界面设计很Low,对颜色布局设计很菜,没感觉,功能简单,对于毕设足以。
其中包括一些部分功能的小Demo测试,比如官方侧滑菜单、地址分类导航、自定义手势密码、百度定位、图灵机器人聊天问答等
2025/11/28 11:07:31 5.31MB Android 电影票 购票App
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编译原理龙书答案完整性高第二章2.2ExercisesforSection2.22.2.1Considerthecontext-freegrammar:S->SS+|SS*|aShowhowthestringaa+a*canbegeneratedbythisgrammar.Constructaparsetreeforthisstring.Whatlanguagedoesthisgrammargenerate?Justifyyouranswer.answerS->SS*->SS+S*->aS+S*->aa+S*->aa+a*L={Postfixexpressionconsistingofdigits,plusandmultiplesigns}2.2.2Whatlanguageisgeneratedbythefollowinggrammars?Ineachcasejustifyyouranswer.S->0S1|01S->+SS|-SS|aS->S(S)S|εS->aSbS|bSaS|ε⧗S->a|S+S|SS|S*|(S)answerL={0n1n|n>=1}L={Prefixexpressionconsistingofplusandminussigns}L={Matchedbracketsofarbitraryarrangementandnesting,includesε}L={Stringhasthesameamountofaandb,includesε}?2.2.3WhichofthegrammarsinExercise2.2.2areambiguousanswerNoNoYesYesYes2.2.4Constructunambiguouscontext-freegrammarsforeachofthefollowinglanguages.Ineachcaseshowthatyourgrammariscorrect.Arithmeticexpressionsinpostfixnotation.Left-associativelistsofidentifiersseparatedbycommas.Right-associativelistsofidentifiersseparatedbycommas.Arithmeticexpressionsofintegersandidentifierswiththefourbinaryoperators+,-,*,/.answer1.E->EEop|num2.list->list,id|id3.list->id,list|id4.expr->expr+term|expr-term|termterm->term*factor|term/factor|factorfactor->id|num|(expr)5.expr->expr+term|expr-term|termterm->term*unary|term/unary|unaryunary->+factor|-factorfactor->id|num|(expr)2.2.5Showthatallbinarystringsgeneratedbythefollowinggrammarhavevaluesdivisibleby3.Hint.Useinductiononthenumberofnodesinaparsetree.num->11|1001|num0|numnumDoesthegrammargenerateallbinarystringswithvaluesdivisibleby3?answerproveanystringderivedfromthegrammarcanbeconsideredtobeasequenceconsistingof11,1001and0,andnotprefixedwith0.thesumofthisstringis:sum=Σn(21+20)*2n+Σm(23+20)*2m=Σn3*2n+Σm9*2mItisobviouslycandivisibleby3.No.Considerstring"10101",itisdivisibleby3,butcannotderivedfromthegrammar.Question:anygeneralprove?2.2.6Constructacontext-freegrammarforromannumerals.Note:wejustconsiderasubsetofromannumeralswhichislessthan4k.answerwikipedia:Roman_numeralsviawikipedia,wecancategorizethesinglenomannumeralsinto4groups:I,II,III|IV|V,VI,VII,VIII|IXthengettheproduction:digit->smallDigit|IV|VsmallDigit|IXsmallDigit->I|II|III|εandwecanfindasimplewaytomapromantoarabicnumerals.Forexample:XII=>X,II=>10+2=>12CXCIX=>C,XC,IX=>100+90+9=>199MDCCCLXXX=>M,DCCC,LXXX=>1000+800+80=>1880viatheuppertworules,wecanderivetheproduction:romanNum->thousandhundredtendigitthousand->M|MM|MMM|εhundred->smallHundred|CD|DsmallHundred|CMsmallHundred->C|CC|CCC|εten->smallTen|XL|LsmallTen|XCsmallTen->X|XX|XXX|εdigit->smallDigit|IV|VsmallDigit|IXsmallDigit->I|II|III|ε2.3ExercisesforSection2.32.3.1Constructasyntax-directedtranslationschemethattrans­latesarithmeticexpressionsfrominfixnotationintoprefixnotationinwhichanoperatorappearsbeforeitsoperands;e.g.,-xyistheprefixnotationforx-y.Giveannotatedparsetreesfortheinputs9-5+2and9-5*2.。
