C++复习资料1

C++复习资料1Fillintheblanksineachofthefollowing:a.Thecompanythatpopularizedpersonalcomputingwas_b.Thecomputerthatmadepersonalcomputinglegitimateinbusinessandindustrywasthe__IBMPersonalComputerc.Computersprocessdataunderthecontrolofsetsofinstructionscalledcomputer__programs_______.d.Thesixkeylogicalunitsofthecomputerarethe_inputunit_,__outputunit,__memoryunit__,_arithmeticandlogicunit__,_centralprocessingunit__andthe__secondarystorageunit___e.Thethreeclassesoflanguagesdiscussedinthechapterare_machinelanguages_,_assemblylanguages_,and__high-levellanguages__.f.Theprogramsthattranslatehigh-levellanguageprogramsintomachinelanguagearecalled___compilers___.g.Ciswidelyknownasthedevelopmentlanguageofthe_UNIX_operatingsystem.h.The_Pascal__languagewasdevelopedbyWirthforteachingstructuredprogramming.i.TheDepartmentofDefensedevelopedtheAdalanguagewithacapabilitycalled,whichallowsprogrammerstospecifythatmanyactivitiescanproceedinparallel.FillintheblanksineachofthefollowingsentencesabouttheC++environment.a.C++programsarenormallytypedintoacomputerusinga(n)program.b.InaC++system,a(n)__preprocessor__programexecutesbeforethecompiler'stranslationphasebegins.c.The_linker_programcombinestheoutputofthecompilerwithvariouslibraryfunctionstoproduceanexecutableimage.d.TheprogramtransferstheexecutableimageofaC++programfromdisktomemory.Fillintheblanksineachofthefollowingstatementsa.Objectshavethepropertyof__informationhiding_althoughobjectsmayknowhowtocommunicatewithoneanotheracrosswell-definedinterfaces,theynormallyarenotallowedtoknowhowotherobjectsareimplemented.b.C++programmersconcentrateoncreating_classes_,whichcontaindatamembersandthememberfunctionsthatmanipulatethosedatamembersandprovideservicestoclients.c.Classescanhaverelationshipswithotherclasses.Theserelationshipsarecalled__associations___.d.Theprocessofanalyzinganddesigningasystemfromanobject-orientedpointofviewiscalled__object-orientedanalysisanddesign(OOAD).___.e.OODalsotakesadvantageof_inheritance__relationships,wherenewclassesofobjectsarederivedbyabsorbingcharacteristicsofexistingclasses,thenaddinguniquecharacteristicsoftheirown.f.__TheUnifiedModelingLanguage(UML)__isagraphicallanguagethatallowspeoplewhodesignsoftwaresystemstouseanindustry-standardnotationtorepresentthem.g.Thesize,shape,colorandweightofanobjectareconsidered_attributes__oftheobject.Whyissomuchattentiontodayfocusedonobject-orientedprogrammingingeneralandC++inparticularANS1:Object-orientedprogrammingenablestheprogrammertobuildreusablesoftwarecomponentsthatmodelitemsintherealworld.Buildingsoftwarequickly,correctly,andeconomicallyhasbeenanelusivegoalinthesoftwareindustry.Themodular,object-orienteddesignandimplementationapproachhasbeenfoundtoincreaseproductivitywhilereducingdevelopmenttime,errors,andcost.ANS2:Inobject-orientedprogramming,thesourcecodeisorganizedinclassesandobjects,whichiseasytobemappingintotheitemsinphysicalworld.Itiseasytodesign,reuseandmaintainsuchkindofsoftwareinlargescalesoftwaredevelopment,whichisfavoredbythesoftwareindustry.【参考教材的 答案 八年级地理上册填图题岩土工程勘察试题省略号的作用及举例应急救援安全知识车间5s试题及答案 】面向对象的编程让编程者可以建立可重用的软件组件，这些组件是现实世界事物的抽象模型。软件工业的目标是快速、正确、有效率的开发软件。