graduate program department of computer science ......department of computer science comprehensive...

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1 Graduate Program Department of Computer Science Comprehensive Examination – Practice Questions CMPS 500 – Operating Systems 1. In what way is an operating system like a government? A) It seldom functions correctly. B) It creates an environment within which other programs can do useful work. C) It performs most useful functions by itself. D) It is always concerned primarily with the individual's needs. 2. ____ operating systems are designed primarily to maximize resource utilization. A) PC B) Handheld computer C) Mainframe D) Network 3. The most common secondary storage device is ____. A) random access memory B) solid state disks C) tape drives D) magnetic disk 4. Which of the following would lead you to believe that a given system is an SMP-type system? A) Each processor is assigned a specific task. B) There is a boss–worker relationship between the processors. C) Each processor performs all tasks within the operating system. D) None of the above 5. What statement concerning privileged instructions is considered false? A) They may cause harm to the system. B) They can only be executed in kernel mode. C) They cannot be attempted from user mode. D) They are used to manage interrupts. 6. Which of the following statements is false? A) Mobile devices must be concerned with power consumption. B) Mobile devices can provide features that are unavailable on desktop or laptop computers. C) The difference in storage capacity between a mobile device and laptop is shrinking. D) Mobile devices usually have fewer processing cores than a standard desktop computer.

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    GraduateProgramDepartmentofComputerScience

    ComprehensiveExamination–PracticeQuestions

    CMPS500–OperatingSystems

    1.Inwhatwayisanoperatingsystemlikeagovernment?A)Itseldomfunctionscorrectly.B)Itcreatesanenvironmentwithinwhichotherprogramscandousefulwork.C)Itperformsmostusefulfunctionsbyitself.D)Itisalwaysconcernedprimarilywiththeindividual'sneeds.2.____operatingsystemsaredesignedprimarilytomaximizeresourceutilization.A)PCB)HandheldcomputerC)MainframeD)Network3.Themostcommonsecondarystoragedeviceis____.A)randomaccessmemoryB)solidstatedisksC)tapedrivesD)magneticdisk4.WhichofthefollowingwouldleadyoutobelievethatagivensystemisanSMP-typesystem?A)Eachprocessorisassignedaspecifictask.B)Thereisaboss–workerrelationshipbetweentheprocessors.C)Eachprocessorperformsalltaskswithintheoperatingsystem.D)Noneoftheabove5.Whatstatementconcerningprivilegedinstructionsisconsideredfalse?A)Theymaycauseharmtothesystem.B)Theycanonlybeexecutedinkernelmode.C)Theycannotbeattemptedfromusermode.D)Theyareusedtomanageinterrupts.6.Whichofthefollowingstatementsisfalse?A)Mobiledevicesmustbeconcernedwithpowerconsumption.B)Mobiledevicescanprovidefeaturesthatareunavailableondesktoporlaptopcomputers.C)Thedifferenceinstoragecapacitybetweenamobiledeviceandlaptopisshrinking.D)Mobiledevicesusuallyhavefewerprocessingcoresthanastandarddesktopcomputer.

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    7.A(n)________istheunitofworkinasystem.A)processB)operatingsystemC)timerD)modebit8.ThetwoseparatemodesofoperatinginasystemareA)supervisormodeandsystemmodeB)kernelmodeandprivilegedmodeC)physicalmodeandlogicalmodeD)usermodeandkernelmode9.A_____isanexampleofasystemsprogram.A)commandinterpreterB)WebbrowserC)textformatterD)databasesystem10.Ifaprogramterminatesabnormally,adumpofmemorymaybeexaminedbya____todeterminethecauseoftheproblem.A)moduleB)debuggerC)shellD)controlcard11.Amessage-passingmodelis____.A)easiertoimplementthanasharedmemorymodelforintercomputercommunicationB)fasterthanthesharedmemorymodelC)anetworkprotocol,anddoesnotapplytooperatingsystemsD)onlyusefulforsmallsimpleoperatingsystems12.Policy____.A)determineshowtodosomethingB)determineswhatwillbedoneC)isnotlikelytochangeacrossplacesD)isnotlikelytochangeovertime13.______isamobileoperatingsystemdesignedfortheiPhoneandiPad.A)MacOSXB)AndroidC)UNIXD)iOS14.The________providesaportionofthesystemcallinterfaceforUNIXandLinux.A)POSIX

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    B)JavaC)StandardClibraryD)StandardAPI15.Whichofthefollowingstatementsisincorrect?A)Anoperatingsystemprovidesanenvironmentfortheexecutionofprograms.B)Anoperatingsystemmanagessystemresources.C)Operatingsystemsprovidebothcommandlineaswellasgraphicaluserinterfaces.D)Operatingsystemsmustprovidebothprotectionandsecurity.16._____is/arenotatechniqueforpassingparametersfromanapplicationtoasystemcall.A)CachememoryB)RegistersC)StackD)Specialblockinmemory17.The____ofaprocesscontainstemporarydatasuchasfunctionparameters,returnaddresses,andlocalvariables.A)textsectionB)datasectionC)programcounterD)stack18.Aprocesscontrolblock____.A)includesinformationontheprocess'sstateB)storestheaddressofthenextinstructiontobeprocessedbyadifferentprocessC)determineswhichprocessistobeexecutednextD)isanexampleofaprocessqueue19.ThelistofprocesseswaitingforaparticularI/Odeviceiscalleda(n)____.A)standbyqueueB)devicequeueC)readyqueueD)interruptqueue20.The_____________referstothenumberofprocessesinmemory.A)processcountB)long-termschedulerC)degreeofmultiprogrammingD)CPUscheduler21.WhichofthefollowingisnotaprocesstypeintheChromebrowser?

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    A)Plug-inB)RendererC)SandboxD)Browser22.The________applicationistheapplicationappearingonthedisplayscreenofamobiledevice.A)mainB)backgroundC)displayD)foreground23.Aprocessthathasterminated,butwhoseparenthasnotyetcalledwait(),isknownasa________process.A)zombieB)orphanC)terminatedD)init24.The_______processisassignedastheparenttoorphanprocesses.A)zombieB)initC)mainD)renderer25.____isathreadlibraryforSolaristhatmapsmanyuser-levelthreadstoonekernelthread.A)PthreadsB)GreenthreadsC)SthreadsD)Javathreads26.Pthreadsrefersto____.A)thePOSIXstandard.B)animplementationforthreadbehavior.C)aspecificationforthreadbehavior.D)anAPIforprocesscreationandsynchronization.27.The____multithreadingmodelmultiplexesmanyuser-levelthreadstoasmallerorequalnumberofkernelthreads.A)many-to-onemodelB)one-to-onemodelC)many-to-manymodel

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    D)many-to-somemodel28.Cancellationpointsareassociatedwith____cancellation.A)asynchronousB)deferredC)synchronousD)non-deferred29._________involvesdistributingtasksacrossmultiplecomputingcores.A)ConcurrencyB)TaskparallelismC)DataparallelismD)Parallelism30.___________isaformulathatidentifiespotentialperformancegainsfromaddingadditionalcomputingcorestoanapplicationthathasaparallelandserialcomponent.A)TaskparallelismB)DataparallelismC)DatasplittingD)Amdahl'sLaw31.WhenOpenMPencountersthe#pragmaompparalleldirective,itA)constructsaparallelregionB)createsanewthreadC)createsasmanythreadsasthereareprocessingcoresD)parallelizesforloops32.GrandCentralDispatchhandlesblocksbyA)placingthemonadispatchqueueB)creatinganewthreadC)placingthemonadispatchstackD)constructingaparallelregion33.Aracecondition____.A)resultswhenseveralthreadstrytoaccessthesamedataconcurrentlyB)resultswhenseveralthreadstrytoaccessandmodifythesamedataconcurrentlyC)willresultonlyiftheoutcomeofexecutiondoesnotdependontheorderinwhichinstructionsareexecutedD)Noneoftheabove34.Aninstructionthatexecutesatomically____.A)mustconsistofonlyonemachineinstructionB)executesasasingle,uninterruptibleunitC)cannotbeusedtosolvethecriticalsectionproblem

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    D)Alloftheabove35.Acountingsemaphore____.A)isessentiallyanintegervariableB)isaccessedthroughonlyonestandardoperationC)canbemodifiedsimultaneouslybymultiplethreadsD)cannotbeusedtocontrolaccesstoathread'scriticalsections36.Amutexlock____.A)isexactlylikeacountingsemaphoreB)isessentiallyabooleanvariableC)isnotguaranteedtobeatomicD)canbeusedtoeliminatebusywaiting37.A___typepresentsasetofprogrammer-definedoperationsthatareprovidedmutualexclusionwithinit.A)transactionB)signalC)binaryD)monitor38.____________occurswhenahigher-priorityprocessneedstoaccessadatastructurethatiscurrentlybeingaccessedbyalower-priorityprocess.A)PriorityinversionB)DeadlockC)AraceconditionD)Acriticalsection39.Whatisthecorrectorderofoperationsforprotectingacriticalsectionusingmutexlocks?A)release()followedbyacquire()B)acquire()followedbyrelease()C)wait()followedbysignal()D)signal()followedbywait()40.Whatisthecorrectorderofoperationsforprotectingacriticalsectionusingabinarysemaphore?A)release()followedbyacquire()B)acquire()followedbyrelease()C)wait()followedbysignal()D)signal()followedbywait()41.Whichofthefollowingistrueofcooperativescheduling?A)Itrequiresatimer.

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    B)AprocesskeepstheCPUuntilitreleasestheCPUeitherbyterminatingorbyswitchingtothewaitingstate.C)Itincursacostassociatedwithaccesstoshareddata.D)Aprocessswitchesfromtherunningstatetothereadystatewhenaninterruptoccurs.42.____isthenumberofprocessesthatarecompletedpertimeunit.A)CPUutilizationB)ResponsetimeC)TurnaroundtimeD)Throughput43.____schedulingisapproximatedbypredictingthenextCPUburstwithanexponentialaverageofthemeasuredlengthsofpreviousCPUbursts.A)MultilevelqueueB)RRC)FCFSD)SJF44.The____schedulingalgorithmisdesignedespeciallyfortime-sharingsystems.A)SJFB)FCFSC)RRD)Multilevelqueue45.Therateofaperiodictaskinahardreal-timesystemis____,wherepisaperiodandtistheprocessingtime.A)1/pB)p/tC)1/tD)pt46.Whichofthefollowingistrueoftherate-monotonicschedulingalgorithm?A)Thetaskwiththeshortestperiodwillhavethelowestpriority.B)Itusesadynamicprioritypolicy.C)CPUutilizationisboundedwhenusingthisalgorithm.D)Itisnon-preemptive.47.Whichofthefollowingistrueofearliest-deadline-first(EDF)schedulingalgorithm?A)Whenaprocessbecomesrunnable,itmustannounceitsdeadlinerequirementstothesystem.B)Deadlinesareassignedasfollowing:theearlierthedeadline,thelowerthepriority;thelaterthedeadline,thehigherthepriority.C)Prioritiesarefixed;thatis,theycannotbeadjustedwhenanewprocessstartsrunning.D)Itassignsprioritiesstaticallyaccordingtodeadline.