answerproductions:expr->expr+term|expr-term|termterm->term*factor|term/factor|factorfactor->digit|(expr)translationschemes:expr->{print("+")}expr+term|{print("-")}expr-term|termterm->{print("*")}term*factor|{print("/")}term/factor|factorfactor->digit{print(digit)}|(expr)2.3.2Constructasyntax-directedtranslationschemethattrans­latesarithmeticexpressionsfrompostfixnotationintoinfixnotation.Giveannotatedparsetreesfortheinputs95-2*and952*-.answerproductions:expr->exprexpr+|exprexpr-|exprexpr*|exprexpr/|digittranslationschemes:expr->expr{print("+")}expr+|expr{print("-")}expr-|{print("(")}expr{print(")*(")}expr{print(")")}*|{print("(")}expr{print(")/(")}expr{print(")")}/|digit{print(digit)}AnotherreferenceanswerE->{print("(")}E{print(op)}E{print(")"}}op|digit{print(digit)}2.3.3Constructasyntax-directedtranslationschemethattrans­latesintegersintoromannumeralsanswerassistantfunction:repeat(sign,times)//repeat('a',2)='aa'translationschemes:num->thousandhundredtendigit{num.roman=thousand.roman||hundred.roman||ten.roman||digit.roman;print(num.roman)}thousand->low{thousand.roman=repeat('M',low.v)}hundred->low{hundred.roman=repeat('C',low.v)}|4{hundred.roman='CD'}|high{hundred.roman='D'||repeat('X',high.v-5)}|9{hundred.roman='CM'}ten->low{ten.roman=repeat('X',low.v)}|4{ten.roman='XL'}|high{ten.roman='L'||repeat('X',high.v-5)}|9{ten.roman='XC'}digit->low{digit.roman=repeat('I',low.v)}|4{digit.roman='IV'}|high{digit.roman='V'||repeat('I',high.v-5)}|9{digit.roman='IX'}low->0{low.v=0}|1{low.v=1}|2{low.v=2}|3{low.v=3}high->5{high.v=5}|6{high.v=6}|7{high.v=7}|8{high.v=8}2.3.4Constructasyntax-directedtranslationschemethattrans­latesromannumeralsintointegers.answerproductions:romanNum->thousandhundredtendigitthousand->M|MM|MMM|εhundred->smallHundred|CD|DsmallHundred|CMsmallHundred->C|CC|CCC|εten->smallTen|XL|LsmallTen|XCsmallTen->X|XX|XXX|εdigit->smallDigit|IV|VsmallDigit|IXsmallDigit->I|II|III|εtranslationschemes:romanNum->thousandhundredtendigit{romanNum.v=thousand.v||hundred.v||ten.v||digit.v;print(romanNun.v)}thousand->M{thousand.v=1}|MM{thousand.v=2}|MMM{thousand.v=3}|ε{thousand.v=0}hundred->smallHundred{hundred.v=smallHundred.v}|CD{hundred.v=smallHundred.v}|DsmallHundred{hundred.v=5+smallHundred.v}|CM{hundred.v=9}smallHundred->C{smallHundred.v=1}|CC{smallHundred.v=2}|CCC{smallHundred.v=3}|ε{hundred.v=0}ten->smallTen{ten.v=smallTen.v}|XL{ten.v=4}|LsmallTen{ten.v=5+smallTen.v}|XC{ten.v=9}smallTen->X{smallTen.v=1}|XX{smallTen.v=2}|XXX{smallTen.v=3}|ε{smallTen.v=0}digit->smallDigit{digit.v=smallDigit.v}|IV{digit.v=4}|VsmallDigit{digit.v=5+smallDigit.v}|IX{digit.v=9}smallDigit->I{smallDigit.v=1}|II{smallDigit.v=2}|III{smallDigit.v=3}|ε{smallDigit.v=0}2.3.5Constructasyntax-directedtranslationschemethattrans­latespostfixarithmeticexpressionsintoequivalentprefixarithmeticexpressions.answerproduction:expr->exprexprop|digittranslationscheme:expr->{print(op)}exprexprop|digit{print(digit)}ExercisesforSection2.42.4.1Constructrecursive-descentparsers,startingwiththefollow­inggrammars:S->+SS|-SS|aS->S(S)S|εS->0S1|01Answer1)S->+SS|-SS|avoidS(){switch(lookahead){case"+":match("+");S();S();break;case"-":match("-");S();S();break;case"a":match("a");break;default:thrownewSyntaxException();}}voidmatch(Terminalt){if(lookahead=t){lookahead=nextTerminal();}else{thrownewSyntaxException()}}2)S->S(S)S|εvoidS(){if(lookahead=="("){S();match("(");S();match(")");S();}}3)S->0S1|01voidS(){switch(lookahead){case"0":match("0");S();match("1");break;case"1"://match(epsilon);break;default:thrownewSyntaxException();}}ExercisesforSection2.62.6.1ExtendthelexicalanalyzerinSection2.6.5toremovecom­ments,definedasfollows:Acommentbeginswith//andincludesallcharactersuntiltheendofthatline.Acommentbeginswith/*andincludesallcharactersthroughthenextoccurrenceofthecharactersequence*/.2.6.2ExtendthelexicalanalyzerinSection2.6.5torecognizetherelationaloperators.2.6.3ExtendthelexicalanalyzerinSection2.6.5torecognizefloat­ingpointnumberssuchas2.,3.14,and.5.AnswerSourcecode:commit8dd1a9aCodesnippet(src/lexer/Lexer.java):publicTokenscan()throwsIOException,SyntaxException{for(;;peek=(char)stream.read()){if(peek==''||peek=='\t'){continue;}elseif(peek=='\n'){line=line+1;}else{break;}}//handlecommentif(peek=='/'){peek=(char)stream.read();if(peek=='/'){//singlelinecommentfor(;;peek=(char)stream.read()){if(peek=='\n'){break;}}}elseif(peek=='*'){//blockcommentcharprevPeek='';for(;;prevPeek=peek,peek=(char)stream.read()){if(prevPeek=='*'&&peek=='/'){break;}}}else{thrownewSyntaxException();}}//handlerelationsignif("".indexOf(peek)>-1){StringBufferb=newStringBuffer();b.append(peek);peek=(char)stream.read();if(peek=='='){b.append(peek);}returnnewRel(b.toString());}//handlenumber,notypesensitiveif(Character.isDigit(peek)||peek=='.'){BooleanisDotExist=false;StringBufferb=newStringBuffer();do{if(peek=='.'){isDotExist=true;}b.append(peek);peek=(char)stream.read();}while(isDotExist==true?Character.isDigit(peek):Character.isDigit(peek)||peek=='.');returnnewNum(newFloat(b.toString()));}//handlewordif(Character.isLetter(peek)){StringBufferb=newStringBuffer();do{b.append(peek);peek=(char)stream.read();}while(Character.isLetterOrDigit(peek));Strings=b.toString();Wordw=words.get(s);if(w==null){w=newWord(Tag.ID,s);words.put(s,w);}returnw;}Tokent=newToken(peek);peek='';returnt;}ExercisesforSection2.82.8.1For-statementsinCandJavahavetheform:for(exprl;expr2