addressbeginning

beginning  时间:2021-05-17  阅读:()
BeginningCforEngineersFall2005Instructor:BettinaSchimanskiTAs:GabeMulley&JoelDeverWebsite:www.
cs.
rpi.
edu/~schimb/beginC2005Lecture1–Section2(8/31/05)Section4(9/1/05)OverviewCourseGoalsIntroductionUnixandtheHistoryofCFirstCProgramDataTypesandexpressionsI/OCourseGoalsIntroducegeneralconceptsofprogrammingBegintothinklikeaprogrammerStartprogramminginCWhyisthisimportantTounderstandbasiccomputerconceptsToappreciatestructuredprogrammingWillserveasabasisforanyfutureprogrammingyoudoNeededfortheLaboratoryIntroductiontoEmbeddedControl(LITEC)course–ENGR2350WhatisprogrammingGivenawell-definedproblem:FindanalgorithmtosolveaproblemExpressthatalgorithminawaythatthecomputercanexecuteitAnalgorithmisasequenceofinstructionstosolveaproblemsuchthat:EachinstructionisunambiguousandissomethingthecomputercandoAfteraninstructionisfinishedthereisnoambiguityaboutwhichinstructionistobeexecutednextExecutionfinishesinafinitenumberofstepsThedescriptionofthealgorithmisfiniteCProgrammingLanguageEvolvedfromBCPL(1967)andB(1969)ByDennisRitchieatBellLabsBythelate1970sitwaswidelyusedStandardizedin1989intheUSthroughtheAmericanNationalStandardsInstitute(ANSI)andworldwidethroughInternationalStandardsOrganization(ISO)C++isasupersetofCCStandardLibraryCprogramsconsistofmanyfunctionsCStandardLibrary-collectionofexistingfunctionsProgramminginCisacombinationof:CreatingyourownfunctionsUsingCStandardLibraryfunctionsCPortabilityCishardware-independentApplicationsinCcanrunwithlittleornomodificationsonawiderangeofcomputersystemsUseANSIstandardlibraryfunctionsinsteadofyourownequivalentRAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerArchitectureofaComputerI/OdevicesInputOutputCPUALUMainMemorySecondaryStorageI/ODevicesCommunicationswiththeoutsideworldInputdevices:keyboardmousejoystickscannermicrophoneOutputdevices:screenprintercomputerspeakersnetworksRAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputer"Administrative"sectionofthecomputer–supervisesoperations:controlsI/OandALUHas2componentstoexecuteprograminstructionsArithmetic/LogicUnitperformsarithmeticoperations,andmakeslogicalcomparisonsControlUnitcontrolstheorderinwhichyourprograminstructionsareexecutedUsesoneormoreregistersasscratchspaceforstoringnumbersbetweeninstructionsAtypicalCPUtodaycanexecutemillionsofarithmeticoperationsinasecondRAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerCentralProcessingUnit(CPU)RAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerCentralProcessingUnit(CPU)RAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerCentralProcessingUnit(CPU)ManycomputersnowhavemultipleCPUs(multiprocessors)andcanthereforeperformmanyoperationsatatimeMainMemorySometimescalledrandomaccessmemory(RAM).
Storesthenumbers(data)thataprogramuseswhenitrunsonthecomputer.
Containsmillionsofcircuitswhichareeitherofforon(0or1)BinaryAlsostorestheinstructionsoftheprogramthatisrunningonthecomputer.
Dividedintofixedsizeunitsofmemorycalledwords.
eachwordstoresonenumbereachwordhasitsownaddressRAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerDataProgramInstructionsMainMemoryRAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerDataProgramInstructionsSecondaryStoragePermanentstorageusedtosavedataandprogramswhentheyarenotrunningonthecomputer.
Dataandprogramsareorganizedintovaryingsizeunitscalledfiles.
Filesareorganizedintodirectoriesthatcancontainsubdirectories.
SecondarystorageischeaperperMegabytethanmainmemory,butaccesstodataismuchslowerRAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerSecondaryStorageRAM(memory)I/ODevicesCentralProcessingUnit(CPU)SecondaryStorageRegistersComputerTheProgrammingProcessUseaneditor(suchasEmacs,Notepad,Vi,etc.