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    48.Thetwogeneralapproachestoloadbalancingare__________and____________.A)softaffinity,hardaffinityB)coarsegrained,finegrainedC)softreal-time,hardreal-timeD)pushmigration,pullmigration49.Adeadlockedstateoccurswhenever____.A)aprocessiswaitingforI/OtoadevicethatdoesnotexistB)thesystemhasnoavailablefreeresourcesC)everyprocessinasetiswaitingforaneventthatcanonlybecausedbyanotherprocessinthesetD)aprocessisunabletoreleaseitsrequestforaresourceafteruse50.Onenecessaryconditionfordeadlockis____,whichstatesthatatleastoneresourcemustbeheldinanonsharablemode.A)holdandwaitB)mutualexclusionC)circularwaitD)nopreemption51.Onenecessaryconditionfordeadlockis______,whichstatesthataprocessmustbeholdingoneresourceandwaitingtoacquireadditionalresources.A)holdandwaitB)mutualexclusionC)circularwaitD)nopreemption52.Onenecessaryconditionfordeadlockis______,whichstatesthataresourcecanbereleasedonlyvoluntarilybytheprocessholdingtheresource.A)holdandwaitB)mutualexclusionC)circularwaitD)nopreemption53.Onenecessaryconditionfordeadlockis______,whichstatesthatthereisachainofwaitingprocesseswherebyP0iswaitingforaresourceheldbyP1,P1iswaitingforaresourceheldbyP2,andPniswaitingforaresourceheldbyP0.A)holdandwaitB)mutualexclusionC)circularwaitD)nopreemption54.Thewitnesssoftwareproductisa____.A)lock-orderverifierthatusesmutual-exclusionlockstoprotectcriticalsectionsB)modelertodevelopresourceallocationgraphs

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    C)driverthatcanbeusedtopreventmutualexclusionfornonsharableresourcesD)implementationofthebanker'salgorithmavailableformostoperatingsystems55.Inasystemresource-allocationgraph,____.A)adirectededgefromaprocesstoaresourceiscalledanassignmentedgeB)adirectededgefromaresourcetoaprocessiscalledarequestedgeC)adirectededgefromaprocesstoaresourceiscalledarequestedgeD)Noneoftheabove56.Acycleinaresource-allocationgraphis____.A)anecessaryandsufficientconditionfordeadlockinthecasethateachresourcehasmorethanoneinstanceB)anecessaryandsufficientconditionforadeadlockinthecasethateachresourcehasexactlyoneinstanceC)asufficientconditionforadeadlockinthecasethateachresourcehasmorethanonceinstanceD)isneithernecessarynorsufficientforindicatingdeadlockinthecasethateachresourcehasexactlyoneinstance57.Absolutecodecanbegeneratedfor____.A)compile-timebindingB)load-timebindingC)execution-timebindingD)interruptbinding58._____isthemethodofbindinginstructionsanddatatomemoryperformedbymostgeneral-purposeoperatingsystems.A)InterruptbindingB)CompiletimebindingC)ExecutiontimebindingD)Load-timebinding59.AnaddressgeneratedbyaCPUisreferredtoasa____.A)physicaladdressB)logicaladdressC)postrelocationregisteraddressD)Memory-ManagementUnit(MMU)generatedaddress60.Supposeaprogramisoperatingwithexecution-timebindingandthephysicaladdressgeneratedis300.Therelocationregisterissetto100.Whatisthecorrespondinglogicaladdress?A)199B)201

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    C)200D)30061.Consideralogicaladdresswithapagesizeof8KB.Howmanybitsmustbeusedtorepresentthepageoffsetinthelogicaladdress?A)10B)8C)13D)1262.Consideralogicaladdresswith18bitsusedtorepresentanentryinaconventionalpagetable.Howmanyentriesareintheconventionalpagetable?A)262144B)1024C)1048576D)1863.AssumeasystemhasaTLBhitratioof90%.Itrequires15nanosecondstoaccesstheTLB,and85nanosecondstoaccessmainmemory.Whatistheeffectivememoryaccesstimeinnanosecondsforthissystem?A)108.5B)100C)22D)176.564.Giventhelogicaladdress0xAEF9(inhexadecimal)withapagesizeof256bytes,whatisthepagenumber?A)0xAEB)0xF9C)0xAD)0x00F965.Whichofthefollowingisabenefitofallowingaprogramthatisonlypartiallyinmemorytoexecute?A)Programscanbewrittentousemorememorythanisavailableinphysicalmemory.B)CPUutilizationandthroughputisincreased.C)LessI/Oisneededtoloadorswapeachuserprogramintomemory.D)Alloftheabove66.Insystemsthatsupportvirtualmemory,____.A)virtualmemoryisseparatedfromlogicalmemory.B)virtualmemoryisseparatedfromphysicalmemory.C)physicalmemoryisseparatedfromsecondarystorage.D)physicalmemoryisseparatedfromlogicalmemory.

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    67.Thevfork()systemcallinUNIX____.A)allowsthechildprocesstousetheaddressspaceoftheparentB)usescopy-on-writewiththefork()callC)isnotintendedtobeusedwhenthechildprocesscallsexec()immediatelyaftercreationD)duplicatesallpagesthataremodifiedbythechildprocess68.Supposewehavethefollowingpageaccesses:12342341211314andthattherearethreeframeswithinoursystem.UsingtheFIFOreplacementalgorithm,whatisthenumberofpagefaultsforthegivenreferencestring?A)14B)8C)13D)1069.Supposewehavethefollowingpageaccesses:12342341211314andthattherearethreeframeswithinoursystem.UsingtheFIFOreplacementalgorithm,whatwillbethefinalconfigurationofthethreeframesfollowingtheexecutionofthegivenreferencestring?A)4,1,3B)3,1,4C)4,2,3D)3,4,270.Supposewehavethefollowingpageaccesses:12342341211314andthattherearethreeframeswithinoursystem.UsingtheLRUreplacementalgorithm,whatisthenumberofpagefaultsforthegivenreferencestring?A)14B)13C)8D)1071.Giventhereferencestringofpageaccesses:12342341211314andasystemwiththreepageframes,whatisthefinalconfigurationofthethreeframesaftertheLRUalgorithmisapplied?A)1,3,4B)3,1,4C)4,1,2D)1,2,372.Belady'sanomalystatesthat____.A)givingmorememorytoaprocesswillimproveitsperformanceB)asthenumberofallocatedframesincreases,thepage-faultratemaydecreaseforallpagereplacementalgorithms

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    C)forsomepagereplacementalgorithms,thepage-faultratemaydecreaseasthenumberofallocatedframesincreasesD)forsomepagereplacementalgorithms,thepage-faultratemayincreaseasthenumberofallocatedframesincreases73.IntheUNIXoperatingsystem,adomainisassociatedwiththe____.A)userB)processC)procedureD)task74.InMULTICS,theprotectiondomainsareorganizedina_____.A)starstructureB)linearstructureC)ringstructureD)directorystructure75.Inanaccessmatrix,the____rightallowsaprocesstochangetheentriesinarow.A)ownerB)copyC)control.D)switch76.The____implementationofanaccesstableconsistsofsetsoforderedtriples.A)globaltableB)accesslistforobjectsC)lock-keymechanismD)capabilitylist77.Incapabilitylists,eachobjecthasa____todenoteitstype.A)gateB)tagC)keyD)lock78.Whichofthefollowingimplementationsoftheaccessmatrixisacompromisebetweentwootherimplementationslistedbelow?A)accesslistB)capabilitylistC)globaltableD)lock-key79.Inthereacquisitionschemeforimplementingtherevocationofcapabilities,____.A)akeyisdefinedwhenthecapabilityiscreated

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    B)thecapabilitiespointindirectly,notdirectly,totheobjectsC)alistofpointersismaintainedwitheachobjectthatpointtoallcapabilitiesassociatedwiththatobjectD)capabilitiesareperiodicallydeletedfromeachdomain80.Themostcommonmethodusedbyattackerstobreachsecurityis____.A)masqueradingB)messagemodificationC)sessionhijackingD)phishing81.Acodesegmentthatmisusesitsenvironmentiscalled____.A)abackdoorB)atrapdoorC)awormD)aTrojanhorse82.Worms____.A)usethespawnmechanismtoravagesystemperformanceB)canshutdownanentirenetworkC)continuetogrowastheInternetexpandsD)Alloftheabove83.Adenialofserviceattackis____.A)aimedatgaininginformationB)aimedatstealingresourcesC)aimedatdisruptinglegitimateuseofasystemD)generallynotnetworkbased84.Inapaired-passwordsystem,____.A)theuserspecifiestwopasswordsB)thecomputersuppliesonepartofapasswordandtheuserenterstheotherpartC)passwordsmustcontainequalamountsofnumbersanddigitspairedtogetherD)twousersmustentertheirownseparatepasswordtogainaccesstothesystem85.A____viruschangeseachtimeitisinstalledtoavoiddetectionbyantivirussoftware.A)polymorphicB)tunnelingC)multipartiteD)stealth86.____isasymmetricstreamcipher.A)DES

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    B)AESC)RC4D)twofish87.Inavirtualmachine,eachprogrambelievesthatithas____.A)multipleprocessorsB)itsownmemoryC)another"virtual"computertoassistinitsoperationsD)morememorythanisphysicallyavailableonthemachine88.____isapopularcommercialapplicationthatabstractsIntel80XXx86hardwareintoisolatedvirtualmachines.A).NETB)JITC)JVMD)VMware89._____isnotanexampleofabenefitofvirtualmachines.A)TheabilitytorunseveraldifferentoperatingsystemsthatallsharethesamehardwareB)TheabilitytoconcurrentlyrunseveraldifferentoperatingsystemsC)UseslessphysicalmemorythananactualoperatingsystemD)Protectsthehostsystemfromguestoperatingsystems90.______tricksanapplicationbyhavingitthinkitistheonlyprocessonthesystem.A)ParavirtualizationB)SimulationC)TheJavavirtualmachineD)The.NETframework91._________allowsavirtualmachinetobehaveasifitisactinginkernelmode.A)ParavirtualizationB)LivemigrationC)Trap-and-emulateD)TheJavavirtualmachine92.Microsoft.NETandtheJavavirtualmachineareexamplesof__________.A)ParavirtualizationB)ProgrammingenvironmentvirtualizationC)EmulatorsD)Type0hypervisors93.WhichofthefollowingstatementsregardingavirtualCPU(VCPU)isconsideredfalse?A)TheVCPUdoesnotexecutecode.B)ItrepresentsthestateofthephysicalCPU.

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    C)EachguestsharestheVCPU.D)TheVCPUisfoundinmostvirtualizationoptions.94.Inadistributedsystem,a____usuallyindicatesthelocationofamachine.A)nodeB)hostC)siteD)resource95.____involvesthemovementofjobsfromonesitetoanothertodistributeprocessingmoreevenlyacrossthenetwork.A)ComputermigrationB)LoadsharingC)ResourcesharingD)Downsizing96.Thesftp___commandtransfersafilefromtheremotemachinetothelocalmachine.A)copyB)putC)getD)cd97.Whichofthefollowingroutingschemescannotadapttolinkfailuresorloadchanges?A)virtualroutingB)fixedroutingC)dynamicloadingD)Alloftheabove98.Whichofthefollowingconnectionstrategiesinvolvesbreakingupamessageintoanumberofpacketsthatmustbereassembleduponarrival?A)messageswitchingB)packetswitchingC)circuitswitchingD)processswitching99.WhichofthefollowinglayersofacommunicationsnetworkintheOSIprotocolisusedtohandleframes,orfixed-lengthpartsofpackets?A)networklayerB)physicallayerC)data-linklayerD)transportlayer100.Whichofthefollowingisnotconsideredabenefitofprocessmigration?A)Loadbalancing

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    B)SoftwareneutralityC)HardwarepreferenceD)Computationspeedup

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    CMPS501–ProgrammingLanguages

    1. Whichofthefollowingareobjectorientedlanguages?a. Javab. Cobolc. Cd. Allofabovee. Noneofabove

    2. Inprogramming,aseriesoflogicallyorderedstepsthatleadtoarequiredresultiscalleda. Acompilerb. Aprogramc. Adatastructured. Analgorithm

    3. WhichisatypicallanguageforprogramminginsideWebpages?a. javaScriptb. HTMLc. Cobold. XML

    4. Whichofthefollowingconvertssourcecodeintomachinecodeateachruntime?a. Linkerb. Compilerc. Interpreterd. Objetencoder

    5. Whichofthefollowingcommonlyhappenstovariables(inmostlanguages)?a. Expansionb. Derivationc. Assignmentd. Allofabovee. Noneofabove

    6. Assumingthat+and*arearithmeticoperators(additionandmultiplication),towhatdoestheexpression2+4*5+1evaluate?

    a. 36b. 31c. 26d. 23

    7. Assumingthat=and/aretheassignmentanddivisionoperators,whatwillbetheoutcomeofthefollowingcodeinmostprogramminglanguages:

    a. Syntaxerrorb. Runtimeerrorc. Logicerrord. Compilererror

    8. Whichisatypicalkindofvariableforkeepinganorderedsetofvaluesinmemory,thatcanbereferencedase.g.A[3],A[n+1]etc.?

    a. File

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    b. Stringc. Arrayd. container

    9. AND,ORandNOTarelogicaloperators.Whatdatatypeisexpectedfortheiroperands?a. Integerb. Booleanc. Decimald. Character

    10. Inmanyprogramminglanguages,‘otherwise’and‘else’arepartofwhichbuildingblock?a. Loopb. Counterc. Selectiond. Liststructure

    11. Whatbuildingblockdoesthefollowingdiagramrepresent?whilex<10 printx x=x+1

    a. Sequenceb. Selectionc. Functiond. Iteration

    12. Whichisaworkingsolutionforproducingthefollowingoutput:1491625?

    a. Ab. Bc. Cd. D

    13. Thefollowingisatypicalpatternforreadingandprocessingdatafromasequentialfile.Whatishiddenbehindthequestionmarks?

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    a. whilenotEOFb. ifcount=endc. countuntilendd. Noneofabove

    14. (Inmostprogramminglanguages),whichstatementwouldbeusedinthedefinitionofafunction,toindicatetheresultingvaluewhenthisfunctioniscalled?

    a. result=xb. replyxc. sendxd. returnx

    15. ‘Tracing’,‘stepping’and‘breakpoint’aretypicaltermsbelongingtowhichprogrammingdevelopmentaspect?

    a. projectplanningb. compilationc. debuggingd. versioncontrol

    16. Whichtermdescribesthemechanismofafunctioncallingitself?a. encapsulationb. recursionc. inheritanced. polymorphism

    17. Whatistheonlylanguagethatacomputerunderstandsdirectly?a. English,asspokeninBoston,Mass.b. BASICtheBeginners’All-purposeSymbolicInstructionCodec. machinelanguage,differentforeverytypeofCPUd. noneofabove

    18. Whatarethethreemaintypesofcomputerprogramminglanguages?a. Machinelanguage,assemblylanguage,highlevellanguageb. Imperativelanguage,functionallanguage,declarativelanguagec. COBOL,Fortran-77,C++d. Noneofabove

    19. Fromthepointofviewoftheprogrammerwhatarethemajoradvantagesofusingahigh-levellanguageratherthaninternalmachinecodeorassemblerlanguage?

