系统级编程选择题集

MultipleChoiceQuiz21分数:8/8Whichofthefollowingcouldberepresentedbyonebitofinformation?选择一个答案a.thepositionofalightswitchb.anASCIIcharacterc.thecolorofasinglepixelonatrue-colorcomputerdisplayd.thecurrentchannelofatelevisionreceiver正确这次提交的分数：8/8。Question2分数:8/8InC,whatisthefollowingbinarynumberinhexadecimal?11010101选择一个答案a.0xD5b.0xB5c.0xABd.0x5D正确这次提交的分数：8/8。Question3分数:8/8WhatisthevalueofthefollowingCexpression?0x1234^0x5432选择一个答案a.0x4606b.0x5636c.0x1030d.0x5434正确这次提交的分数：8/8。Question4分数:8/8WhatisthevalueofthefollowingCexpression?0x1234&0x5432选择一个答案a.0x1030b.0x1111c.0x5636d.0x6666正确这次提交的分数：8/8。Question5分数:8/8Howis46(decimal)representedinan8-bit2'scomplementbinaryformat?选择一个答案a.01000110b.00101100c.00101110d.00011110正确这次提交的分数：8/8。Question6分数:8/8Howis-10(decimal)representedinan8-bit2'scomplementbinaryformat?选择一个答案a.11111010b.11110101c.10001010d.11110110正确这次提交的分数：8/8。Question7分数:8/8Inacomputerwith4-bytewords,whichofthefollowingCexpressionstestswhetherptrcontainstheaddressofaword?I.(ptr&3)==0II.(ptr|3)==0III.(ptr%4)==0选择一个答案a.IIIonlyb.IIonlyc.Ionlyd.IandIIIonly正确这次提交的分数：8/8。Question8分数:8/8WhathappensinaCprogramwhenanadditionwouldcauseintegeroverflow?选择一个答案a.Thecorrectvalueiscoercedtoafloatingpointnumber.b.Anincorrectresultisproducedandexecutioncontinues.c.Anexception-handleriscalledwiththetwooperandsasparameters.d.Executionisterminated.正确这次提交的分数：8/8。Question9分数:8/8Whatisthepurposeoftheexponentinfloatingpointnumbers?选择一个答案a.tospecifythesuperscriptb.tospecifythebaseasbinary,octal,orhexadecimalc.themantissaisraisedtothepoweroftheexponentd.toindicatewherethedecimalorbinarypointshouldbe正确这次提交的分数：8/8。Question10分数:8/8Whichofthefollowingstatementsaboutfloating-pointnumbersinCistrue?I.Floating-pointnumbersareoftenonlyapproximationsofrealnumbers.II.A32-bitfloatonlyapproximatesdecimalfractions,buta64-bitdoublerepresentsthemexactly.III.Floating-pointnumberscanrepresentanyrationalrealnumberbutnotirrationals.选择一个答案a.IandIIIonlyb.IandIIonlyc.IIonlyd.Ionly正确这次提交的分数：8/8。Question11分数:8/8Whichofthefollowingnumericaloperationsismostlikelytoleadtolossofprecision?选择一个答案a.Integeradditionb.Floating-pointadditionc.Floating-pointmultiplicationd.Integermultiplication正确这次提交的分数：8/8。Question12分数:8/8InC,usingdefaultfloatingpointsettings,whathappenswhenafloating-pointcomputationresultsinanoverflow?选择一个答案a.Anerroneousvalueiscomputedandexecutioncontinues.b.Aspecialvalueinfinityiscomputed,testablewith_finite().c.Anexceptionisraisedunlessdisabledbycalling_controlfp().d.Programexecutionishalted.正确这次提交的分数：8/8。MultipleChoiceQuiz31分数:7/7Theprogramcountercontains选择一个答案a.thenumberoftimesaprogramhasbeenexecutedb.theaddressoftheCPUinstructionthatisabouttobefetchedc.thenumberofCPUinstructionsaprogramhasexecutedsofard.theamountofmemoryaprogramiscurrentlyusing正确这次提交的分数：7/7。回复历史：#动作回答时间原始分数成绩1评分theaddressoftheCPUinstructionthatisabouttobefetched15年09月24日的12:59:14772关闭theaddressoftheCPUinstructionthatisabouttobefetched15年09月24日的13:02:5077Question2分数:7/7ImmediatelyaftertheCPUexecutesaninstructionthatisneitherabranchnorajumpinstruction,theprogramcounter选择一个答案a.isincrementedbyoneb.isincrementedtopointtothefollowinginstructionc.hasavaluethatcannotbedeterminedwithoutfurtherinformationd.remainsunchanged正确这次提交的分数：7/7。Question3分数:7/7ACPUregisterisawordofCPUmemorythat选择一个答案a.housesacriticalvariableforthedurationoftheexecutionofaprogramb.isexplicitlyloadedandunloadedfromnormalmemorybycompiler-generatedinstructionsc.recordstheresultsofperiodicCPUdiagnosticsd.isautomaticallyloadedwhenaCPUinstructionreferstoawordofnormalmemory正确这次提交的分数：7/7。Question4分数:7/7WhichofthefollowingcomputationsmaybeperformedbyexactlyoneCPUinstruction?1.a=5;2.a=b+c*5;3.for(i=0;i10;i+=a[i++]);选择一个答案a.Ionlyb.IIonlyc.I,II,andIIId.IandIIonly正确这次提交的分数：7/7。Question5分数:8/8Supposethat,usingatoolsuchasthememorywindowofVisualC++,wefoundthatacertainsetofcontiguousmemorylocationscontainedtheinteger0xC605CD623A8365000000.Whatcouldthesememorylocationshold?1.theinteger0xC605CD623A83650000002.astring3.aCPUinstruction选择一个答案a.Ionlyb.I,II,andIIIc.IandIIonlyd.IIIonly正确这次提交的分数：8/8。Question6分数:8/8Abranchinstruction选择一个答案a.setstheprogramcountertooneofmanypossiblevaluesb.unconditionallysetstheprogramcountertoitsoperandc.setstheprogramcountertooneoftwopossiblevaluesd.increasestheprogramcounterbyafixedamount正确这次提交的分数：8/8。Question7分数:8/8Ajumpinstruction选择一个答案a.changesapointertopointtothenextelementofanarrayb.changestheprogramcounteronlyifitsoperandisequaltozeroc.increasestheprogramcounterd.unconditionallysetstheprogramcountertoitsoperand正确这次提交的分数：8/8。Question8分数:8/8Themachinecodegeneratedfromsourcecodebyacompiler选择一个答案a.doesnotpreservealltheinformationgiveninthesourcecodeb.canbeeasilyinspectedtocheckthecorrectnessofthecompilerc.executesmorequicklythanthesourcecoded.associatesvariablevalueswiththeirnames正确这次提交的分数：8/8。Question9分数:8/8Whichofthefollowingaretrueoftheeffectthatoptimizationshaveonthemachinecodegeneratedbycompilers?I.Theresultingcodewillbefasterand/orsmaller.II.Theresultingcodewillbeclearer.III.Theresultingcodewillbehar