面向对象的 设计 领导形象设计圆作业设计ao工艺污水处理厂设计附属工程施工组织设计清扫机器人结构设计 和实现 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 模型已经被事实 证明 住所证明下载场所使用证明下载诊断证明下载住所证明下载爱问住所证明下载爱问 是可以提高生产效率和减少开发时间、错误和代价。【参考讲义的答案】面向对象的编程方法中，以类和对象来组织源代码，可以方便的实现与现实物理世界事物的映射。采用这种方法，易于在大型软件开发中进行软件的设计、重用和维护，因此受到软件行业的支持和采用。Youareprobablywearingonyourwristoneoftheworld'smostcommontypesofobjectsawatch.Discusshoweachofthefollowingtermsandconceptsappliestothenotionofawatch:object,attributes,behaviors,class,inheritance(consider,forexample,analarmclock),abstraction,modeling,messages,encapsulation,interface,informationhiding,datamembersandmemberfunctions.可能现在你的手腕上就戴着世界上最普遍的对象类型之一——手 表 关于同志近三年现实表现材料材料类招标技术评分表图表与交易pdf视力表打印pdf用图表说话 pdf 。论述以下这些术语和概念如何应用于手表这个概念上：对象、属性、行为、类、继承（例如，考虑闹钟）、封装、接口、信息隐藏、数据成员和成员函数。ANS:Theentirewatchisanobjectthatiscomposedofmanyotherobjects(suchasthemovingparts,theband,theface,etc.)Watchattributesaretime,color,band,style(digitaloranalog),etc.Thebehaviorsofthewatchincludesettingthetimeandgettingthetime,Awatchcanbeconsideredaspecifictypeofclock(ascananalarmclock),Withthatinmind,itispossiblethataclasscalledClockcouldexistfromwhichotherclassessuchaswatchandalarmclockcaninheritthebasicfeaturesintheclock.Thewatchisanabstractionofthemechanicsneededtokeeptrackofthetime.Theuserofthewatchdoesnotneedtoknowthemechanicsofthewatchinordertouseit;theuseronlyneedstoknowthatthewatchkeepsthepropertime.Inthissense,themechanicsofthewatchareencapsulated(hidden)insidethewatch.Theinterfacetothewatch(itsfaceandcontrolsforsettingthetime)allowstheusertosetandgetthetime.Theuserisnotallowedtodirectlytouchtheinternalmechanicsofthewatch.Allinteractionwiththeinternalmechanicsiscontrolledbytheinterfacetothewatch.Thedatamembersstoredinthewatcharehiddeninsidethewatchandthememberfunctions(lookingatthefacetogetthetimeandsettingthetime)providetheinterfacetothedata.Fillintheblanksineachofthefollowing.a.EveryC++programbeginsexecutionatthefunction_main_.b.The__leftbrace({)_beginsthebodyofeveryfunctionandthe__rightbrace(})_endsthebodyofeveryfunction.c.EveryC++statementendswitha(n)__semicolon_______.d.Theescapesequence\nrepresentsthe__character,whichcausesthecursortopositiontothebeginningofthenextlineonthescreen.e.The___statementisusedtomakedecisions.Statewhethereachofthefollowingistrueorfalse.Iffalse,explainwhy.Assumethestatementusingstd::cout;isused.a.Commentscausethecomputertoprintthetextaftertheb.Theescapesequence\n,whenoutputwithcoutandthestreaminsertionoperator,causesthecursortopositiontothebeginningofthenextlineonthescreen.c.Allvariablesmustbedeclaredbeforetheyareused.d.Allvariablesmustbegivenatypewhentheyaredeclared.e.C++considersthevariablesnumberandNuMbErtobeidentical.f.DeclarationscanappearalmostanywhereinthebodyofaC++function.g.Themodulusoperator(%)canbeusedonlywithintegeroperands.h.Thearithmeticoperators*,/,%,+andallhavethesamelevelofprecedence.i.AC++programthatprintsthreelinesofoutputmustcontainthreestatementsusingcoutandthestreaminsertionoperator.ANS:a.False.Commentsdonotcauseanyactiontobeperformedwhentheprogramisexecuted.Theyareusedtodocumentprogramsandimprovetheirreadability.b.True.c.True.d.True.e.False.C++iscasesensitive,sothesevariablesareunique.f