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    a. Efficiencyb. Programportabilityc. Easydevelopmentd. Noneofabove

    20. Aliasinginthecontextofprogramminglanguagesreferstoa. multiplevariableshavingthesamememorylocationb. multiplevariableshavingthesamevaluec. multiplevariableshavingthesameidentifierd. multipleusesofthesamevariable

    21. WhatisprintedbytheprintstatementsintheprogramP1assumingcallbyvalueparameterpassing?

    ProgramPl(){x=10;y=3;func1(y,x,x);printx;printy;}func1(x,y,z){y=y+4;z=x+y+z;}

    a. 10,3b. 31,3c. 27,7d. Noneoftheabove

    22. Considerthefollowingprogram

    ProgramP2varn:int:procedureW(varx:int)beginx=x+1;printx;endprocedureDbeginvarn:int;n=3;

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    W(n);endbegin//beginP2n=10;D;endIfthelanguagehasdynamicscopingandparametersarepassedbyreference,whatwillbeprintedbytheprogram?

    a. 10b. 11c. 3d. Noneoftheabove

    23. The-resultsreturnedbyfunctionsundervalue-resultandreferenceparameterpassingconventions

    a. Donotdifferb. Differinthepresenceofloopsc. Differinallcasesd. Maydifferinthepresenceofexceptions

    24. WhatisprintedbytheprintstatementsintheprogramP1assumingcallbyvalueparameterpassing?

    ProgramPl(){x=10;y=3;func1(y,x);printx;printy;}func1(x,y){y=y+4;x=2*x+y;}

    a. 10,3b. 14,20c. 4,4d. Noneoftheabove

    25. WhatisprintedbytheprintstatementsintheprogramP1assumingcallbyreferenceparameterpassing?

    ProgramPl(){

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    x=10;y=3;func1(y,x);printx;printy;}func1(x,y){y=y+4;x=2*x+y;}

    a. 10,3b. 14,20c. 4,4d. Noneoftheabove

    26. WhatisprintedbytheprintstatementsintheprogramP1assumingcallbyresultparameterpassing?

    ProgramPl(){x=10;y=3;func1(y,x);printx;printy;}func1(x,y){y=y+4;x=2*x+y;}

    a. 10,3b. 14,20c. 4,4d. Noneoftheabove

    27. WhatisprintedbytheprintstatementsintheprogramP1assumingcallbyvalue-resultparameterpassing?

    ProgramPl(){x=10;y=3;func1(y,x);printx;

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    printy;}func1(x,y){y=y+4;x=2*x+y;}

    a. 10,3b. 14,20c. 4,4d. Noneoftheabove

    28. WhatisprintedbytheprintstatementsintheprogramP1assumingcallbynameparameterpassing?

    ProgramPl(){x=10;y=3;func1(y,x);printx;printy;}func1(x,y){y=y+4;x=2*x+y;}

    a. 10,3b. 14,20c. 4,4d. Noneoftheabove

    29. Whichfollowingterm(s)isnotaPLprogrammingparadigm?a. Imperativeb. Functionalc. Logicald. hierarchical

    30. Whichfeature(s)isnotamistakemadebyapastPL?a. Spacesinvariablenamesb. Non-reservedkeywordsc. Callbreferenced. 2-digitrepresentationofyear

    31. WhatisthefullformofLISP?a. LightProcessingb. ListProcessing

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    c. LikeProcessingd. Noneoftheabove

    32. Whatistheoutputofthefollowingstatement?(CAR‘(PHW))

    a. Pb. Hc. Wd. PHW

    33. Whatistheoutputofthefollowingstatement?(CADAR‘((ab)(cd)))

    a. ab. bc. cd. d

    34. Whatistheoutputofthefollowingstatement?(cdr‘(abc))

    a. ab. bc. (bc)d. Noneoftheabove

    35. Whichallowprocedurestousethemselvesagain?a. Recursionb. Reusec. Reinitiated. Noneoftheabove

    36. Theleftsideofanassignmentstatementwillhold:a. avariableb. anobjectpropertyc. anexpressiond. Bothaandbe. Alloftheabove

    37. Therightsideofanassignmentstatementwillhold:a. avariableb. anobjectpropertyc. anexpressiond. Bothaandbe. Alloftheabove

    38. Whatisaprocedurethatreturnsavaluethatsignalstrueorfalse?a. Listb. Predicatesc. Datad. Noneoftheabove

    39. Whatistheoutputofthegivenstatement?(equal(+22)3)

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    a. Tb. NILc. Fd. Bothb&c

    40. Whichnotationfacilitatesuniformityinlisp?a. Prefixb. Postfixc. Infixd. Noneoftheabove

    41. Whichisaproceduressuppliedbyuserintermsofprimitives?a. Customb. User-definedc. Definited. Alloftheabove

    42. Whatistheoutputofthefollowingstatement?(+3.142.71)

    a. 3.14b. 2.71c. 5.85d. Noneoftheabove

    43. Whatistheoutputofthegivenstatement?(progn(setfa‘x)(setfb‘y)(Setfc‘z))

    a. Xb. Yc. Zd. XYZ

    44. Whatistheoutputofthegivenstatement?(setfprecious‘(time)‘(Timeisprecious)

    a. Timeispreciousb. Timeistimec. Timed. Noneoftheabove

    45. WhichofthefollowingSchemeexpressionswouldbeinterpretedasfalsewhenevaluated:

    a. NILb. –1c. (CAR‘(01))d. ‘()e. noneoftheabove

    46. Whichofthefollowingisnotconsideredafunctionalprogramminglanguage?a. MLb. Haskellc. Smalltalk

  • 26

    d. Schemee. Lisp

    47. ThemainprogramminglanguageusedinthefieldofNumericalAnalysisis:a. Javab. Haskellc. Fortrand. Assembler

    48. AprogramminglanguageusedheavilyinthefieldofArtificialIntelligenceis:a. Snobolb. Lispc. Fortrand. C++

    49. WhichoftheprogrammingstylesortechniquesisleastwellsupportedbyScheme?a. Functionalprogrammingb. Imperativeprogrammingc. Objectorientedprogrammingd. Recursiveprogramming

    50. Whichofthefollowingisnotapplicationssoftware?a. Wordprocessingb. Spreadsheetc. UNIXd. Desktoppublishing

    51. ConsiderthegrammarS->ABSC/AbcBA->ABBb->bbAb->abAa->aaWhichofthefollowingsentencescanbegeneratedbythisgrammar?

    a. abcb. aabc. abccd. abbc

    52. Themostwidelyusedlogicprogramminglanguageisa. BASICb. COBOLc. PROLOGd. LOGO

    53. (cons’a’(bcd))generatesa. bcdab. abcdc. (bcda)d. (abcd)

    54. (cons(2)(345))generates

  • 27

    a. 2345b. (2345)c. (2)345d. ((2)345)

    55. (append’(bc)’(ef))evaluatestoa. bcefb. (bcef)c. bc(ef)d. ((bc)ef)

    56. (cdr'(abcdef))evaluatestoa. ab. bcdefc. fd. (bcdef)

    57. (car'(abcdef))evaluatestoa. ab. bcdefc. fd. (bcdef)

    58. (list'a'(bc)'(ef))evaluatestoa. abcefb. (a(bc)(ef))c. (abcef)d. ((a)(bc)(ef))

    59. (cadadr'(a(cd)(efg)))returnsa. Ab. Cc. Dd. Ee. G

    60. (caar(list(list'a'b)'c))returnsa. Ab. Bc. Cd. ABC

    61. (cadr(list(list12)(list34)))returnsa. 12b. (12)c. 34d. (34)

    62. Whichofthefollowingistrueofaliases?a. Analiaschangesthenameofsomethingb. Analiasprotectsanexistingvaluefrombeingoverwrittenc. Analiasprovidesanalternativewayofaccessingsomething

  • 28

    d. Analiasallowstypeinferencee. Aliasesshouldbeavoidedifatallpossible

    63. Whathappensinanassignmentsuchas``x:=y''?a. Theaddressofxismodifiedtobetheaddressofyb. Theaddressofyismodifiedtobetheaddressofxc. xandybecomealiasesd. Theobjectboundtoyiscopiedandboundtox,andanypreviousbindingofxto

    anobjectislost64. Whichofthefollowingistrueofl-valuesandr-vlaues?

    a. Anl-valueisalogicalvalue,andanr-valueisarealvalueb. l-valuesarealwaystotheleftofr-valuesc. Anl-valuereferstoavariable’slocationwhileanr-valuetoitscurrentvalued. L-valuesarelocalandr-valuesarerelative

    65. Whichoftheselanguagesdoesnothaveaprimitivedatatypeforacharacterstring:a. CommonLispb. Pascalc. Adad. Java

    66. Whatdistinguishesapurely``functional''programminglanguagefroman``imperative''one?

    a. Therearenovariablesandhencenoassignmentoperationinapurelyfunctionallanguage

    b. Apurelyfunctionallanguagelacksthe``goto''statement,butanimperativelanguagealwayshassuchacommand

    c. Allsubprogramsmustbedeclaredwiththekeywordfunctioninapurelyfunctionallanguage

    d. Thereisnorealdifference,onlyadifferenceintherecommendedcodingstyle67. Prologisastronglytypedlanguage.

    a. Trueb. False

    68. ThescopeofavariableinPrologisasingleclause(i.e.,afactorrule)orasinglequery.a. Trueb. False

    69. OneofPrologstrengthsisitsuseoffuzzylogic.a. Trueb. False

    70. TermsaretoPrologass-expressionsaretoLisp.a. Trueb. False

    71. TheemptylistinPrologisrepresentedbytheatomicsymbolNIL.a. Trueb. False

    72. AvariableinPrologmuststartwitheitheranupper-caseletteroranunderscore(_).a. True

  • 29

    b. False73. AlllocalvariablesmustbedeclaredbeforetheyareusedinProlog.

    a. Trueb. False

    74. APrologvariablecanonlybeassignedtoavalueonce.a. Trueb. False

    75. Inprolog,hasTelephone(mutte).isaa. Factb. Rulec. Queryd. Noneoftheabove

    76. Inprolog,eavesdrops(X,Y):-controls(X,nsa),hasTelephone(Y),usesTelephone(Y).isaa. Factb. Rulec. Queryd. Noneoftheabove

    77. Inprolog,?-k(Y).isaa. Factb. Rulec. Queryd. Noneoftheabove

    78. Inprolog,?-jealous(X,Y).isaa. Factb. Rulec. Queryd. Noneoftheabove

    79. Inprolog,loves(Vincent,mia).isaa. Factb. Rulec. Queryd. Noneoftheabove

    80. Inprolog,jealous(A,B):-loves(A,C),loves(B,C).isaa. Factb. Rulec. Queryd. Noneoftheabove

    81. TheremaybemanysolutionstoaPrologquery.a. Trueb. False

    82. GiventhefollowingsetofPrologclausesfather(X,Y):-parent(X,Y),male(X).parent(sally,bob).parent(jim,bob).

  • 30

    parent(alice,jane),parent(thomas,jane).male(bob).male(jim).male(thomas).female(sally).female(alice).HowmanyatomsarematchedtothevariableXbeforethequeryfather(X,jane)reportsaresult?

    a. 1b. 2c. 3d. 4

    83. GiventhefollowingsetofPrologclausesfather(X,Y):-parent(X,Y),male(X).parent(sally,bob).parent(jim,bob).parent(alice,jane),parent(thomas,jane).male(bob).male(jim).male(thomas).female(sally).female(alice).WhatwillthevariableXbeboundwithwhenthequeryfather(X,jane)reportsaresult?

    a. Bobb. Jimc. Thomasd. jane

    84. Inlogicprogramming,theprogramdeclaresthegoalsofthecomputations,notthemethodforachievingthem

    a. Trueb. False

    85. ForthePROLOGgoal?[[X,Y],Z|R]=[[a,b],[1,2],[c,d]].Whichbindingapply?

    a. X=aY=bZ=[1,2]R=[[c,d]]b. none,becausethegoalfailc. X=aY=bZ=1R=[2,c,d]d. X=aY=bZ=[c,d]R=[c,d]

    86. Incaseofargumentspassedbyvalueswhencallingafunctionsuchasz=addidion(x,y),a. Anymodificationstothevariablesx&yfrominsidethefunctionwillnothave

    anyeffectoutsidethefunction.