;expr3)stmtThefirstexpressionisexecutedbeforetheloop;itistypicallyusedforinitializ­ingtheloopindex.Thesecondexpressionisatestmadebeforeeachiterationoftheloop;theloopisexitediftheexpressionbecomesO.Theloopitselfcanbethoughtofasthestatement{stmtexpr3;}.Thethirdexpressionisexecutedattheendofeachiteration;itistypicallyusedtoincrementtheloopindex.Themeaningofthefor-statementissimilartoexpr1;while(expr2){stmtexpr3;}DefineaclassForforfor-statements,similartoclassIfinFig.2.43.AnswerclassForextendsStmt{ExprE1;ExprE2;ExprE3;StmtS;publicFor(Exprexpr1,Exprexpr2,Exprexpr3,Stmtstmt){E1=expr1;E2=expr2;E3=expr3;S=stmt;}publicvoidgen(){E1.gen();Labelstart=newLable();Lalelend=newLable();emit("ifFalse"+E2.rvalue().toString()+"goto"+end);S.gen();E3.gen();emit("goto"+start);emit(end+":")}}2.8.2TheprogramminglanguageCdoesnothaveabooleantype.ShowhowaCcompilermighttranslateanif-statementintothree-addresscode.AnswerReplaceemit("isFalse"+E.rvalue().toString()+"goto"+after);withemit("ifNotEqual"+E.rvalue().toString()+"0goto"+after);oremit("isNotEqualZero"+E.rvalue().toString()+"goto"+after);
2025/11/27 8:37:48 658KB 龙书答案 完整性高
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一种新型的LDPC译码器设计,钟贵锋,李庆,摘要:性能逼近Shannon限的低密度奇偶校验(Low-DensityParity-Check,LDPC)纠错码,在实际应用中需要解决的问题是尽可能降低译码的复杂度。
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2025/10/25 6:41:45 289KB LDPC
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物联网作为战略性新兴产业的重要组成部分,已成为当前世界新一轮经济和科技发展的战略制高点之一。
物联网通信技术有很多种,从传输距离上区分,可以分为两类:一类是短距离通信技术,代表技术有Zigbee、Wi-Fi、Bluetooth、Z-wave等;
一类是广域网通信技术,业界一般定义为LPWAN(Low-PowerWide-AreaNetwork,低功耗广域网),典型的应用场景如智能抄表。
LPWAN技术又可分为两类:一类是工作在非授权频段的技术,如Lora、Sigfox等,这类技术大多是非标准化、自定义实现;
一类是工作在授权频段的技术,如GSM、CDMA、WCDMA等较成熟的2G/3G蜂窝通信技术,以
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TinyMLMachineLearningwithTensorFlowLiteonArduinoandUltra-Low-PowerMicrocontrollersbyPeteWarden,DanielSitunayakeDeeplearningnetworksaregettingsmaller.Muchsmaller.TheGoogleAssistantteamcandetectwordswithamodeljust14kilobytesinsize—smallenoughtorunonamicrocontroller.Withthispracticalbookyou’llenterthefieldofTinyML,wheredeeplearningandembeddedsystemscombinetomakeastoundingthingspossiblewithtinydevices.PeteWardenandDanielSitunayakeexplainhowyoucantrainmodelssmallenoughtofitintoanyenvironment.Idealforsoftwareandhardwaredeveloperswhowanttobuildembeddedsystemsusingmachinelearning,thisguidewalksyouthroughcreatingaseriesofTinyMLprojects,step-by-step.Nomachinelearningormicrocontrollerexperienceisnecessary.*Buildaspeechrecognizer,acamerathatdetectspeople,andamagicwandthatrespondstogestures*WorkwithArduinoandultra-low-powermicrocontrollers
2025/9/3 4:09:41 23.43MB TinyML Arduino machinelearning Tensorflow
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Single-ModeFiberwithUltra-Low-LossandLarge-Effective-Area.