)tocreateaprogramfile(sourcefile)containsthetextoftheprogramwritteninsomeprogramminglanguage(likeC)UseapreprocessortoincludethecontentsofotherfilesUseacompilertoconvertthesourcefileintoamachinecodefile(objectfile)convertfrom"English"tobinarywithmachineoperationsUsealinkertoconverttheobjectfileintoanexecutablefile.
includeothermachinecodethattheprogramrequiresRuntheexecutablefileCreatingaCProgramACprogramisasetoffunctionsthatcollectivelysolveagivenproblem.
eachfunctionisasequenceofCstatements(instructions)executionalwaysbeginswithafunctionnamed"main"onefunctioncallsanotherfunctiontogetittoexecuteitsstatementsTheCstatementsinafunctionareexecutedoneaftertheotherinsequentialorderaswritten.
EachCstatementisendedbyasemi-colon.
FirstCProgramAnythingbetween/*and*/isacommentintendedtoimprovethereadabilityoftheprogram.
#includeisusedtotellthecompilerandlinkerwhatlibraryresourcestheprogramuses.
thelibrarydefineseverythingyouneedtodisplaymessagesonthescreenThisprogramcontainsonefunctionnamed"main".
Noticewheresemi-colonsareplaced.
Theprogramoutputs(printstothescreen)thewordsHello,World!
/*BettinaSchimanskiHelloWorldProgramprog01a.
cAugust31,2005*/#includeintmain(){printf("Hello,World!
\n");return0;}DisplayingMessagesOnTheScreen:UsingprintfTodisplayamessageonthecomputerscreenusetheprintfstatement.
Thebackslash"\"indicatesanescapesequence.
Thismeanstakethealternatemeaningofwhateverimmediatelyfollowsit.
\nmeanstostartanewline\tisatab\"isaquote\aisanaudiblealert(bell)Textstringsmustalwaysbesurroundedbydoublequotes.
printf("Hello,World\n");MoreExamplesprintf("Hello\nWorld!
\n");printf("\tFirstpartoflongmessage.
");printf("Secondpartoflongmessage.
\n");printf("\"Hello\"World!
"\n");HelloWorld!
Firstpartoflongmessage.
Secondpartoflongmessage.
"Hello"World!
"DefiningaCFunctionACfunctionhasthefollowingform:Thenameofthisfunctionis"main".
Theword"int"meansthatthisfunctionreturnsanintegernumber.
using0toindicatethattheprogramrancorrectly.
thisiswhatthereturnstatementdoesattheendofthefunctionThebracesdefinethebeginningandtheendofthefunction.
Thefirstlineofthefunctioniscalledthefunctionheader.
intmainsequenceofstatementsseparatedbysemicolonsreturn0;}FirstLab!
Gotohttp://www.
cs.
rpi.
edu/~schimb/beginC2005ClickonLectures&LabsandgotoLab1DojustPart1StandardDataTypesinCAdatatypetellswhattypeofdataisstoredinagivenmemorylocation.
StandardCdatatypesarebrokenintothefollowingtypes:IntegralTypesrepresentwholenumbersandtheirnegativesdeclaredasint,short,orlongFloatingTypesrepresentrealnumberswithadecimalpointdeclaredasfloat,ordoubleCharacterTypesrepresentsinglecharactersdeclaredascharCVariablesVariablesinCstoredatainmemorysothatthedatacanbeaccessedthroughouttheexecutionofaprogramAvariablestoresdatacorrespondingtoaspecifictype.
EachvariablethataCprogramusesmustbedeclaredatthebeginningofthefunctionbeforeitcanbeused.
specifythetypeofthevariablenumerictypes:intshortlongfloatdoublecharactertype:charspecifyanameforthevariableanypreviouslyunusedCidentifiercanbeused(withsomemoreexceptionsdiscussedlater)intx;floatsum,product;WhatDoesaVariableDeclarationDoAdeclarationtellsthecompilertoallocateenoughmemorytoholdavalueofthisdatatype,andtoassociatetheidentifierwiththislocation.
intapartmentNumber;floattax_rate_Y2K;charmiddleInitial;4bytesfortaxRateY2K1byteformiddleInitialVariableandfunctionNamesInCSomereservedwordsinC:breakcasecharconstcontinuedefaultdodoubleelseenumfloatforgotoifintlongreturnshortsignedstaticstructswitchtypedefunionunsignedvoidwhileVariablesandfunctionnamesinCarecalledidentifiers.
identifiersareusedformanyotherthingsaswellRulesforconstructingvalididentifiersinC:cancontainletters(upperandlowercase),digits,andtheunderscore(_)charactercannotstartwithadigitcannotbeareservedwordcanbeatmost256characterslong,thoughsomecompilersonlylookatfirst32charactersarecasesensitiveIdentifiersVALIDapartment_numbertax_rate_Y2KPrintHeadingageOfHorse_NOTVALID(Why)apartment#2000TaxRateAge-Of-Catdayofweek**UsingmeaningfulvariablenamesisagoodprogrammingpracticeGivingaValuetoaVariableYoucanassign(give)avaluetoavariablebyusingtheassignmentoperator=VARIABLEDECLARATIONScharmiddleInitial;charletter;intapartmentNumber;VALIDASSIGNMENTSTATEMENTSmiddleInitial='K';letter=middleInitial;apartmentNumber=8;AssignmentStatementAnassignmentstatementisusedtoputavalueintoavariable.