  • 31

    b. Thevariablesxandywillbeupdatedwhenanymodificationisdoneinthefunction

    c. Thevariablesxandyarepassedtothefunctionadditiond. Noneofabovearevalid

    87. Incaseofpassbyreference,a. Thevaluesofthosevariablesarepassedtothefunctionsothatitcanmanipulate

    themb. Thelocationofvariableinmemoryispassedtothefunctionsothatitcanuse

    thesamememoryareaforitsprocessingc. Bothaandcd. Noneofaandb

    88. Afunctionmayonlybecalledatoneplaceinaprogram.a. Trueb. False

    89. Informationcanbepassedintoafunctionthroughparameters.a. Tureb. False

    90. InLisp,(+83)returnsa. 8b. 3c. 83d. 11

    91. InLisp,(1234)returnsa. 1b. 2c. 3d. 4e. Error

    92. InScheme,(CAR'((IHATE)(PEANUTBUTTER)(ANDJELLY)))returnsa. IHATEb. (IHATE)c. Id. HATEe. NONEOFTHEABOVE

    93. (CAR(CDR'(SANDWITCH)))returnsa. SANDb. (SAND)c. WITCHd. (WITCH)

    94. Giventhefollowingcode, inta; procedurefoo(intx){ x=x+10; a=a+x;

  • 32

    } procedurefie(){ a=5; foo(a); print(a); } Whatwillbeprintedoutifcallbyvalueisused?

    a. 10b. 15c. 20d. 30e. Noneoftheabove

    95. Giventhefollowingcode, inta; procedurefoo(intx){ x=x+10; a=a+x; } procedurefie(){ a=5; foo(a); print(a); } Whatwillbeprintedoutifcallbyresultisused?

    a. 10b. 15c. 20d. 30e. Noneoftheabove

    96. Giventhefollowingcode, inta; procedurefoo(intx){ x=x+10; a=a+x; } procedurefie(){ a=5; foo(a); print(a); } Whatwillbeprintedoutifcallbyvalue-resultisused?

    a. 10b. 15c. 20

  • 33

    d. 30e. Noneoftheabove

    97. Giventhefollowingcode, inta; procedurefoo(intx){ x=x+10; a=a+x; } procedurefie(){ a=5; foo(a); print(a); } Whatwillbeprintedoutifcallbyreferenceisused?

    a. 10b. 15c. 20d. 30e. Noneoftheabove

    98. Giventhefollowingcode, inta; procedurefoo(intx){ x=x+10; a=a+x; } procedurefie(){ a=5; foo(a); print(a); } Whatwillbeprintedoutifcallbynameisused?

    a. 10b. 15c. 20d. 30e. Noneoftheabove

    99. Whichvariablehasthelongestscope? #includeintb;intmain(){intc;return0;}

  • 34

    inta;a. ab. bc. cd. Bothaandb

    100. Whatistheprogrammingstyleoftheobjectorientedconceptualmodel?a. Invariantrelationshipsb. Algorithmsc. Classesandobjectsd. Goals,oftenexpressedinapredicatecalculus.

  • 35

    CMPS502ComputerOrganization

    1. Adesktopcomputerisdesignedforusebyanindividual,usuallyincorporatingagraphicsdisplay,akeyboard,andamouse.

    A. TrueB. False

    2. Aservercomputerisusedforrunninglargerprogramsformultipleusers,often

    simultaneouslyandtypicallyaccessedonlyviaanetwork.A. TrueB. False

    3. Supercomputerisaclassofcomputerswiththehighestperformanceandcost;theyare

    configuredasserversandtypicallycostmillionsofdollars.A. TrueB. False

    4. Datacenterisaroomorbuildingdesignedtohandlethepower,cooling,andnetworkingneedsoflargenumberofservers.

    A. TrueB. False

    5. Embeddedcomputersarethelargestclassofcomputersandspanthewidestrangeof

    applicationsandperformance.A. TrueB. False

    6. Aprogramthattranslateshigh-levellanguagestatementsintoassemblylanguage

    statementsiscalledA. AssemblerB. CompilerC. InterpreterD. Translator

    7. Aprogramthattranslatessymbolicversionofinstructionsintothebinaryversionis

    calledA. AssemblerB. CompilerC. Interpreter

  • 36

    D. Translator

    8. AbinaryrepresentationofmachineinstructionsiscalledA. AssemblylanguageB. MachinelanguageC. High-levellanguageD. Clanguage

    9. Asymbolicrepresentationofmachinelanguageiscalled

    A. AssemblylanguageB. MachinelanguageC. High-levellanguageD. Clanguage

    10. Acommandthatcomputerhardwareunderstandsandobeysiscalled

    A. LogicB. LanguageC. InstructionD. Translator

    11. Amechanismthroughwhichthecomputerisfedinformation,suchasthekeyboardor

    mouseiscalledA. OutputdeviceB. InputdeviceC. I/OdeviceD. Memory

    12. Amechanismthatconveystheresultofacomputationtoauseroranothercomputeris

    knownasA. OutputdeviceB. InputdeviceC. I/OdeviceD. Networking

    13. Atransistorissimplyanon/offswitchcontrolledbyelectricity.

    A. TrueB. False

  • 37

    14. Anintegratedcircuit(IC)combineddozenstohundredsoftransistorsintoasinglechip.A. TrueB. False

    15. GordonMoore’slawstatesthatnumberoftransistors(i.e.,transistorcapacity)inan

    integratedcircuitdoublesinevery18-24months.A. TrueB. False

    16. Theactivepartofthecomputer,whichcontainsthedatapathandcontrol,andwhich

    addsnumbers,testnumbers,signalsI/OdevicestoactivateisknownasA. CPU(CentralProcessingUnit)B. MemoryhierarchyC. I/OdevicesD. Motherboard

    17. Aplasticboardcontainingpackagesofintegratedcircuitsorchips,includingprocessor,

    cache,memory,andconnectionsforI/OdevicessuchasnetworksanddisksisknownasA. CPUB. MemoryhierarchyC. I/OdevicesD. Motherboard

    18. Thestorageareainwhichprogramsarekeptwhentheyarerunningandthatcontains

    thedataneededbytherunningprogramsiscalledA. CPUB. MotherboardC. IntegratedcircuitsD. Memory

    19. SRAM(staticrandomaccessmemory)isfasterbutlessdense,andhencemore

    expensivethanDRAM(dynamicrandomaccessmemory).A. TrueB. False

    20. Magnetictapeisasequentialaccessmemory.

    A. TureB. False

  • 38

    21. InDRAM(dynamicrandomaccessmemory),memoryaccesstakebasicallythesame

    amountoftimenomatterwhatportionofthememoryisread.A. TrueB. False

    22. DRAM(dynamicrandomaccessmemory)isavolatilestoragethatcontainsdataonlyifit

    isreceivingpower.A. TrueB. False

    23. Magneticdiskisanonvolatilememorybecauseitretainsdataevenintheabsenceof

    powersourceanditisusedtostoreprogramsbetweenruns.A. TrueB. False

    24. Amemorythatisusedtoholdprogramswhiletheyarerunningisknownas

    A. SlowmemoryB. NonvolatilememoryC. MainmemoryD. Secondarymemory

    25. Anonvolatilememory(eg.,magneticdisk)usedtostoreprogramsanddatabetween

    runsisknownasA. SlowmemoryB. NonvolatilememoryC. MainmemoryD. Secondarymemory

    26. Flashmemoryisanonvolatilesemiconductormemory,whichischeaperandslower

    thanDRAM.A. TrueB. False

    27. Flashmemoryismoreexpensiveandfasterthanmagneticdisksmemory.

    A. TrueB. False

  • 39

    28. Therelationshipbetweenperformanceandexecutiontimecanbedefinedas:A. Performance=1/(Executiontime)B. Performance=ExecutiontimeC. Performance=2/(Executiontime)D. Performance=2x(Executiontime)

    29. IftheperformanceofcomputerXisgreaterthantheperformanceofcomputerY,we

    canwrite:A. ExecutiontimeofcomputerX>ExecutiontimeofYB. ExecutiontimeofcomputerX=3x(ExecutiontimeofY)C. ExecutiontimeofcomputerX=1/(ExecutiontimeofY)D. ExecutiontimeofcomputerY>ExecutiontimeofX

    30. IfcomputerArunsaprogramin10secondsandcomputerBrunsthesameprogramin

    15seconds,howmuchfasterisAthanB?A. 1.5B. 2C. 3D. 3.5

    31. TheCPUexecutiontimecanbeexpressedas

    A. CPUexecutiontimeforaprogram=(CPUclockcycleforaprogram)/(Clockcycletime)

    B. CPUexecutiontimeforaprogram=(CPUclockcycleforaprogram)x(Clockrate)C. CPUexecutiontimeforaprogram=(CPUclockcycleforaprogram)x(Clock

    cycletime)D. CPUexecutiontimeforaprogram=(CPUclockcycleforaprogram)x1/(Clock

    cycletime)

    32. TheexecutiontimeoftheprogramaftermakingtheimprovementisgivenbythefollowingsimpleequationknownasAmdahl’slaw:

    A. Executiontimeafterimprovement=(Executiontimeaffectedbyimprovement)/(Amountofimprovement)+Executiontimeunaffected

    B. Executiontimeafterimprovement=(Executiontimeunaffected)/(Amountofimprovement)+Executiontimeaffectedbyimprovement

    C. Executiontimeafterimprovement=(Amountofimprovement)/(Executiontimeunaffected)+Executiontimeaffectedbyimprovement

  • 40

    D. Executiontimeafterimprovement=(Executiontimeunaffected)/(Executiontimeaffectedbyimprovement)+Amountofimprovement

    33. Supposeaprogramrunsin100secondsonacomputer,withmultiplyoperations

    responsiblefor80secondsofthistime.HowmuchdoIhavetoimprovethespeedofmultiplicationifIwantmyprogramtorunfivetimesfaster?(UseAmdahl’slaw).

    A. 50%B. 10%C. ImpossibleD. 5%

    34. Averagenumberofclockcyclesprinstructionforaprogramorprogramfragmentis

    knowsasA. ClockcyclesB. InstructioncountC. Clockcyclesperinstruction(CPI)D. Clockperiod

    35. Thenumberofclockcyclesrequiredforaprogramcanbewrittenas

    A. CPUclockcycles=(Instructionsforaprogram)x(Averageclockcyclesperinstruction)

    B. CPUclockcycles=(Instructionsforaprogram)x(Numberofclockcyclesperinstruction)

    C. CPUclockcycles=(Instructionsforaprogram)x(Totalclockcycles)D. CPUclockcycles=(Instructionsforaprogram)x(Totalclockcyclesper

    instruction)

    36. TheclassicCPUperformanceequationiswrittenasA. Instructioncount=(CPUtime)x(CPI)x(Clockcycletime)B. Clockcycletime=(Instructioncount)x(CPI)x(CPUtime)C. CPI=(Instructioncount)x(CPUtime)x(Clockcycletime)D. CPUtime=(Instructioncount)x(CPI)x(Clockcycletime)

    37. TheclassicCPUperformanceequationiswrittenas

    A. CPUtime=(Instructioncount)x(CPI)/(Clockrate)B. CPUtime=(Instructioncount)x(Clockrate)/(CPI)C. CPUtime=(CPI)x(Clockrate)/(Instructioncount)D. CPUtime=(CPI)/(Clockrate)x(Instructioncount)

  • 41

    38. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) Howmanyinstructionscodesequence1executes?