.True.g.True.h.False.Theoperators*,/and%havethesameprecedence,andtheoperators+and–havealowerprecedence.i.False.Asinglecoutstatementwithmultiple\nescapesequencescanprintseverallinesWriteasingleC++statementtoaccomplisheachofthefollowing(assumethatusingdeclarationshavenotbeenused):a.Declarethevariablesc,thisIsAVariable,q76354andnumbertobeoftypeint.b.Prompttheusertoenteraninteger.Endyourpromptingmessagewithacolon(:)followedbyaspaceandleavethecursorpositionedafterthespace.c.Readanintegerfromtheuseratthekeyboardandstorethevalueenteredinintegervariableage.d.Ifthevariablenumberisnotequalto7,print"Thevariablenumberisnotequalto7".e.Printthemessage"ThisisaC++program"ononeline.f.Printthemessage"ThisisaC++program"ontwolines.EndthefirstlinewithC++.g.Printthemessage"ThisisaC++program"witheachwordonaseparateline.h.Printthemessage"ThisisaC++program"witheachwordseparatedfromthenextbyatab.ANS;a.intc,thisIsAVariable,q76354,number;b.std::cout<<"Enteraninteger:";c.std::cin>>age;d.if(number!=7)std::cout<<"Thevariablenumberisnotequalto7\n";e.std::cout<<"ThisisaC++program\n";f.std::cout<<"ThisisaC++\nprogram\n";g.std::cout<<"This\nis\na\nC++\nprogram\n";h.std::cout<<"This\tis\ta\tC++\tprogram\n";Writeastatement(orcomment)toaccomplisheachofthefollowing(assumethatusingdeclarationshavebeenused):a.Statethataprogramcalculatestheproductofthreeintegers.b.Declarethevariablesx,y,zandresulttobeoftypeint(inseparatestatements).c.Prompttheusertoenterthreeintegers.d.Readthreeintegersfromthekeyboardandstoretheminthevariablesx,yandz.e.Computetheproductofthethreeintegerscontainedinvariablesx,yandz,andassigntheresulttothevariableresult.f.Print"Theproductis"followedbythevalueofthevariableresult.g.Returnavaluefrommainindicatingthattheprogramterminatedsuccessfully.ANS:a.intx;inty;intz;intresult;c.cout<<"Enterthreeintegers:";d.cin>>x>>y>>z;e.result=x*y*z;f.cout<<"Theproductis"<7)cout<<"cisequaltoorgreaterthan7\n";ANS:a.Error:Semicolonaftertherightparenthesisoftheconditionintheifstatement.Correction:Removethesemicolonaftertherightparenthesis.[Note:Theresultofthiserroristhattheoutputstatementwillbeexecutedwhetherornottheconditionintheifstatementistrue.]Thesemicolonaftertherightparenthesisisanull(orempty)statementastatementthatdoesnothing.Wewilllearnmoreaboutthenullstatementinthenextchapter.b.Error:Therelationaloperator=>.Correction:Change=>to>=,andyoumaywanttochange"equaltoorgreaterthan"to"greaterthanorequalto"aswell.Fillintheblanksineachofthefollowing:a)______areusedtodocumentaprogramandimproveitsreadability.ANS:Commentsb)Theobjectusedtoprintinformationonthescreenis_____.ANS:coutc)AC++statementthatmakesadecisionis______.ANS:ifd)Mostcalculationsarenormallyperformedby______statements.ANS:assignmente)The______objectinputsvaluesfromthekeyboard.ANS:cinStatewhichofthefollowingaretrueandwhicharefalse.Iffalse,explainyouranswers.a)C++operatorsareevaluatedfromlefttoright.ANS:False.Someoperatorsareevaluatedfromlefttoright,whileotheroperatorsareevaluatedrighttoleft.b)Thefollowingareallvalidvariablenames:_under_bar_,m928134,t5,j7,her_sales,his_account_total,a,b,c,z,z2.ANS:True.c)Thestatementcout<<"a=5;";isatypicalexampleofanassignmentstatement