2025/7/23 22:21:04 440KB 光通信
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USBTraceisaneasytouseandpowerfulUSBanalyzer.USBTracecanmonitorUSBtrafficathostcontrollers,hubsanddevices.Thisisa100%softwareproduct.USBTracesupportsWindows2000,XP,2003/2008Server,Vista,Windows7andWindows8BetaoperatingsystemsandworkswithUSB1.x,2.0and3.0(low,full,high&superspeed)hostcontrollers,hubsanddevices.官方网站:http://www.sysnucleus.com/此版为64位版本,如果您的操作系统是32位的,请在我上传的资源中寻找32位版本的
2025/4/30 7:45:31 5.54MB UsbTrace 破解版
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1.参考文献格式以哈尔滨工程大学毕业论文为基础,因为本校特码不是国标那种类型的!艹2.具体事例参考图片3.支持作者大小写混写(反正自动纠正为首字母大写),中文不做改变4.支持题目大小写混输入,可选择题目改变类型5.目前支持四种格式,期刊,论文,书籍,会议,以后可根据情况再加入6.支持起始页尾添加'P'或者'页',其实都是支持字符串输入的6.若不选择格式类型,题目类型,默认为期刊,题目不做改变7.此为beta版本,若有建议请联系MrLevo@outlook.com或15645183037@163.com8.如果想定制自己学校的参考文献生成器,请将word格式的四种论文格式模板发送至7的邮箱。
9.最后,此软件完全免费,绿色,大小为7.12MB,请勿用于商业用途(虽然很low但是这是定制版本,和cnki这类不一样,btw,cnki那个160+mb还要钱!)havefun!----2016.7.9更新1.增加对输入文献的多选复制2.增加对长文献的拖拽查看
2025/4/23 1:41:13 7.07MB 参考文献 python
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SummaryElasticsearchinActionteachesyouhowtobuildscalablesearchapplicationsusingElasticsearch.You'llrampupfast,withaninformativeoverviewandanengagingintroductoryexample.Withinthefirstfewchapters,you'llpickupthecoreconceptsyouneedtoimplementbasicsearchesandefficientindexing.Withthefundamentalswellinhand,you'llgoontogainanorganizedviewofhowtooptimizeyourdesign.Perfectfordevelopersandadministratorsbuildingandmanagingsearch-orientedapplications.PurchaseoftheprintbookincludesafreeeBookinPDF,Kindle,andePubformatsfromManningPublications.AbouttheTechnologyModernsearchseemslikemagic—youtypeafewwordsandthesearchengineappearstoknowwhatyouwant.WiththeElasticsearchreal-timesearchandanalyticsengine,youcangiveyourusersthismagicalexperiencewithouthavingtodocomplexlow-levelprogrammingorunderstandadvanceddatasciencealgorithms.Youjustinstallit,tweakit,andgetonwithyourwork.AbouttheBookElasticsearchinActionteachesyouhowtowriteapplicationsthatdeliverprofessionalqualitysearch.Asyouread,you'lllearntoaddbasicsearchfeaturestoanyapplication,enhancesearchresultswithpredictiveanalysisandrelevancyranking,andusesaveddatafrompriorsearchestogiveusersacustomexperience.ThispracticalbookfocusesonElasticsearch'sRESTAPIviaHTTP.CodesnippetsarewrittenmostlyinbashusingcURL,sothey'reeasilytranslatabletootherlanguages.What'sInsideWhatisagreatsearchapplication?BuildingscalablesearchsolutionsUsingElasticsearchwithanylanguageConfigurationandtuningAbouttheReaderFordevelopersandadministratorsbuildingandmanagingsearch-orientedapplications.AbouttheAuthorsRaduGheorgheisasearchconsultantandsoftwareengineer.MatthewLeeHinmandevelopshighlyavailable,cloud-basedsystems.RoyRussoisaspecialistinpredictiveanalytics.