    A. 2B. 3C. 4D. 5

    39. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) Howmanyinstructionscodesequence2executes?

    A. 3B. 4C. 5D. 6

    40. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) Whichcodesequenceexecutesmoreinstructions?

    A. Codesequence1B. Codesequence2C. Bothcodesequencesexecutesamenumberofinstructions

  • 42

    41. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) Howmanyclockcyclesarerequiredforcodesequence1?

    A. 6B. 9C. 10D. 12

    42. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) Howmanyclockcyclesarerequiredforcodesequence2?

    A. 6B. 9C. 10D. 12

    43. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) Whichcodesequenceneedsmoreclockcycles?

    A. Codesequence2B. Codesequence1C. Bothcodesequencesneedsameamountofclockcycles

  • 43

    44. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) Whichcodesequenceisfaster?

    A. Codesequence1B. Codesequence2

    45. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) WhatistheCPIforcodesequence1?

    A. 1B. 1.5C. 2.0D. 2.5

    46. Acompilerdesigneristryingtodecidebetweentwocodesequencesforaparticular

    computer.Thehardwaredesignershavesuppliedthefollowingfacts:CPIforR-typeinstructionis1,CPIforI-typeinstructionis2,andCPIforJ-typeinstructionis3.Thetwosequenceshavethefollowinginstructioncounts:

    Codesequence1:R-type(2),I-type(1),J-type(2) Codesequence2:R-type(4),I-type(1),J-type(1) WhatistheCPIforcodesequence2?

    A. 1B. 1.5C. 2.0D. 2.5

  • 44

    47. TheMIPSprocessorparadigmwascreatedatStanfordUniversitybyA. J.L.HennessyB. D.PattersonC. G.MooreD. A.Tour

    48. MIPSstandsfor

    A. MIllionsofInstructionProcessingperSecondB. MicroprocessorwithoutInterlockedPipelineStagesC. MicroprocessorInstructionProcessingStyleD. MillionsInstructionsProgramSet

    49. MIPSisa

    A. RISCprocessorB. CISCprocessor

    50. MIPSR2000hashowmanytemporaryregisters?

    A. 10B. 30C. 32D. 4

    51. MIPSR2000registersare______inlength.

    A. 32bitsB. 16bitsC. 64bitsD. 8bits

    52. Registernumberzeroisareservedregister.

    A. TrueB. False

    53. Ifyouwanttoexittheprogram,v0registermustbeloadedwith

    A. 10B. 7C. 5D. 0

  • 45

    54. Ifyouwanttoreadanintegervaluefromconsole,v0registermustbeloadedwithA. 10B. 7C. 5D. 0

    55. Ifyouwanttoprintastring,v0registermustbeloadedwith4A. TrueB. False

    56. Whatisthemeaningoftheinstructionbne$s1,$s2,25?A. If($s2>=25)$s1=1;else$s1=0B. If($s1>=$s2)$s1=1;else$s1=0C. If($s2>=$s3)$s1=1;else$s1=0D. If($s1!=$s2)gotoPC+4+100

    57. Whatisthemeaningoftheinstructionslt$s1,$s2,$s3?

    A. If($s2>=$s3)$s1=1;else$s1=0B. If($s2=20)$s1=1;else$s1=0B. If($s2=20)$s1=1;else$s1=0B. If($s2>10B. $s2=$s1>>10C. $s1=$s2

  • 46

    61. Whatisthemeaningoftheinstructionsll$s1,$s2,10?A. $s1=$s210D. $s2=$s1>>10

    62. Whatisthemeaningoftheinstructionsw$s1,20($s2)?

    A. $s2=Memory[$s1+20]B. $s1=Memory[$s2+20]C. Memory[$s1+20]=$s2D. Memory[$s2+20]=$s1

    63. Whatisthemeaningoftheinstructionlw$s1,20($s2)?

    A. $s2=Memory[$s1+20]B. $s1=Memory[$s2+20]C. Memory[$s1+20]=$s2D. Memory[$s2+20]=$s1

    64. Whatisthemeaningoftheinstructionjal2500?

    A. $ra=PC+4;goto2500x1=2500B. $ra=PC+4;goto2500x2=5000C. $ra=PC+4;goto2500x3=7500D. $ra=PC+4;goto2500x4=10000

    65. Assumethatthevariablesfandgareassignedtoregisters$s0and$s1respectively.

    AssumethatthebaseaddressofarrayAisinregister$s6.WhatistheCcodecorrespondingtothefollowingMIPScode?

    lw$s0,16($s6) sub$s0,$0,$s0 sub$s0,$s0,$s1

    A. f=-g-A[4]B. g=f-A[4]C. f=-g+A[16]D. f=-g-A[16]

  • 47

    66. Assumethatthevariablesiandjareassignedtoregisters$s3and$s4respectively.AssumethatthebaseaddressofarraysAandBareinregisters$s6and$s7,respectively.WhatistheMIPScodecorrespondingtothefollowingCcode? B[8]=A[4]+i-j

    A. sub$t0,$s3,$s4

    lw$t1,16($s6)add$t0,$t0,$t1sw$t0,32($s7)

    B. sub$t0,$s3,$s4 lw$t1,16($s6)

    add$t0,$t0,$t1sw$t1,32($s7)

    C. sub$t1,$s3,$s4 lw$t1,16($s6)

    add$t0,$t0,$t1sw$t0,32($s7)

    D. sub$t0,$s3,$s4 lw$t1,16($s7)

    add$t0,$t0,$t1sw$t0,32($s6)

    67. Assumethatthevariablesf,g,h,iandjareassignedtoregisters$s0,$s1,$s2,$s3and

    $s4respectively.AssumethatthebaseaddressofarraysAandBareinregisters$s6and$s7,respectively.WhatistheCcodecorrespondingtothefollowingMIPScode??

    slli$s2,$s4,1add$s0,$s2,$s3add$s0,$s0,$s1j

    A. f=2j+i+gB. g=2i+f+jC. i=4f+j+hD. f=4j+i+g

    68. ConsiderthefollowingMIPSassemblylanguagecode:

    .datamsg:.asciiz“HelloWorld\n”

  • 48

    .text .globlmain: li$v0,4 li$a0,msg syscall li$v0,10 syscallWhatwillbetheoutputoftheaboveprogram?

    A. ThereisanerrorintheprogramandnooutputB. HelloWordC. “HelloWord”D. Nothing

    69. ConsiderthefollowingMIPSassemblylanguagecode:

    .datamsg:.asciiz“HelloWorld\n”msg1.asciiz“HelloClass\n”

    .text .globlmain: li$v0,4 li$a0,msg li$a0,msg1 syscall li$v0,10 syscallWhatwillbetheoutputoftheaboveprogram?

    A. ThereisanerrorintheprogramandnooutputB. HelloWordC. “HelloWord”D. HelloClass

  • 49

    70. Apipelinehazardsoccurswhenthepipeline,orsomeportionofthepipeline,muststallbecauseconditionsdonotpermitcontinuedexecution.

    A. TrueB. False

    71. A_____________hazardoccurswhentwo(ormore)instructionsthatarealreadyinthe

    pipelineneedthesameresource.A. ResourceB. DataC. Control

    72. A_____________hazardoccurswhenthereisaconflictintheaccessofanoperandlocation.

    A. ResourceB. DataC. Control

    73. A___________hazardoccurswhenthepipelinemakesthewrongdecisiononabranch

    predictionandthereforebringsinstructionintothepipelinethatmustsubsequentlybediscarded.

    A. ResourceB. DataC. Control

    74. Inwhichofthefollowingdependency,aninstructionmodifiesaregisterormemory

    locationandasucceedinginstructionreadsthedatainthatmemoryorregisterlocation?

    A. ReadafterwriteB. WriteafterreadC. WriteafterwriteD. Readafterread

    75. Inwhichofthefollowingdependency,aninstructionreadsaregisterormemory

    locationandasucceedinginstructionwritestothelocation.A. ReadafterwriteB. WriteafterreadC. WriteafterwriteD. Readafterread

  • 50

    76. Inwhichofthefollowingdependency,twoinstructionsbothwritetothesamelocation.A. ReadafterwriteB. WriteafterreadC. WriteafterwriteD. Readafterread

    77. Insuperscalarprocessor,out-of-orderissuepolicyisdonewithabufferreferredtoas

    a(n)A. InstructionwindowB. ForwardmemoryC. InstructionlabelD. Forwardmemory

    78. Insuperscalarprocessor,theterm“instructionissue”referstotheprocessofinitiating

    instructionexecutionintheprocessor’s________________unit.A. FunctionalB. DecodingC. WritebackD. Fetch

    79. Insuperscalarprocessor,theterm“instructionissuepolicy”referstotheprotocolused

    toissueinstruction.A. TrueB. False

    80. Insuperscalarprocessor,out-of-ordercompletionisusedinscalarRISCprocessorsto

    improvetheperformanceofinstructionsthatrequiremultiplecycles.A. TrueB. False

    81. Thesimplestinstructionissueandcompletionpolicyis

    A. In-orderissueandin-ordercompletionB. In-orderissueandout-of-ordercompletionC. Out-of-orderissueandout-of-ordercompletionD. Out-of-orderissueandin-ordercompletion

    82. OneofthecharacteristicsofReducedInstructionSetComputers(RISC)isoneinstruction

    percycle.

  • 51

    A. FalseB. True

    83. OneofthecharacteristicsofReducedInstructionSetComputers(RISC)isregisterto

    registeroperations.A. TrueB. False

    84. ReducedInstructionSetComputers(RISC)architecturehasmoreinstructionscompared

    toComplexInstructionSetComputer(CISC)architecture.A. True B. False

    85. Delayedbranch,awayofincreasingtheefficiencyofthepipeline,makesuseofabranch

    thatdoesnottakeeffectuntilafterexecutionofthefollowinginstruction.A. TrueB. False

    86. Instructionlevelparallelism(ILP)referstothedegreetowhich,onaverage,the

    instructionsofaprogramcanbeexecutedinparallel.A. TrueB. False

    87. Inregisterrenaming,registersareallocateddynamicallybytheprocessorhardware,and

    theyareassociatedwiththevaluesneededbyinstructionsatvariouspointsintime.A. TrueB. False

    88. Considerthefollowingcodesequencewithsuperscalarprocessor:

    I1:R3:=R3opR5I2:R4:=R3+1I3:R3:=R5+1I4:R7:=R3opR4WhattypesofdependencyI2andI3have?

    A. TruedatadependencyB. AntidependencyC. ResourceConflict

  • 52

    D. Outputdependency

    89. Considerthefollowingcodesequencewithsuperscalarprocessor:I1:R3:=R3opR5I2:R4:=R3+1I3:R3:=R5+1I4:R7:=R3opR4WhattypesofdependencyI1andI3have?

    A. TruedatadependencyB. AntidependencyC. ResourceConflictD. Outputdependency

    90. Considerthefollowingcodesequencewithsuperscalarprocessor:

    I1:R3:=R3opR5I2:R4:=R3+1I3:R3:=R5+1I4:R7:=R3opR4Whichofthefollowingmethodwillsolvethedependenciesintheabovecodesegment?

    A. SpeculativeloadingB. PredictionC. ForwardingD. Registerrenaming

    91. ConsiderthefollowingMIPSassemblylanguagecodesequence:

    I1:add$s3,$s4,$s215I2:sub$s5,$s3,$s1I3:lw$s6,200($s3)I4:add$s7,$s3,$s6WhattypesofdependencyI1andI2have?

    A. TruedatadependencyB. AntidependencyC. ResourceConflictD. Outputdependency

  • 53

    92. ConsiderthefollowingMIPSassemblylanguagecodesequence:I1:add$s3,$s4,$s2I2:sub$s5,$s3,$s1I3:lw$s6,200($s3)I4:add$s7,$s3,$s6WhattypesofdependencyI2andI3have?

    A. TruedatadependencyB. ResourceConflictC. OutputdependencyD. NoDependency

    93. ConsiderthefollowingMIPSassemblylanguagecodesequence:

    I1:add$s3,$s4,$s2I2:sub$s5,$s3,$s1I3:lw$s6,200($s3)I4:add$s7,$s3,$s6WhattypesofdependencyI3andI4have?

    A. TruedatadependencyB. AntidependencyC. ResourceConflictD. Outputdependency

    94. ConsiderthefollowingMIPSassemblylanguagecodesequence:

    I1:add$s3,$s4,$s2I2:sub$s5,$s3,$s1I3:lw$s6,200($s3)I4:add$s7,$s3,$s6Whichofthefollowingdependencywillcauseastall?

