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------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------stringphone;for(;;){cout

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*****cantreturntwodoubles,soweusedreferencevariables

intmain(){doubler;r:5doubleangle;angle:0...//getvaluesforrandangledoublex;x:5:xx//onceyoureturntothefunctionyoucantcallx...xxanymore.doubley;y:0:yypolarToCartesian(r,angle,x,y);//nowxandyhavetherihtvalues(wrongg)...doublex2;x2:10:xxpolarToCartesian(2*r,angle,x2,y);//wrong}

rho:10theta:0xx:yy:0------->doendupwiththerightvalues,butthesefourlocalvariablesgoawaywhenyouleavethefunctionvoidpolarToCartesian(doublerho,doubletheta,doublexx,doubleyy)//shouldbevoidpolarToCartesian(doublerho,doubletheta,double&x,double&y)//canalsobedouble&xx,double&yy

{x=rho*cos(theta);y=rho*sin(theta);}

Whydoesntthiswork?*****double&meansreference-doubleoranother-name-for-some-double******************canbedouble&xx,akaspaceasdesired*****cannotputacomputationintoareferencevariable-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

-------------------------k:(copy)3intsquare(intk)//preferablebecauseitismoreflexible{

returnk*k;}

voidsquareTheArgument(int&j){j*=j;}

intmain()

{intn;cin>>n;n:9intm;m:81...m=square(n);m=square(m);---------->thesquarefunctiondidntchangem,theassignmentdidcout

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...}---------------------------------------------------------------------------------------------------------::::FORPROJECT3::::---------------------------------------------------------------------------------------------------------inttraversePath(...,...,...,...,...,int&nsteps);//goalistoimplementtraversePathliketraverseSegment---------------------------------------------------------------------------------------------------------12n3eisavalidpath....12n3e123n3enotavalidpath*****pathsegmentsare1or2digitsfollowedbythedirectionlol*****78n3e78n3e,wellformedpathbutnottraversable12nemptystringisalsoawellformedpath,wontgoanywhere----------------------------------------------------------------------------------------------------------dothefunctionexerciseswootwootdothewriteuponcharactersandstringswootwoot-----------------------------------------------------------------------------------------------------------1n3eisnotapathsegment

@1ne3eisnotapathsegment----------------------------------------------------------------------------------------------------------::::TABLESMESASMESAS::::----------------------------------------------------------------------------------------------------------

boolisValidDate(inty,intm,intd){intdaysInMonth[12]={31,28,31,30,31,30,31,31,30,31,30,31};

...if(m12||dLEAVEEE...opposedtobreak,whichbreaksaloop/swi

tchstatementandcontinuewithrestoffunctionif(m==2){....return...;}returnd

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