ThepreviousvalueisreplacedSyntax:=;isanydeclaredvariableintheprogramisanythingthatproducesavalueoftheappropriatetype(moreonthislater)first,theexpressiononrightisevaluated.
thentheresultingvalueisstoredinthememorylocationofvariableonleft.
Examples:count=10;count=count+1;area=3.
14*radius*radius;NOTE:AnautomatictypecoercionoccursafterevaluationbutbeforethevalueisstoredifthetypesdifferforexpressionandvariableExamplesArithmeticExpressionsWithIntegers(int,long)Operators:resultisalwaysanintegerSymbolNameExampleValue(x=10,y=3)+additionx+y13–subtractionx–y7*multiplicationx*y30/quotientx/y3%remainderx%y1–unaryminus–x-10+unaryplus+x10ArithmeticExpressionsContinued…Youcanstringtheoperatorstogethertobuildlongerexpressions.
useparenthesestospecifyorderofoperationsprecedence(aftersub-expressionsinparentheses):first:unaryplusandminusfromrighttoleftsecond:*and/and%fromlefttorightthird:+and–fromlefttorightArithmeticExpressionExampleinty=2;intz;z=-y*3*(4+5)%10+--3;-2*3*9%10+--3-2*3*9%10+3-6*9%10+3-54%10+3-4+3-1ArithmeticExpressionsWithReals(float,double)Arithmeticexpressionswithrealnumbers(numberswithdecimalpoints)workthesamewayaswithintegers,withafewexceptions:thereisnoremainderoperator("%")the"/"operatormeans"divide"(vsquotient),computingtheanswertomanydecimalplacestheresultisarealvalueratherthananintegervalueImportant:Realvaluesareapproximateandmaycontainerrorsinthelastfewdigits.
about7digitsofaccuracyfortypefloatabout14digitsofaccuracyfortypedoubleMixedModeArithmeticExpressionsArithmeticexpressions:bothintegersandfloatscangettricky.
ifbothoperandsareintegers,integerarithmeticisusedifeitheroperandisafloat,floatarithmeticisusedanintegeroperandisconvertedtofloatfortheoperationExamples:inta,x;x=3.
59;/*xgetsthevalue3(norounding)*/floaty=3;/*ygetsthevalue3.
0*/a=12;/*agetsthevalue12*/floatavg=(a+x)/2;/*avggetsthevalue7.
0…UHOH!
!
!
*/PrintingvariablesandconstantstothescreenwithprintfUsethefollowingconversionspecifications:%dforaninteger%ldforalonginteger%cforacharacter%fforafloat%fforadoubleExample:Output:intsum=5;floatavg=12.
2;charch='A';printf("Thesumis%d\n",sum);Thesumis5printf("avg=%f"\n",avg);avg=12.
2prinf("ch=%c\n",ch);ch=Aprintf("%d,%f,%c\n",sum,avg,ch);5,12.
2,Aprintf("%d\n",5);5Note:seep.
153inyourtextbookforacompletelistofalldatatypesReadingdatafromthekeyboardwithscanfUsedtoassignavaluetypedonthekeyboardtoavariable.
Usedsimilarlytoprintf.
Youmustusethefollowingconversionspecifications:DataTypeprintfconverstionspec.
scanfconversionspec.
int%d%dlong%ld%ldfloat%f%fdouble%f%lfchar%c%ccharacterstring%s%sTheusermusttypeavaluefollowedbytheEnterKey.
Ex:scanf("%d",&num);Example:ProgramtofindtheaverageoftwonumbersNotethatyoucandeclaremorethanonevariableperline.
Wedivideby2.
0insteadof2sothattherighthandsideisafloat(i.
e.
notruncationtakesplace)scanfisusedsimilarlytoprintf,exceptthatyouneedtoputanampersand(&)beforethevariablenameThefirstargumentofthescanffunctionistheconversionspecifier(s)inquotes,thenthevariablename(s)#includeintmain(){intnum1,num2;floatavg;/*gettwoinputs*/printf("Enterthefirstinteger:");scanf("%d",&num1);printf("Enterthesecondinteger:");scanf("%d",&num2);/*computeandprinttheavg*/avg=(num1+num2)/2.
0;printf("Theaverageis%f\n",avg);return0;}FinishLab1Gotohttp://www.
cs.
rpi.
edu/~schimb/beginC2005ClickonLectures&LabsandgotoLab1DoPart2HomeworkReadChapters1,2and9Dueatthebeginningofnextclass:HW1AcademicIntegrityStatementFYI:InfoonCygwin,Putty,SecureCRT,andEmacsareonthewebsite

