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1、实 验 报 告 学号： 姓名： 专业：计算机科学与技术 班级：2班 第9周 课程名称 编译原理课程设计 实验课时8实验项目手工构造Tiny语言的词法分析器实验时间7-10周实验目的 熟悉Tiny语言词法；构造DFA；设计数据类型、数据结构；用C+实现Tiny语言的词法分析器实验环境 Windows 10 专业版 Microsoft Visual Studio 2013实验内容（算法、程序、步骤和方法） 一、Tiny语言记号Reserved wordsSpecial SymbolsOtherif+number(1 or more digits)then-else*endrepeat=until/
2、identifier(1 or more letters)read(write);:=二、构造Tiny语言DFAID：letter(letter)*Number: digit(digit)*三、根据DFA编写词法分析器#include#include#includeusing namespace std;static int rowCounter = 1;/静态变量，用于存储行数static bool bracketExist = false;/判断注释存在与否，false为不存在class Lexpublic:ofstream output;string line = ;Lex(string
3、 inputLine)line = inputLine;scan(Trim(line);rowCounter+;string Trim(string &str)/函数用于去除每行前后空格int s = str.find_first_not_of( t);int e = str.find_last_not_of( t);str = str.substr(s, e - s + 1);str += 0;return str;void scan(string inputLine)ofstream output;output.open(SampleOutput.txt, ios:app);string
4、line = inputLine;int i = 0;string str = ;int temp;string token = ;output rowCounter : line endl;/输出每行while (linei != 0)/根据DFA扫描并判断if (linei = )/注释bracketExist = true;if (bracketExist = true)output t rowCounter : ;while (linei != )output linei;/不处理，直接输出if (linei + 1 != NULL)i+;elsebreak;if (linei = )
5、/注释结束output lineiendl;bracketExist = false;if (bracketExist = false)/数字while (isdigit(linei)temp = temp * 10 + linei;if (!isdigit(linei + 1)output t rowCounter : NUM, val= temp - 0 = a&linei = A&linei = a&linei + 1 = A&linei + 1 = Z) | linei + 1 = | linei + 1 = | linei + 1 = | linei + 1 = NULL)if (i
6、sToken(token)output t rowCounter : token endl;elseint j = 0;while (tokenj != 0)output t rowCounter : tokenj = a&linei = A&linei = a&linei + 1 = A&linei + 1 = Z)if (isResearvedWord(str) /判断是否是保留字output t rowCounter : Reversed Word: str endl;break;elseoutput t rowCounter : ID, name= str endl;break;if
7、(linei + 1 != NULL)i+;str = ;if (linei + 1 != NULL)i+;elsebreak;if (linei + 1 = NULL)if (linei = ;)output t rowCounter : linei;break;/清空，以备下一行读取line = ;str = ;temp = 0;token = ;output endl;output.close();bool isResearvedWord(string s)/存储保留字，并判断string reservedWord8 = if, then, else, end, repeat, unti
8、l, read, write ;bool judge = false;for (int i = 0; i 8; i+)if (s = reservedWordi)judge = true;break;return judge;bool isToken(string s)/存储符号，并判断string token10 = +, -, *, /, =, , (, ), ;, := ;bool judge = false;for (int i = 0; i 10; i+)if (s = tokeni)judge = true;break;return judge;int main()ifstream
9、 input;input.open(SampleInput.tny);string line50;int i = 0;while (getline(input, linei)/cout linei endl;i+;input.close();cout endl endl Reading source file completed! endl;int j = 0;remove(SampleOutput.txt);for (j = 0; j i; j+)Lex lex(linej);cout endl endl Writing file completed! endl endl endl;retur