    A. DependencybetweenI1&I2B. DependencybetweenI2&I3C. DependencybetweenI3&I4D. DependencybetweenI1&I3

    95. ConsiderthefollowingMIPSassemblylanguagecodesequence:

    I1:add$s3,$s4,$s2

  • 54

    I2:sub$s5,$s3,$s1I3:lw$s6,200($s3)I4:add$s7,$s3,$s6Whichofthefollowingdependencycanbesolvebyforwardingorbypassing?

    A. DependencybetweenI1&I2B. DependencybetweenI2&I3C. DependencybetweenI3&I4D. DependencybetweenI1&I4

    96. WhatarethefourexecutionunitsthatIA-64processorshave?

    A. A-unit,B-unit,C-unit,D-unitB. I-unit,M-unit,B-unit,F-unitC. I-unit,C-unit,B-unit,F-unitD. I-unit,D-unit,B-unit,F-unit

    97. WhatistheinstructionlengthofIA-64processors?

    A. 32-bitB. 64-bitC. 128-bitD. 256-bit

    98. WhatarethekeymechanismsofIA-64architecture?

    A. Prediction,controlspeculation,dataspeculation,andsoftwarepipeliningB. Prediction,controlspeculation,dataspeculation,andhardwarepipeliningC. Prediction,addressspeculation,dataspeculation,andsoftwarepipeliningD. Predication,controlspeculation,dataspeculation,andsoftwarepipelining

    99. _____________isatechniquesusedtooptimizeloopsinamannerthatparallels

    hardwarepipelining.A. SoftwarepipeliningB. HardwarepipeliningC. ControlspeculationD. Dataspeculation

    100. With_____________,allpossiblebranchpathsareexecuted,thecorrectoneis

    keptandallotherarethrowaway.A. Softwarepipelining

  • 55

    B. BranchpredicationC. BranchpredictionD. Controlspeculation

  • 56

    CMPS512TheoryofComputing

    1. Forthefollowingstatements:(1).IfSisafiniteset,|2s|=2|S|;(2).IfS1andS2arefinitesetswith|S1|=nand|S2|=m,then|S1US2|≤n+m;whichofthefollowingisright:(A).(1)isright.(B).(1)and(2)areright. (C).(2)isright.(D).Noneof(1)and(2)isright.

    2. Whichofthefollowingstatementscanberight:(1).AgrammarGcanbeaquadruple(V,T,S,P)andtheproductionrulesaretheheartofagrammar.(2).Anautomatoncanhavethreecomponents:inputfile,controlunit,andstorage.(A).Only(1)isright. (B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    3. IfS={2,5,6,8}andT={2,4,6,8},then|SUT|+|S∩T|=(A).12.(B).9.(C).8.(D).7.

    4. Whichofthefollowingstatementscanberight:(1).S1=S2isequivalenttoS1US2=S1∩S2;(2).IfS1andS2arefinitesets,then|S1×S2|=|S1||S2|.(A).(1)isright.(B).Both(1)and(2)areright.(C).(2)isright.(D).Noneof(1)and(2)isright.

    5. Whichofthefollowingstatementscanberight:(1).Ifx=O(n4),y=O(n2),thenx/y=O(n2).(2).Ifx=Θ(n4),y=Θ(n2),thenx/y=Θ(n2).(A).Only(1)isright. (B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    6. Whichofthefollowingstatementscanberight:Iff(n)=O(n2),g(n)=O(n3),then(1).f(n)+g(n)=O(n3).(2).f(n)g(n)=O(n5).(A).Only(1)isright. (B).Only(2)isright.

  • 57

    (C).Both(1)and(2)areright.(D).(1)isrightand(2)iswrong.

    7. Whichofthefollowingstatementsmaybetrue:(1).(wR)R=wforallw∈Σ*.(2).IfL={ab,aa,baa},thenthestringaaaabaaaaandbaaaaabaaareinL4.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    8. Whichofthefollowingstatementsmaybetrue:(1).(L*)*=L*foralllanguagesL.(2).(LR)*=L*foralllanguagesL.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    9. WhichofthefollowinglanguageisgeneratedbythegrammarwithproductionsSàaaA,AàbS,andSàλ:(A).L={(aa)nb:n≥0}.(B).L={aa(b)n:n≥0}.(C).L={(aab)n:n≥0}.(D).L={(a)nb:n>0}.

    10. ThegrammarSàaaSbb|aSb|ab|λisequivalenttothefollowinggrammar:(A).SàaaSb|ab|λ.(B).SàaSbb|ab|λ.(C).SàaSb|ab|λ.(D).SàaSb|aabb|λ

    11. Whichofthefollowingstatementsmayberight:(1).AdeterministicfiniteautomatoncanhaveonlyquadrupleM={Q,δ,q0,F};(2).LanguageL={an:n≥3}isregular.(A).Only(1)isright.(B).Both(1)and(2)areright.(C).(1)iswrongand(2)isright.(D).Noneoftheaboveisright.

    12. Whichofthefollowingstatementsmayberight:(1).ThelanguageL={an:n≥0,n≠3}isregular.(2).LanguageL={an:niseitheramultipleof3oramultipleof5}isregular.(A).Only(1)isright.

  • 58

    (B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    13. Whichofthefollowingstatementsmayberight:(1).ThelanguageL={an:nisamultipleof3butnotamultipleof5}isregular.(2).ThesetofallrealnumberinCisnotaregularlanguage.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    14. Whichofthefollowingstatementsmayberight:(1).ThelanguageL={an:nisamultipleof3butnotamultipleof5}isregular.(2).ThesetofallrealnumberinCisnotaregularlanguage.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    15. Whichofthefollowingstatementsmayberight:(1).IflanguageLisregularthenL–{λ}isalsoregular.(2).IflanguageLisregularthenforalla∈Σ,LU{aa}isalsoregular.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    16. Forthefollowingautomaton,whichofthefollowingstatementsmaybetrue:(1).ItisaDFA.(2).ItisaNFAthatacceptsallintegernumbersinC.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    17. Whichofthestrings00,01001,10010,000,and0000areacceptedbythefollowingNFA?(A).00and01001.(B).01001and000.(C).10010and0000.(D).000and0000.

    1 2.2

    1. Construct an nfa that accepts all integer numbers in C.

    Solution: Integer numbers in C have the form .A solution is

    2. Prove in detail the claim made in the previous section that if in atransition graph there is a walk labeled w, there must be some walklabeled w of length no more than ⇤+ (1 + ⇤) |w|.

    Solution: Suppose we have a walk labeled w = a1a2...an in a graphwith ⇤ �-transitions.Then any walk labeled w that includes �- edgescan be described by the form

    u = �k1a1�k2 ...�knan�

    kn+1 ,

    where �ki denotes successive traversal ki �-edges and ai denotes thetraversal of an edge labeled ai . Denoting the length of u by |u| wehave

    |u| = (k1 + k2 + ...+ kn+1) + (|a1|...+ |an|)= (n+ 1)⇤+ n

    = ⇤+ (1 + ⇤)|w|.

    3. ** Find a dfa that accepts the language defined by the nfa in Figure2.8.

    1

    1 2.2

    1. Construct an nfa that accepts all integer numbers in C.

    Solution: Integer numbers in C have the form .A solution is

    2. Prove in detail the claim made in the previous section that if in atransition graph there is a walk labeled w, there must be some walklabeled w of length no more than ⇤+ (1 + ⇤) |w|.

    Solution: Suppose we have a walk labeled w = a1a2...an in a graphwith ⇤ �-transitions.Then any walk labeled w that includes �- edgescan be described by the form

    u = �k1a1�k2 ...�knan�

    kn+1 ,

    where �ki denotes successive traversal ki �-edges and ai denotes thetraversal of an edge labeled ai . Denoting the length of u by |u| wehave

    |u| = (k1 + k2 + ...+ kn+1) + (|a1|...+ |an|)= (n+ 1)⇤+ n

    = ⇤+ (1 + ⇤)|w|.

    3. ** Find a dfa that accepts the language defined by the nfa in Figure2.8.

    1

    13. ** Which of the strings 00, 01001, 10010, 000, 0000 are accepted bythe following nfa?

    Solution: 01001 and 000 are the only two strings accepted.

    14. What is the complement of the language accepted by the nfa in Figure2.10?

    Solution: It is not di�cult to see the language is L = {an : n � 1}.Therefore L̄ = {�}. The automaton below with single initial and finalstate is a solution.

    15. ** Let L be the language accepted by the nfa in Figure 2.8. Find annfa that accepts L [ {a5}.

    Solution: Add two states after the nfa accepts a3 with both new edgeslabeled a.

    16. Find an nfa for L⇤, where L is the language in Exercise 15.

    5

  • 59

    18. Whichofthefollowingstatementsmayberight:(1).IflanguageLisregularthenLRisalsoregular.(2).ANFAcanbeconvertedtoaDFA.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    19. Whichofthefollowingstatementsmayberight:(1).Theautomatongeneratedbyprocedurereduceisdeterministic.(2).IfLisanonemptylanguagesuchthatanywinLhaslengthatleastn,thenanyDFAacceptingLmusthaveatleastn+1states.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    20. Whichofthefollowingstatementsmayberight:(1).AregularlanguagecanbeacceptedbyaTuringmachine.(2).Aregularlanguagecanbeacceptedbyapushdownautomaton.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    21. Aregularexpressionfortheset{anbm:n≥3,misodd}canbe:(A).aaab.(B).aaabbb.(C).aaaa*(bb)*b.(D).Noneoftheaboveisright.

    22. Aregularexpressionfortheset{anbm:(n+m)isodd}canbe:(A).aaab*.(B).(aa)*(a+b)(bb)*.(C).a(aa)*bbb.(D).Noneoftheaboveisright.

    23. AregularexpressionforthelanguageL={anbm:n≥3,m≤4}canbe:(A).aaaa*(λ+b+bb+bbb+bbbb).(B).aaabbb.(C).aaab.(D).Noneoftheaboveisright.

  • 60

    24. Whichofthefollowingstatementsmayberight:(1).λisaregularexpressiondenoting{λ}.(2).TheLRofL((ab+b)*b(a+ab)*)is(a+ba)*b(b+ba)*.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    25. AregularexpressionforL={abnw:n≥4,w∈{a,b}+}canbe:(A).abbbb.(B).abbbbb*.(C).abbbbb*(a+b)(a+b)*.(D).abbbbb*(a+b).

    26. AregularexpressionforL={w∈{0,1}*:whasexactlyonepairofconsecutivezeros}canbe:(A).(1+01)*00(1+10)*.(B).(1+01)*00.(C).00.(D).(1+10)*00.

    27. Aregularexpressionforthelanguagewithallstringsnotendingin10on{0,1}canbe:(A).00+01+11+0+1.(B).00+01+11+0+1.(C).(0+1)*(00+01+11)+λ+0+1.(D).00+01+11+0+1+λ.

    28. AregularexpressionforthelanguageL={w:na(w)mod3=0}on{a,b}canbe:(A).ab*ab*ab*.(B).(ab*ab*ab*)*.(C).(b*ab*ab*ab*)*.(D).Noneoftheaboveisright.

    29. ThelanguagewhichaccepttheNFAbelowcanbewrittenas:(A).L((aab)ab).(B).L((aab)*ab).(C).L((aab)+ab).(D).Noneoftheaboveisright.

    30. TheregulargrammarthatgeneratesthelanguageL(aa*(ab+a)*)canbewrittenas:

    1 3.2

    1. Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L (a⇤a+ ab).

    Solution:

    2. ** Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L ((aab)⇤ab).

    Solution:

    3. Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L (ab⇤aa+ bba⇤ab).

    1

  • 61

    (A).SàaA,AàaA|B|λ.(B).SàaA,AàaAb|B|λ.(C).SàaA,AàaA|B,BàabB|aB|λ.(D).Noneoftheaboveisright.

    31. IfL1=L(ab*aa),L2=L(a*bba*),aregularexpressionof(L1UL2)*L2is:(A).ab*aa*bba*(a*bba*).(B).ab*aa*bba*+a*bba*.(C).((ab*aa)+(a*bba*))*(a*bba*).(D).Noneoftheaboveisright.

    32. Whichofthefollowingstatementsmayberight:(1).Ifalanguagefamilyisclosedunderunionandcomplementation,itmustbeclosedunderintersection.(2).WecanconstructaNFAthatacceptL(ab*a*)∩L(a*b*a).(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    33. Whichofthefollowingstatementsmayberight:(1).Thefamilyofregularlanguageisclosedunderfiniteunionandintersection.(2).SomeNFAscannotbeconvertedtoDFA.(A).Only(1)isright.(B).(1)iswrongand(2)isright.(C).(1)isrightand(2)iswrong.(D).Noneoftheaboveisright.

