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1、HIT CSTPDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTFormal LanguageLanguagesAutomataComputationPDF 文件使用 “pdfFactory Pro“ 试用版本创建 虰 HIT CSTComputation2+ 350 0 1 0+ 0 0 1 10 1 0 10 0 1 0 0 0 1 1011PDF 文件使用 “pdfFactory Pro“ 试用版本创建 耀 HIT CSTComputation for computerLanguageAutomaton0011101100001011 11001001111
2、0000111011000010 110010011110011101100001011 11001001111000CodedProcessProduce( formal description )( set of strings )In computerIn our lifePDF 文件使用 “pdfFactory Pro“ 试用版本创建 穜 HIT CSTLanguageSo we haveWhat is a language ?sentence 1, sentence 2, sentence 3, LanguageThis is a sentence.This is also a se
3、ntence.the set of sentencesPDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTLanguageLanguage = sentence | P(sentence) Example :English= Welcome to this class ! ,Its not easy, but you will enjoy it. ,Do your best ! ,Have a good time ! , Informal notationPDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTSentence and Alp
4、habetsentence/string = sequence of symbols chosenfrom the alphabet example : Mouse love rice.alphabet = finite set of symbolsexample : ASCII, =0,1symbols sentences languagePDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTRules/Grammarrules = by which sentence is generatedexample : rules for English | | |PDF
5、文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTNotation of languageexample :L=s|s consists of 0s and 1s, and end with 0 alphabet : 0,1ruleL= 0,00,10,000,010,100,110,0000,11111100L, 1L, 0001L, 20LPDF 文件使用 “pdfFactory Pro“ 试用版本创建 3 HIT CSTNotation of languageAnother example :alphabet = 0,1L= 0n1n| n 1 L= 01, 001
6、1, 000111, 00001111, 0000011111 , PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTString operationsConcatenationw=a1a2an abbav=b1b2bnbbbaaawv=a1a2anb1b2bn abbabbbaaaReversewR=anan-1a1PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTThe empty stringA string with no letters : | = ?w = ? w = ?PDF 文件使用 “pdfFactory Pro“
7、试用版本创建 HIT CSTAnother operationw = abb w2=abbabb, w3=abbabbabbwn= w w wndefinition : w0 = PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTThe * operation*: the set of all possible strings from alphabet = a, b *= ,a,b,aa,ab,ba,bb,aaa,aab,aba,baa, The + operation = a, b += * - = a,b,aa,ab,ba,bb,aaa,aab,aba,ba
8、a, PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTOperations on languages The usual set operationsL1 L2= w | w L1or w L2LR= wR| w LL1 L2= w | w L1and w L2L1- L2= w | w L1and w L2Reverse Example L = anbn| n 1 LR= bnan| n 1PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTOperations on languagesConcatenation L1L2 = wv
9、 | w L1and v L2ExampleL= anbn| n 1 , K = bnan| n 1 LK= anbnbnan| n 1 LK= anbnbmam| n 1 , m 1 L2= ?PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTTopics about Languagegrammar/rules Language is generated according to grammar. Form if ($input = m!(?:19|20)dd)-/.(01- 9|1012)-/.(01- 9|120- 9|301)$!) # At this p
10、oint, $1 holds the year, $2 the month and $3 the day of the date enteredif ($3 = 31 and ($2 = 4 or $2 = 6 or $2 = 9 or $2 = 11) return 0; # 31st of a month with 30 daysPDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTelsif ($3 = 30 and $2 = 2) return 0; # February 30th or 31st elsif ($2 = 2 and $3 = 29 and n
11、ot ($1 % 4 = 0 and ($1 % 100 != 0 or $1 % 400 = 0) return 0; # February 29th outside a leap year else return 1; # Valid date else return 0; # Not a datePDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTDiscussionExercise 2.2.5(a)The set of all strings that each block of five consecutive symbols contains at le
12、ast two 0s .PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTExercise 2.2.5(a)start0000000 11111110101010,1010,10,10,10000010100111001011101110100111001PDF 文件使用 “pdfFactory Pro“ 试用版本创建 HIT CSTExercise010101start0000111100000000111111111001010101012.2.5(a)010,10101010,10,10,1010,1PDF 文件使用 “pdfFactory Pro“ 试用版
13、本创建 HIT CST01010101011001100011010101110110101110000101110111001111101100110001100111011100010000100010110111010110110000000110011001010011011101110011101010100111010101001010101111111101111110100101101110110101111000000000000011111011111001100011001100010001000011000000000011101110101101110010001000010100100100011111011100111011001100