.ANS:False.Thestatementisanoutputstatement.Thetexta=5;isoutputtothescreen.d)AvalidC++arithmeticexpressionwithnoparenthesesisevaluatedfromlefttoright.ANS:False.Arithmeticoperatorscanappearinanyorderinanexpression,soacounterexampleisa=b+c*d;whoseoperatorsareactuallyevaluatedfromrighttoleftbecauseoftherulesofoperatorprecedence.e)Thefollowingareallinvalidvariablenames:3g,87,67h2,h22,2h.ANS:False.h22isavalidvariablename.What,ifanything,printswheneachofthefollowingC++statementsisperformedIfnothingprints,thenanswer“nothing.”Assumex=2andy=3.a)cout<>x>>y;ANS:nothing.h)i)cout<<"\n";ANS:Anewlineisoutputwhichpositionsthecursoratthebeginningofthenextlineonthescreen.StatetheorderofevaluationoftheoperatorsineachofthefollowingC++statementsandshowthevalueofxaftereachstatementisperformed.a)x=7+3*6/2-1;ANS:*,/,+,-,=,15b)x=2%2+2*2-2/2;ANS:%,*,/,+,-,=,3c)x=(3*9*(3+(9*3/(3))));ANS:innermostparenthesesaround3,*,/,+,*,*,324Fillintheblanksineachofthefollowing:a)Ahouseistoablueprintasa(n)_________istoaclass.ANS:objectb)Everyclassdefinitioncontainskeyword_________followedimmediatelybytheclass'sname.ANS:classc)Aclassdefinitionistypicallystoredinafilewiththe_________filenameextension.ANS:.hd)Eachparameterinafunctionheadershouldspecifybotha(n)_________anda(n)_________.ANS:type,namee)Wheneachobjectofaclassmaintainsitsowncopyofanattribute,thevariablethatrepresentstheattributeisalsoknownasa(n)_________.ANS:datamemberf)Keywordpublicisa(n)_________.ANS:accessspecifierg)Returntype_________indicatesthatafunctionwillperformataskbutwillnotreturnanyinformationwhenitcompletesitstask.ANS:voidh)Function_________fromthelibraryreadscharactersuntilanewlinecharacterisencountered,thencopiesthosecharactersintothespecifiedstring.ANS:getlinei)Whenamemberfunctionisdefinedoutsidetheclassdefinition,thefunctionheadermustincludetheclassnameandthe_________,followedbythefunctionnameto"tie"thememberfunctiontotheclassdefinition.ANS:binaryscoperesolutionoperator(::)j)Thesource-codefileandanyotherfilesthatuseaclasscanincludetheclass'sheaderfileviaan_________preprocessordirective.ANS:#includeStatewhethereachofthefollowingistrueorfalse.Iffalse,explainwhy.a.Byconvention,functionnamesbeginwithacapitalletterandallsubsequentwordsinthenamebeginwithacapitalletter.b.Emptyparenthesesfollowingafunctionnameinafunctionprototypeindicatethatthefunctiondoesnotrequireanyparameterstoperformitstask.c.Datamembersormemberfunctionsdeclaredwithaccessspecifierprivateareaccessibletomemberfunctionsoftheclassinwhichtheyaredeclared.d.Variablesdeclaredinthebodyofaparticularmemberfunctionareknownasdatamembersandcanbeusedinallmemberfunctionsoftheclass.e.Everyfunction'sbodyisdelimitedbyleftandrightbraces({and}).f.Anysource-codefilethatcontainsintmain()canbeusedtoexecuteaprogram.g.Thetypesofargumentsinafunctioncallmustmatchthetypesofthecorrespondingparametersinthefunctionprototype'sparameterlist.ANS:a)False.Byconvention,functionnamesbeginwithalowercaseletterandallsubsequentwordsinthenamebeginwithacapitalletter.b)True.c)True.d)False.Suchvariablesarecalledlocalvariablesandcanbeusedonlyinthememberfunctioninwhichtheyaredeclared.e)True.f)True.g)True.WhatisthedifferencebetweenalocalvariableandadatamemberANS:Alocalvariableisdeclaredinthebodyofafunctionandcanbeusedonlyfromthepointatwhichitisdeclaredtotheimmediatelyfollowingclosingbrace.Adatamemberisdeclaredinaclassdefinition,butnotinthebodyofanyoftheclass'smemberfunctions.Everyobject(instance)ofaclasshasaseparatecopyoftheclass'sdatamembers.Also,datamembersareaccessibletoallmemberfunctionsoftheclass.Explainthepurposeofafunctionparameter.WhatisthedifferencebetweenaparameterandanargumentANS:Aparameterrepresentsadditionalinformationthatafunctionrequirestoperformitstask.Eachparameterrequiredbyafunctionisspecifiedinthefunctionheader.Anargumentisthevaluesuppliedinthefunctioncall.Whenthefunctioniscalled,theargumentvalueispassedintothefunctionparametersothatthefunctioncanperformitstask.Explainthedifferencebetweenafunctionprototypeandafunctiondefinition.ANS:Afunctionprototypetellsthecompilerthenameofafunctionandthetypeofdatareturnedbythefunction.Aprototypealsodescribesanyadditionaldatarequiredbythefunctiontoperformitstask.,thefunction’sparameters).Aprototypedoesnotcontaincodetomakethefunctionperformthetask—itmerelyoutlinesthefunctionsothatthecompilercanverifythatprogramscallthefunctioncorrectly.Afunctiondefinitioncontainstheactualcodethatexecutestoperformthefunction’sspecifiedtaskwhenthefunctioniscalled.Parameternamesarerequiredinthefunctiondefinitionandoptionalinthefunctionprototype.WhatisadefaultconstructorHowareanobject’sdatamembersinitializedifaclasshasonlyanimplicitlydefineddefaultconstructorANS:Adefaultconstructoristheconstructorthatiscalledwhenaprogrammercreatesanobjectwithoutspecifyinganyargumentstoaconstructor.Theprogrammercanwriteadefaultconstructorthatinitializesdatamembersanywaytheprogrammerchooses.Thecompilerprovidesadefaultconstructorwithnoparametersinanyclassthatdoesnotexplicitlyincludeaconstructor.Thedefaultconstructorprovidedbythecompilercreatesanobjectwithoutassigninganyinitialvaluestotheobject’sdatamembers—datamembersmustbeinitializedusingtheobject’smemberfunctions.Everyconstructorimplicitlycallstheconstructorsofanydatamemberobjectsbeforethebodyoftheclass’sconstructorexecutes.定义了默认构造函数的类的例子classBook1{public:Book1(){name=“(empty)”;}private:stringname;};没有定义默认构造函数的类的例子classBook2{private:stringname;};如果创建对象时，没有提供任何参数，C++将调用该类的默认构造函数创建该类的一个对象。intmain(){Book1sampleBook1;ANS:Aheaderfiletypicallycontainsaclassdefinition,inwhichthememberfunctionsanddatamembersoftheclassaredeclared(functionprototypesarefunctiondeclarations).Asource-codefileistypicallyusedtoprovidethedefinitionsofthememberfunctionsdeclaredintheclass’sheaderfile.Explainwhyaclassmightprovideasetfunctionandagetfunctionforadatamember.ANS:Adatamemberistypicallydeclaredprivateinaclasssothatonlythememberfunctionsoftheclassinwhichthedatamemberisdeclaredcanmanipulatethevariable,Aclasstypicallyprovidesasetfunctionandagetfunctionforadatamembertoallowclientsoftheclasstomanipulatethedatamemberinacontrolledmanner.Asetfunctionshouldvalidatethedataitissettingtoensurethatinvaliddataisnotplacedintheobject.Agetfunctioncanreturnthevalueofadatamemberwithoutallowingclientstointeractwiththedatamemberdirectly.Inaddition,setandgetfunctionshidetheinternaldatarepresentation.Forexample,aTimeclassmightrepresentthetimeasthetotalnumberofsecondssincemidnight.SuchaclasscanprovidememberfunctionsgetHour(),getingMinute()andgetSecond()tocalculatethehour,minuteandsecond，respectively—eveniftheunderlyingdatarepresentationdoesnotcontainhour,minuteandseconddatamembers.Similarly,aTimeclasscouldprovidememberfunctionssetHours(),setMinute()andsetSecond()tosetthecurrenthour,minuteorsecondvalue,Thiswouldrequireeachsetfunctiontoperformcalculationsthatupdatethedatamembercontainingthetotalnumberofsecondssincemidnight.Answereachofthefollowingquestions.a.Allprogramscanbewrittenintermsofthreetypesofcontrolstructures:_Sequence_,__selection__and_repetition__.b.The__if...else__selectionstatementisusedtoexecuteoneactionwhenaconditionisTRueoradifferentactionwhenthatconditionisfalse.c.Repeatingasetofinstructionsaspecificnumberoftimesiscalled_Counter-controlledordefinite__repetition.d.Whenitisnotknowninadvancehowmanytimesasetofstatementswillberepeated,a(n)_Sentinel,signal,flagorcanbeusedtoterminatetherepetition.WritefourdifferentC++statementsthateachadd1tointegervariablex.ANS:x=x+1;x+=1;++x;x++;WriteC++statementstoaccomplisheachofthefollowing:a.Inonestatement,assignthesumofthecurrentvalueofxandytozandpostincrementthevalueofx.b.Determinewhetherthevalueofthevariablecountisgreaterthan10.Ifitis,print"Countisgreaterthan10."c.Predecrementthevariablexby1,thensubtractitfromthevariabletotal.d.Calculatetheremainderafterqisdividedbydivisorandassigntheresulttoq.WritethisstatementtwodifferentwaysANS:.a.z=x+++y;b.if(count>10)cout<<"Countisgreaterthan10"<4usingstd::cout;5usingstd::endl;7intmain()8{intsum;Statethevaluesofeachvariableafterthecalculationisperformed.Assumethat,wheneachstatementbeginsexecuting,allvariableshavetheintegervalue5.a.product*=x++;b.quotient/=++x;ANS:.a.product=25,x=6;b.quotient=0,x=6;WritesingleC++statementsthatdothefollowing:a.Inputintegervariablexwithcinand>>.b.Inputintegervariableywithcinand>>.c.Setintegervariableito1.d.Setintegervariablepowerto1.e.Multiplyvariablepowerbyxandassigntheresulttopower.f.Postincrementvariableiby1.g.Determinewhetheriislessthanorequaltoy.h.Outputintegervariablepowerwithcoutand<<.ANS:a.cin>>x;b.cin>>y;c.i=1;d.power=1;e.power*=x;orpower=power*x;f.i++;g.if(i<=y)h.cout<4usingstd::cout;5usingstd::cin;6usingstd::endl;8intmain()9{intx;while(c<=5){product*=c;c++;b.cin<>.c.Error:Semicolonafterelseresultsinalogicerror.Thesecondoutputstatementwillalwaysbeexecuted.Correction:Removethesemicolonafterelse.Whatiswrongwiththefollowingwhilerepetitionstatementwhile(z>=0)sum+=z;ANS:Thevalueofthevariablezisneverchangedinthewhilestatement.Therefore,iftheloopcontinuationcondition(z>=0)isinitiallyTRue,aninfiniteloopiscreated.Topreventtheinfiniteloop,zmustbedecrementedsothatiteventuallybecomeslessthan0.WriteaC++programthatusesawhilestatementandthetabescapesequence\ttoprintthefollowingtableofvalues:编写一个C++程序，使用一个while语句和制表符的转义序列“\t”，打印下来。N10*N100*N1000*N11010010002202002000330300300044040040005505005000ANS:#includeusingstd::cout;usingstd::endl;intmain(){intn=1;NotethatthecompilerignorestheindentationinaC++program.TheC++compileralwaysassociatesanelsewiththep