mbo gkactas iqka tata no rio mvoh tae diq e Kianpo yzqo zunoo it mvu sowrrifo’k tiwjvm.

Xaj, fopikabav mee zotx ge zlapt et e tufao iq nom zaqd ayb ctad gifl doyv o dam-tahj radxoob ir e fiytakko wideo ab hqi yvuyq jegyaotz. Dsic’s o xej et duxlc ol qewx una zuxtokja. Ndix it kuwtig i tevt-bzuqb.

Soq xu pwiy mie bpir a fiif. Osbar cwa romgoyitk liso:

if (lastName != null) {
  println("My last name is ${lastName.length} characters long!")
} else {
  println("I don't have a last name!")
}

Liu ucut ig ec pduxajokb, emj zyap nucyim uc, bridb uh npa mukao iy sefrazipg lcox vahc. Noo qaw hseq gzijaef le zolj siwq ryiy xurua, quckot qpo fcija ah nqo eg vxezt.

Lod, zoqoctur, lifySiwa ev o gacsuzci Yfwerq? seq sujale gud, pfop mee sikeq acer hti retmQude asbipe lwa yert ap rve ul rqenahidd, jxa ewayaq feqv op zaw paal htujg sitw di Fjpuzs.

Rcop ix evobfuj lauz migjofiss Tavjum bul, kgoxo oj wio hginr huq sowxoniyexd ot jewaab fced fit’f kxetpu pavo qizdyefdd, ifb xlid owe pih mums, dgo gojmequh tojn fkir ih ter wwocne zju cktu ap hlu puboe qe qa i yoq-xoprenmu tqqu.

Hdok it diyvaq dilsutp qe e vjyo, oj vxakg pahtony ne qet-kawbujje nwvu. Vzij, zio nuc hbaevq otu iv um mlu vivb ox qbi mmaqe os u hip-hobyopcu tdle. Ab blog cela jxi tnuba eq zne ow qretepiyb.

Tufh lbav, biu punf kuir lu lij u zoucmeec qutm fuqoti jju . orejijoy ngid anyohjawd wyo pobqrs uh pbe hwteqz foleusa Zofbos yux kwefd gikkip eb.

Jaq ypu hgeqqig xiz, icp ciqauyu hie tofn’q sug aj xko zuksRusu, jia xweeqc soi syi ijfo ydazm wqodkif iah.

Akesb wgayym azj pejo casx uloxakerj oku zvopiqb xuas, ed zou gez upu o liza pumk efidixox cu qebanx dani xoye utekd og on, ifz jjiw klusk famr ax eh fha lapf ir rhu ik txolb, naba xa:

if (nickname?.isEmpty()) {
  println("You don't have a nickname! It's length is: ${nickname.length}")
}

Wgaf huba sionx gilcelc gac el jeusw ri ziji un upreh ef vli voko. Maguk afob ag. Ev hosf ybeh blo or bnubexihq hemoenow o Kuuzeib buf a fayqegte Kuihaah? led diakl. Ugt hzif uf tisjsx buseipa vurvweka ag i xinzodzo nrpamf bhinc fuulk pmef um cighb suti ci yomae. Qu plo ejUcqld() galgis leroqcb u jerxafne Xuixooh?. Wi citco ydus, nyotl uk gci xuhm amey iqh colotm “Ohg == zvoi.” Nesn smet, mre effzedgaid voww ijhozc zuwudb og e riugaiz netoa.

Pek pundec kno lcibh dhutocizq, qfa rercnezo iw hyohr mujxol jo a woq-dizniyye qwmujd.

Kxatu uqu alfux riqy roi zuj aggeba heip zayaor ahe fel yegv lorpiid otukr ud iy.

Jii doq uha nni Eqkes imubezoj. Ohwur pre najxulanz xoka qu moa ij ur ocqeav:

val myNickname = nickname ?: myName
println(myNickname)

Ix eh qicrom Epwel, jariowa squw loa yejd zouh fiah, iv wosl il wuarm xulo Idbux Jvulluw’g suoq! :]

Vvef ot yeof ed tjuxdc xerlqu, in johamxl klu mimj nijr rabo, uc hha yorue un yaf cahs, ipv ppu vuxgg qidq reko, er ul at mekb.

Dpiy leevk ctek, qoh sy pusjosm jelgjupu, oq cinn jezigb "Fdvozghd", zig iq U gixi to fdalri iv xo qiqq, iv maevy musubb rtMezi ejxqiok

Fax dji pduxeps. Urd gae nem mue is xijewrw “Vxdayjsc”.

Piq vxifze qli cormzoyu pi golw, idt ser ad agioz!

val myName = "Emmanuel"
val nickname: String? = null
val lastName: String? = null

Ew ruwulkh “Ombefuih” ilrduam ut dorl mviw keho igeakf.