RackNerd提供四款高配美国服务器促销活动低至月$189

RackNerd 商家给的感觉就是一直蹭节日热点,然后时不时通过修改配置结构不断的提供低价年付的VPS主机,不过他们家还是在做事的,这么两年多的发展,居然已经有新增至十几个数据中心,而且产品线发展也是比较丰富。比如也有独立服务器业务,不过在他们轮番的低价年付VPS主机活动下,他们的服务器估摸着销路不是太好的。这里,今天有看到RackNerd商家的独立服务器业务有促销。这次提供美国多个机房的高配独立...

宝塔面板企业版和专业版618年中活动 永久授权仅1888元+

我们一般的站长或者企业服务器配置WEB环境会用到免费版本的宝塔面板。但是如果我们需要较多的付费插件扩展,或者是有需要企业功能应用的,短期来说我们可能选择按件按月付费的比较好,但是如果我们长期使用的话,有些网友认为选择宝塔面板企业版或者专业版是比较划算的。这样在年中大促618的时候,我们也可以看到宝塔面板也有发布促销活动。企业版年付899元,专业版永久授权1888元起步。对于有需要的网友来说,还是值...

IMIDC(rainbow cloud):香港/台湾/日本/莫斯科独立服务器特价,闪购大促销,最低30usd/月起

imidc怎么样?imidc彩虹网路,rainbow cloud知名服务器提供商。自营多地区数据中心,是 Apnic RIPE Afrinic Arin 认证服务商。拥有丰富的网路资源。 在2021年 6.18 开启了输血大促销,促销区域包括 香港 台湾 日本 莫斯科 等地促销机型为 E3係,参与促销地区有 香港 日本 台湾 莫斯科 等地, 限量50台,售罄为止,先到先得。所有服务器配置 CPU ...

beginning为你推荐
腾讯周鸿祎legraph产业2014年2月25日支持ipad支持ipad支持ipad联通版iphone4s苹果4s是联通版,或移动版,或全网通如何知道?csshackcss常见的hack方法有哪些chromeframe谷歌浏览器(Chrome) 与(Chromium) 有什么区别?哪个更快?google分析怎样学会使用谷歌分析? 我自己想往网站分析走。
shopex虚拟主机 俄罗斯vps 美国主机排名 187邮箱 新加坡主机 plesk a2hosting 大硬盘 t楼 webhostingpad 163网 permitrootlogin sockscap 外国空间 mobaxterm 免费smtp服务器 中国智能物流骨干网 百兆独享 中国电信测网速 129邮箱 更多