    34. Whichofthefollowingaretrueforallregularlanguagesandallhomomorphism:(1).h(L1UL2)=h(L1)Uh(L2).(2).h(L1∩L2)=h(L1)∩h(L2).(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Noneoftheaboveisright.

    35. IfL1=L(a*baa*)andL2=L(aba*),thenL1/L2equalsto(A).a*b.(B).ba*.(C).a*.(D).Noneoftheabove.

    1 3.2

    1. Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L (a⇤a+ ab).

    Solution:

    2. ** Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L ((aab)⇤ab).

    Solution:

    3. Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L (ab⇤aa+ bba⇤ab).

    1

    1 3.2

    1. Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L (a⇤a+ ab).

    Solution:

    2. ** Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L ((aab)⇤ab).

    Solution:

    3. Use the construction in Theorem 3.1 to find an nfa that accepts thelanguage L (ab⇤aa+ bba⇤ab).

    1

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    36. Whichofthefollowingaretrue:(1).ForalllanguagesL1andL2,L1=L1L2/L2.(2).IfL1UL2isregularandL1isfinite,thenL2isregular.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Noneoftheaboveisright.

    37. Whichofthefollowingaretrue:(1).IfLisaregularlanguages,thenL1={uv:u∈L,|v|=2}isalsoregular.(2).IfLisaregularlanguages,thenL1={uv:u∈L,v∈LR}isalsoregular.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    38. Whichofthefollowingaretrue:(1).Thereexistsanalgorithmtodeterminewhetherornotw∈L1–L2,foranygivenwandanyregularlanguageL1andL2.(2).ThereexistsanalgorithmfordeterminingifL1isapropersubsetofL2,foranyregularlanguageL1andL2.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    39. Whichofthefollowingaretrue:(1).Thereexistsanalgorithmfordeterminingwhetherornotλ∈LforanyregularlanguageL.(2).NoalgorithmexistsfordeterminingifL∈Σ*foranyregularlanguageL.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    40. Whichofthefollowingaretrue:(1).Thereexistsanalgorithmfordeterminingwhetherornot|L|≥5foreveryregularlanguageL.(2).ThereexistsanalgorithmfordeterminingifaregularlanguageLcontainsafinitenumberofeven-lengthstrings.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

  • 63

    41. Whichofthefollowingaretrue:(1).ThelanguageL={anbkcn:n≥0,k≥0}isnotregular.(2).ThelanguageL={anbkcn:n≥0,k≥n}isnotregular.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    42. Whichofthefollowingaretrue:(1).ThelanguageL={anbn:n≥1}U{anbm:n≥1,m≥1}isregular.(2).ThelanguageL={anbn:n≥1}U{anbn+2:n≥1}isregular.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    43. Whichofthefollowingaretrue:(1).ThelanguageL={anbn:n≥0}U{anbn+1:n≥0}U{anbn+2:n≥0}isnotregular.(2).ThelanguageL={anbn+k:n≥0,k≥1}U{an+kbn:n≥0,k≥3}isnotregular.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    44. Whichofthefollowingaretrue:(1).ThelanguageL={wwRv:v,w∈{a,b}+}isnotregular.(2).ThelanguageL={w1cw2:w1,w2∈{a,b}*,w1≠w2}isregular.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    45. Whichofthefollowingaretrue:(1).Thecontext-freegrammarforlanguageL=anbn,nisodd,isSàaaSbb|λ.(2).Thecontext-freegrammarforlanguageL=anbn,nisamultipleof3,isSàaaaSbbb|λ.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    46. Whichofthefollowingaretrue:(1).Thecontext-freegrammarforlanguageL={anbn,n≤m+3,n≥0,m≥0}is:odd,isSàaSb|A|B,Aàλ|a|aa|aaa,BàbB|b.(2).The

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    context-freegrammarforlanguageL={anbm:2n≤m≤3n}isamultipleof3,isSàaaaSb|aaaSb|λ.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    47. Whichofthefollowingaretrue:(1).Acontext-freegrammarforlanguageL={anwwRbn,:w∈Σ*,n≥1}forΣ={a,b}canbeSàaSb|S1,S1àaS1a|bS1b|λ.(2).IflanguageL={anbn:n≥0},thenL2isnotcontext-free.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    48. Whichofthefollowingaretrue:(1).ThelanguageL={uvwvR:u,v,w∈{a,b}+,|u|=|w|=2}iscontext-free.(2).ThelanguageL={w1cw2:w1,w2∈{a,b}+,w1≠w2R}withΣ={a,b,c}iscontext-free.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    49. Whichofthefollowingaretrue:(1).ThegrammarSàAB|aaaB,Aàa|Aa,andBàbisambiguous.(2).Aregularlanguagecanbeinherentlyambiguous.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    50. Whichofthefollowingaretrue:(1).It’spossibleforaregulargrammartobeambiguous.(2).ThegrammarSàaSbS|bSaS|λisambiguous.(A).Only(1)istrue.(B).(1)isfalseand(2)istrue.(C).(1)istrueand(2)isfalse.(D).Both(1)and(2)aretrue.

    51. SimplifythegrammarSàaS|AB|λ,AàbA,andBàAA,weget:(1).SàaS|λ.(2).L(a*).(3).SàaS|bb|λ.(A).Only(1)isright.

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    (B).Only(2)and(3)areright.(C).Only(1)and(2)areright.(D).Allof(1),(2),and(3)areright.

    52. Eliminateallλ-productionsfromSàaSSSandSàbb|λ,weget:(1).Sàa|bb|bb|bb|aandSàbb.(2).Sàa|SSS|aSS|aS|aandSàbb.(A).Only(1)isright. (B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    53. Eliminateallλ-productionsfromSàAaB|aaB,Aàλ,BàbbA|λ,weget:(1).SàaB|aaB|a|aaandSàbb.(2).Sàabb|aabbandBàbb.(A).Only(1)isright. (B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    54. EliminatethevariableBfromthegrammarSàaSB|bBandSàbb|λ,weget:(1).SàaSaA|aSb|baA|bb.(2).SàaSaA|b|baA|b.(A).Only(1)isright. (B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    55. WhichofthefollowingchoiceisrightforthegrammarSàabAB|ba,Aàaaa,BàaA|bbandSàabAaA|abAbb|ba,Aàaaa.(A).Theyarenotequivalent.(B).Theyareequivalent.(C).Thefirstiscontextfreeandthesecondiscontextsensitive.(D).Thefirstiscontextsensitiveandthesecondiscontextfree.

    56. Whichofthefollowingstatementsmaybetrue:(1).BothChomskynormalformandGreibachnormalformcanbeusedtorepresentacontextfreegrammar.(2).EverycontextfreegrammarwithoutλcanbeconvertedintoGreibachnormalform.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.

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    (D).Noneoftheaboveisright.

    57. TheChomskynormalformofthegrammarSàaSS|a|bis:(1).SàVaVs|a|b,VsàSS,Vaàa.(2).SàVaVs|a|b,VsàSS|b,Vaàa.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    58. TheGreibachnormalformofthegrammarSàaSb|bSa|a|b|abis:(1).SàaSb|VbSVa|a|b|VaVb,Vaàa,Vbàb.(2).SàaSVb|bSVa|a|b|aVb,Vaàa,Vbàb.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    59. TheGreibachnormalformofthegrammarSàaSb|ab|bbis:(1).SàaSVb|aVb|bVb,Vbàb.(2).SàaSVb|aVb|VbVb,Vbàb.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    60. Whichofthefollowingstatementscanbetrue:(1).Everylineargrammarcanbeconvertedtoaregulargrammar.(2).TheChomskynormalformofacontextfreelanguagewithoutλcanbeconvertedintoaGreibachform.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Neither(1)nor(2)isright.

    61. Forpushdownautomata,whichofthefollowingstatementsarecorrect:(1).Pushdownautomatadescribecontextfreelanguage,sotheyareequivalenttocontextfreegrammar.(2).Pushdownautomataincludeeveryelementoffiniteautomata.(3).Pushdownautomatafollowleftmostderivationorder,thustheyneedtouseastackastheirunboundedstorage.(A).Only(1)isright.(B).Only(2)and(3)areright.(C).Only(1)and(2)areright.(D).Allof(1),(2),and(3)areright.

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    62. Whichofthefollowingstatementsareright:(1).Pushdownautomatahaveseven

    elements:M=(Q,Σ,Г,δ,q0,Z0,F),theyarepatternmodelofcontextfreelanguafeForpushdownautomata,whichofthefollowingstatementsarecorrect:(1).Pushdownautomatadescribecontextfreelanguage,sotheyareequivalenttocontextfreegrammar.(2).Pushdownautomataincludeeveryelementoffiniteautomata.(3).Pushdownautomatafollowleftmostderivationorder,thustheyneedtouseastackastheirunboundedstorage.(A).Only(1)isright.(B).Only(2)and(3)areright.(C).Only(1)and(2)areright.(D).Allof(1),(2),and(3)areright.

    63. Whichofthefollowingstatementsareright:(1).Thestatesofpushdownautomatarepresentthegrammarvariablesofderivativesentencesincorrespondingregularlanguage.(2).Inapushdownautomatastack,theleftmostvariableisputontopofthestackwhiletherightmostoneonbottom.(3).Oncethestackisempty,thesentenceisgenerated.(A).Only(1)isright.(B).Only(2)and(3)areright.(C).Only(1)and(2)areright.(D).Allof(1),(2),and(3)areright.

    64. Pushdownautomatahavefollowingbasiccomponents:(1).Inputfiletape.(2).Stackstorage.(3).Controlunit.(4).Readandwritetape.(A).(1)and(2).(B).(3)and(4).(C).(1),(2),and(3).(D).(2),(3),and(4).

    65. ToconstructapushdownautomatonthatacceptlanguageL={w2wT|w∈{0,1}*},whichofthefollowingdesigncanberight:(1).TwostepsM1=({q0},{0,1,2},{S,A,B},δ1,q0,S,Φ)andM2=({q0,q1},{0,1,2},{S,A,B,Z0},δ2,q0,Z0,{q1}),whereZ0isthetopstacksymbol,andthenconstructthemachinebystandardmethod.(2).M=({q0,q1,q2,qf,qt},{0,1,2},{A,B,Z0},δ,q0,Z0,{qf}),whereqtisthetrapstate.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

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    66. Toconstructapushdownautomatonthatacceptthelanguagedefinedbythegrammar

    SàaSSSab|λ,wecandothefollowingimplementation:(1).Convertthegrammarintoaregulargrammar.(2).ConvertthegrammarintoGreibachform.SàaSSSA|λ,AàaB,andBàb.(3).Followthestandardconstructionmethodtobuildtheautomaton.Whichofthefollowingchoicesareright:(A).(1)and(2).(B).(2)and(3).(C).(1)and(3).(D).(1),(2),and(3).

    67. Whichofthefollowingstatementonpushdownautomataandcontextfreelanguage/grammarareright:(1).Pushdownautomataisequivalenttocontextfreegrammar.(2).Contextfreelanguagecanbeacceptedbypushdownautomatawhichcanuseemptystacktoacceptlanguage.(3).Thepushdownautomataacceptedlanguagecanbedescribedbycontextfreegrammar.(4).Pushdownautomataisequivalenttodeterministicfiniteautomata.(A).Only(1)and(2)areright.(B).Only(2)isright.(C).(1),(2),and(3)areright.(D).All(1),(2),(3),and(4)areright.

    68. Fortheequivalenceofpushdownautomatandcontextfreegrammar,whichofthefollowingstatementsareright:(1).Contextfreegrammarisequivalenttothepushdownautomatawhichcanacceptalanguagewithanemptystatestack.(2).Contextfreegrammarisequivalenttothepushdownautomatawhichcanacceptalanguagewithafinalstate.(3).(1)and(2)areequivalent.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).All(1),(2),and(3)areright.

    69. Whichofthefollowingstatementsmaybecorrect:(1).L={anbm,n<m}isadeterministiccontextfreelanguage.(2).L={anbm,n>m}isnotadeterministiccontextfreelanguage.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

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    70. Whichofthefollowingstatementsmaybecorrect:(1).IfL1isdeterministiccontextfreeandL2isregular,thenL1∩L2isnotdeterministiccontextfree.(2).IfL1isdeterministiccontextfreeandL2isregular,thentheunionofL1andL2isdeterministiccontextfree.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    71. Whichofthefollowingstatementarecorrect:(1).Acontextfreelanguageisasubsetofacontextsensitivelanguage.(2).It’seasiertoprocessregulargrammarthancontextfreegrammar.(3).It’seasiertoprocesscontextfreegrammarthancontextsensitivegrammar.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).All(1),(2),and(3)areright.