2025/3/20 20:13:13 14.44MB Elastic search in Action
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STM32F429DISCO是一款基于STM32F4系列高性能微控制器的开发板,广泛用于嵌入式系统开发。
在这个特定的例子中,我们关注的是如何在该平台上实现RNDIS(RemoteNetworkDriverInterfaceSpecification)功能,利用LWIP(LightweightIP)网络库,并且不依赖DHCP(DynamicHostConfigurationProtocol)服务。
RNDIS是一种由Microsoft定义的接口标准,允许设备以网络适配器的形式与主机通信。
在STM32F429DISCO上实现RNDIS,可以将开发板通过USB连接模拟为一个网络设备,使它能够与主机进行数据交换,如发送和接收TCP/IP协议栈的数据包。
LWIP是一个开源、轻量级的TCP/IP协议栈,适合资源有限的嵌入式设备。
在这个例子中,LWIP将作为STM32F429DISCO的网络堆栈,处理TCP/IP协议,包括IP、TCP、UDP、ICMP等,而无需完整的操作系统支持。
DHCP是用于自动分配网络设备IP地址的协议。
不过,在这个例子中提到“nodhcp”,意味着系统不会使用DHCP服务来动态获取IP地址。
这意味着开发者可能需要手动配置STM32F429DISCO的IP地址,以及其他网络参数如子网掩码和默认网关。
在提供的压缩包文件中,我们可以找到以下几个关键目录:1.**Src**:包含了项目的源代码,这通常包括了RNDIS驱动、LWIP的配置和应用层的代码,以及USB驱动的实现,以便STM32F429DISCO能够作为一个RNDIS设备。
2.**Middlewares**:中间件目录,可能包含LWIP的源代码或者配置文件,以及可能的USB堆栈和其他必要的软件组件。
3.**Drivers**:驱动程序目录,通常会包含STM32F429的HAL(HardwareAbstractionLayer)库和LL(Low-Layer)库,这些库提供了对微控制器硬件功能的访问,包括USB控制器和以太网接口。
4.**MDK-ARM**:这是基于ARM的MicrocontrollerDevelopmentKit,包含了项目工程文件,如`.sln`或`.uvprojx`,以及编译所需的设置和配置。
5.**Inc**:头文件目录,包含了所有源代码中引用的头文件,包括STM32的外设驱动接口声明、LWIP的API定义以及其他必要的数据结构和常量。
在实际开发过程中,开发者需要理解RNDIS的工作原理,熟悉LWIP的配置和使用,掌握STM32F4系列的USB和网络接口编程。
同时,还需要对MDK-ARM集成开发环境有一定的了解,以便于编译、调试和优化代码。
此外,手动配置IP地址可能会涉及到网络规划和静态IP的设置。
这个项目对于想要学习如何在嵌入式系统中实现USB通信和网络功能的开发者来说,是一个很好的实践案例。
2025/3/15 14:50:32 2.64MB lwip
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在日常工作中,钉钉打卡成了我生活中不可或缺的一部分。然而,有时候这个看似简单的任务却给我带来了不少烦恼。 每天早晚,我总是得牢记打开钉钉应用,点击"工作台",再找到"考勤打卡"进行签到。有时候因为工作忙碌,会忘记打卡,导致考勤异常,影响当月的工作评价。而且,由于我使用的是苹果手机,有时候系统更新后,钉钉的某些功能会出现异常,使得打卡变得更加麻烦。 另外,我的家人使用的是安卓手机,他们也经常抱怨钉钉打卡的繁琐。尤其是对于那些不太熟悉手机操作的长辈来说,每次打卡都是一次挑战。他们总是担心自己会操作失误,导致打卡失败。 为了解决这些烦恼,我开始思考是否可以通过编写一个全自动化脚本来实现钉钉打卡。经过一段时间的摸索和学习,我终于成功编写出了一个适用于苹果和安卓系统的钉钉打卡脚本。
2024-04-09 15:03 15KB 钉钉 钉钉打卡