    72. Whichofthefollowingstatementsforcontextfreelanguagepumpinglemmamayberight:(1).Thepumpinglemmaisusefulinshowingthatalanguagedoesnotbelongtothefamilyofcontextfreelanguage.(2).Thesubstringthatprecedesboundedstringcanbearbitrarylong.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    73. Whichofthefollowingstatementsforlinearlanguagepumpinglemmamayberight:(1).Themiddlestringcanbeofarbitrarylength.(2).Thesubstringthatprecedesmiddlestringcanbearbitrarylong.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    74. Whichofthefollowingstatementsmayberight:(1).Thefamilyofcontextfreelanguageisapropersubsetofthefamilyoflinearlanguage.(2).Thefamilyoflinearlanguageisapropersubsetofthefamilyofcontextfreelanguage.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.

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    (D).Noneoftheaboveisright.

    75. Thefamilyofcontextfreelanguageisclosedunderthefollowingoperations:(1).Union,(2).Intersection,(3).Concatenation,(4).Star-closure,(5).Complementation.(A).(1),(2),and(3)areright.(B).(2),(3),and(4)areright.(C).(1),(3),and(4)areright.(D).(3),(4),and(5)areright.

    76. Whichofthefollowingstatementsmayberight:(1).Anintersectionofacontextfreelanguageandaregularlanguageisacontextfreelanguage.(2).Thefamilyofunambiguouscontextfreelanguagesisclosedunderunionoperation.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    77. Whichofthefollowingstatementscanberight:(1).Anintersectionofacontextfreelanguageandaregularlanguagemaynotbearegularlanguage.(2).Thefamilyoflinearlanguagesisnotclosedunderintersection.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    78. Whichofthefollowingstatementscanberight:(1).ThelanguageL={anbn:n≥0,nisnotamultipleof5}iscontextfree.(2).IfL1isacontextfreelanguageandL2isaregularlanguage,thereexistsanalgorithmtodeterminewhetherL1andL2haveacommonelement.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    79. Whichofthefollowingstatementsmayberight:(1).Thefamilyofcontextfreelanguageisnotclosedunderreversal.(2).Thereexistsanalgorithmtodetermineifacontextfreelanguagecontainsanyodd-lengthstrings.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

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    80. Whichofthefollowingstatementiscorrect:(1).Thefamilyoflinearlanguagesisclosed

    underconcatenationandnotclosedunderunion.(2).IfL1iscontextfreeandL2isregular,thenL1–L2iscontextfree.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    81. Whichofthefollowingstatementsarecorrect:(1).ATuringmachineisanabstract“machine”thatmanipulatessymbolsonastripoftapeaccordingtoatableofrules.(2).Turingmachineisamathematicalmodelthatdefinessuchadevice.(3).Turingmachineoperatesonaninfinitememorytapedividedintocells:write,moveleft/right,andhalt.(4).InsteadoftapeusedinoriginalTuringmachine,moderncomputersuserandomaccessmemorydesigntoperformcomputation.(A).(1)and(2)arecorrect.(B).(1),(2),and(3)arecorrect.(C).(1),(3),and(4)arecorrect.(D).All(1),(2),(3),and(4)arecorrect.

    82. ForaTuringmachine,whichofthefollowingstatementiscorrect:(1).ATuringmachineisdefinedbyM=(Q,Σ,Г,δ,q0,□,F),a7-tuple,andwecanthinkofaTuringmachineasasimplecomputer.(2).ThedifferencebetweenaTuringmachineandapushdownautomatonisinthetemporarymemory:arandomaccessmemoryisusedinTuringmachinewhileastackintheother.(A).Only(1)isright.(B).Only(2)isright.(C).Both(1)and(2)areright.(D).Noneoftheaboveisright.

    83. ThefunctionswhicharecomputablebyaTuringMachineareknownas(A).PartialRecursiveFunctions.(B).EnumerableFunctions.(C).PartialFunctions.(D).Finite-Automata.

    84. TheTuringmachineiscomputableiffinalstatecontains(A).transitionfunction.(B).notransitionfunction.(C).haltstate.(D).bothBandC.

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    85. ThelanguageL={ωω:ω∈(0,1)*}is

    (A).notacceptedbyaTuringmachine.(B).acceptedbysomeTuringmachines,butbynopushdownautomaton.(C).acceptedbysomepushdownautomaton,butnotcontextfree.(D).context-free,butnotregular.

    86. ForthedefinitionofastandardTuringmachine,whichofthefollowingstatementsareright:(A).TheTuringmachinehasatapethatisboundedinbothleftandrightdirections.(B).TheTuringmachineisdeterministicinthesensethatδdefinesatmostonemoveforeachconfiguration.(C).TuringmachineswithastayoptionareequivalenttoStandardTuringMachines.(D).All(A),(B),and(C).

    87. ForstandardTuringmachines,whichofthefollowingstatementsareright:(A).AteachmoveofaTuringmachine,thetapeheadmaymoveeitherleftorright.(B).Wecanaugmenteachmovewitha‘stay’option,i.e.wewilladd“don’tmove”totheset{L,R}.(C).TuringmachineswithastayoptionareequivalenttoStandardTuringMachines.(D).All(A),(B),and(C).

    88. WhatlanguageisacceptedbytheTuringmachinewhosetransitiongraphinthefigurebelow:(A).L=L(aabb*+bbbb*aa).(B).L=L(aab*b*+bbb*b*aa).(C).L=L(ab*+bb*a).(D).L=L(ab*λ+bb*a).

    89. The“high-level”descriptionforconstructingtheTuringmachinethatacceptthelanguageL={ωωRω}on{a,b}canbe:(1).Step1:3-splitinput;Step2:reverse-compareωagainstωRfollowedbyreverse-compareωRagainstω;Accepttheinputonlywhenbothstepsaresuccessful.(2).Step1:3-splitinputintoω1xω2xω3;Step2:forward-

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    compareωagainstωRandreverse-compareωRagainstω;Accepttheinputonlywhenbothstepsaresuccessful.(A).Only(1)iscorrect.(B).Only(2)iscorrect.(C).Both(1)and(2)arecorrect.(D).Noneoftheaboveiscorrect.

    90. Whichofthefollowingstatementcanbecorrect:(1).ForconstructingaTuringmachinethatcanperformadditionofpositiveintegersindecimalnotation,carryingdigit1tothehigherdigitsisdifferentfrombinarynumberaddition.(2).ATuringmachineforthemultiplicationoftwointegersmandncanbedonebyperformingmtimesofadditiontop=p+nwithp=0tostartwith.(A).Only(1)iscorrect.(B).Only(2)iscorrect.(C).Both(1)and(2)arecorrect.(D).Noneoftheaboveiscorrect.

    91. WhichofthefollowingstatementsonTuringmachinemodelscanbecorrect:(1).ATuringmachinecanhaveasemi-infinitetape.(2).TheTuringmachinecanbeimplementedoff-line,readstatefrominputfile.(3).Turingmachinecanbeimplementedtohavemultidimensionalstorage.(A).(1)and(2)arecorrect.(B).(2)and(3)arecorrect.(C).(1)and(3)arecorrect.(D).(1),(2),and(3)arecorrect.

    92. SupposewemaketherequirementthataTuringmachinecanhaltonlyinafinalstate,thatis,weaskthatδ(q,a)bedefinedforallpairs(q,a)withaϵΓandq∉F.Whichofthefollowingarecorrect:(1).ThiswillrestrictthepoweroftheTuringmachine.(2)ThiswillnotrestrictthepoweroftheTuringmachine.(3).Anynon-finalhaltingstatecanbeputintoaninfiniteloop.(4).δ(q,a)=(q,a,S)forallaϵΓandq∉F.(A).(1)and(3)arecorrect.(B).(2)and(3)arecorrect.(C).(1),(3),and(4)arecorrect.(D).(2),(3),and(4)arecorrect.

    93. IfwemaketherestrictionthataTuringmachinemustalwayswriteasymboldifferentfromtheoneitreads,i.e.ifδ(qi,a)=(qi,b,LorR)thenaandbmustbedifferent.Whichofthefollowingareright:(1).Thiswillreducethepoweroftheautomaton.(2).Thiswill

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    notreducethepoweroftheautomaton.(3).ForeachsymbolaϵΓ,wecanintroduceapseudo-symbolA.Wheneverwe(A).(1)and(3)arecorrect.(B).(2)and(3)arecorrect.(C).Only(3)iscorrect.(D).Noneofaboveiscorrect.

    94. WhichofthefollowingstatementsonnondeterministicTuringmachinearecorrect:(1).AnondeterministicTuringmachineislessusefulsinceitisnotdeterministic,i.e.wemaynotbeabletoreachafixedfinalcomputationstate.(2).Wheneverthenondeterministicmachineperformsatransitionthatinvolvesmorethanonemove,thedeterministicmachinewillsimulateitbycreatinganactiveconfigurationforeachofthecorrespondingcomputationsonthetape.(3).Thedeterministicmachinewillrepeatedlyexecuteasinglesteponeachofthesegeneratedconfigurationsinturn.(4).Ifanyofthecomputationsenterahaltstate,thedeterministicmachinewillidentifyitasinactiveandremovefromfurtherconsideration.(A).(1),(2),and(3)arecorrect.(B).(2),(3),and(4)arecorrect.(C).(1),(3),and(4)arecorrect.(D).(1),(2),(3),and(4)arecorrect.

    95. Todeterminewhetherornotastringin{0,1}+representsanencodedTuringmachine,whichofthefollowingarecorrect:(1).Todetermineifagivenstringin{0,1}+representsatransitionfunctionδ(qi,ak)=(qj,al,LorR)foranencodedTurningmachine.(2).Wecancheckthattheinputisoftheform0x10x20x30x40x50,wherethexiarestringsof1's,withtherestrictionthatx5=1or11.(3).Wemustuseapredefinedpushdownmachinetoguaranteetherightgrammarimplementation.(A).(1)and(2)arecorrect.(B).(2)and(3)arecorrect.(C).(1),(2),and(3)arecorrect.(D).Noneoftheaboveiscorrect.

    96. Whichofthefollowingstatementsofrecursivelyenumerablelanguagearecorrect:(1).Allrecursivelanguagesarecontextsensitive.(2).IfLisafinitelanguage,thenL+isrecursivelyenumerable.(3).Ifalanguageisnotrecursivelyenumerable,itscomplementcannotberecursive.(A).(1)and(2)arecorrect.(B).(2)and(3)arecorrect.(C).(1),(2),and(3)arecorrect.(D).Noneoftheaboveiscorrect.

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    97. Whichofthefollowingarecorrect:(1).Ifanalgorithmofatwo-tapeTuringmachinehasO(n)complexity,thenthebestofwecangetforaone-tapemachineisO(n2).(2).Anycomputationthatcanbeperformedonasingle-tape,off-lineTuringmachineintimeO(T(n))alsocanbeperformedonastandardTuringmachineintimeO(T(n)).(A).Only(1)iscorrect.(B).Only(2)iscorrect.(C).Both(1)and(2)arecorrect.(D).Noneoftheaboveiscorrect.

    98. Whichofthefollowingstatementsoftheunionofrecursivelyenumerablelanguagesarecorrect:(1).Thefamilyofrecursivelyenumerablelanguagesisclosedunderunion.(2).Whenrepresentedwithaninputω,wecannondeterministicallychooseTuringmachinesM1orM2toprocessω.TheresultisaTuringmachinethatacceptstwolanguagesL1∪L2.(A).(1)iscorrect.(B).(2)iscorrect.(C).(1)and(2)arecorrect.(D).Noneoftheaboveiscorrect.

    99. Forsortingefficiency,whichofthefollowingarecorrect:(1).Thechoiceofalgorithmisimportantinsorting.(2).Simplemethods,suchasabubblesort,havetime-complexityO(n2).(3).Themostefficientsortingalgorithmshavetime-complexityO(logn).(A).(1)and(2)arecorrect.(B).(2)and(3)arecorrect.(C).(1),(2),and(3)arecorrect.(D).Noneoftheaboveiscorrect.

    100. WhichofthefollowingareNP-completeproblems:(1).Graphcoloringproblem.(2).Hamiltonianpathproblem.(3).Knapsackproblem.(4).Travellingsalesmanproblem.(5).Problemofnetworkshortestpathfindingbetweentworouters.(A).(1),(2),and(3).(B).(2),(3),and(4).(C).(1),(3),and(5).(D).(1),(2),(3),and(4).