编译原理 词法分析+语法分析.doc

编译原理实验学号：姓名： 班级：实验一：文件读入缓冲区，每次单字符输出源码：#include #include #include using namespace std;string ad1,ad2,cache;int curPos;bool getIn()coutad1;ifstream fin(ad1);if(fin.is_open()string str(istreambuf_iterator(fin), istreambuf_iterator();cache.swap(str);fin.close();curPos = 0;return true;return false;char getChar()if(curPos cache.size()return cachecurPos+;else return 0;int main()if(!getIn()return 1;char ch;while(ch = getChar()coutch;实验结果：实验二：词法分析#include #include #include #include #include #include #include #include using namespace std;const int BUFFER_SIZE = 1024;char bufferBUFFER_SIZE;enum Datatype RESERVE_WORD=1,IDENTIFIER=2,DIGIT=3,OPERATOR=4,SEPARATOR=5;/注意后面有分号const string Keyword = main,if,cout,int,return;ifstream inFile;ofstream outFile;int error;char cur,nex,ch;typedef structDatatype type;string value;Mytype;Mytype temp;queueque;inline void InputFile()string inFilename;cout Input the name of SourceFile: inFilename;inFile.open(inFilename.c_str();/string:c_str()返回的是const指针,String类中的一个函数if(!inFile)cout Cannot open the file! endl;system(pause);exit(1);return;inline void OutputFile()string outFilename;cout Input the name of DestinationFile: outFilename;outFile.open(outFilename.c_str();/string:c_str()返回的是const指针,String类中的一个函数if(!outFile)cout Cannot open the file! endl;exit(1);/同时把信息导入到文件中if(error)cout The number of errors: error endl;outFile The number of errors: error endl;while(que.size()temp = que.front();que.pop();outFile ( temp.type , temp.value ) endl;cout ( temp.type , temp.value ) endl;return;bool IsKeyword(string &str)for(int i=0;i5;i+)if(str = Keywordi) return true;return false;/注意有的运算符需要进行超前搜索才能确定bool IsOperator(char ch)if(ch=|ch=+|ch=-|ch=*|ch=/|ch=!) return true;return false;bool IsSeperator(char ch)if(ch=,|ch=;|ch=(|ch=)|ch=|ch=) return true;return false;inline void Acquire_line()/while(inFile.getline(buffer,BUFFER_SIZE,n) cout buffer endl;while(inFile.getline(buffer,BUFFER_SIZE,n)int i=0;for(i;istrlen(buffer);i+)temp.value = 0;/bug:因为定义的temp是全局变量，而temp.value是字符串，所以每次使用都有“清0”ch = bufferi;if(isspace(ch) continue;if(IsOperator(ch)/+,-,*,/,!temp.type = OPERATOR;temp.value += ch;if(i(strlen(buffer)-1)/需要读取下一个字符进行查验nex = buffer+i;if(IsOperator(nex)if(nex=) temp.value +=nex;else if(ch=+&nex=+)|(ch=-&nex=-) temp.value+=nex;else cout error: temp.value endl;if(bufferi!=) -i;que.push(temp);else if(IsSeperator(ch)temp.type = SEPARATOR;temp.value += ch;que.push(temp);else if(isdigit(ch)/一旦查看到的是一个数字，需要继续往后搜索是否有后续的数字。temp.type = DIGIT;temp.value += ch;do/再嵌套一个循环让其找完数nex = buffer+i;if(isdigit(nex) temp.value += nex;while(isdigit(nex)&istrlen(buffer);if(!isdigit(nex) -i;que.push(temp);elseif(isalpha(ch)/是字符temp.value += ch;donex = buffer+i;if(isalpha(nex) temp.value += nex;while(isalpha(nex)&istrlen(buffer);if(!isalpha(nex) -i;/剩下的就是我们定义的字符，需要先判断关键字，然后判断标识符/const string Keyword = main,if,cout,int,return;/*enum Datatype RESERVE_WORD=1,IDENTIFIER=2,DIGIT=3,OPERATOR=4,SEPARATOR=5;/注意后面有分号*/bool flag = true;for(int i=0;i5;i+)if(temp.value=Keywordi)temp.type = RESERVE_WORD;flag = false;que.push(temp);break;if(flag)temp.type = IDENTIFIER;que.push(temp);return ;/*从文件中读入一行：ifstream ff; char llMAXLEN;ff.getline(ll,MAXLEN,n);*/void Initial()error = 0;while(que.size() que.pop();return ;int main()Initial();InputFile();Acquire_line();OutputFile();return 0;实验结果：实验三：自顶向下的语法分析#include #include #include #include #include #include #include #include #include #include using namespace std;const string ID = num,NUM = num,ADD = +,SUB = -,MUL = *,DIV = /,NOTEND = NOTEND,LEFTK=(,RIGHTK = ); const string E = E,E1 = E,T = T,T1 = T,F = F;const string ENDofFILE = $,NOTHING = NULL;class Elementpublic:string name, kind;Element()Element(string a,string b):name(a),kind(b);string cache;int curPos;vector vecWord;void fread()ifstream fin(test.cpp);string tmp(istreambuf_iterator(fin), istreambuf_iterator();tmp.swap(cache);curPos = 0;char getChar()if(curPos cache.size()return cachecurPos+;else return 0;void putBack()curPos-;Element getWord(char a)string str(1,a);while(a = getChar()if(isalpha(a) | isdigit(a) | a = _)str+=a;elseputBack();break;return Element(str,ID);Element getNum(char a)string str(1,a);while(a = getChar()if(isdigit(a)str +=a;elseputBack();break;/=w=return Element(str,NUM);void wordAnalysis()vector v;char ch;while(ch = getChar()if(ch = + |ch = - |ch = * |ch = / |ch = ( |ch = ) )v.push_back(Element(string(1,ch),string(1,ch);else if(isalpha(ch) | ch = _)v.push_back(getWord(ch);else if(isdigit(ch)v.push_back(getNum(ch);v.push_back(Element(ENDofFILE,ENDofFILE);for(int i = 0;iv.size();i+),vi.kindendl;cout=wordAnalysis END=endl;v.swap(vecWord);bool is_syntaxAnalysis_succeed = true;void error(int ip,int k)coutk mistake ocurred at ip T E,E - + T E,E - - T E,E - NULL,T - F T,T - * F T,T - / F T,T - NULL,F - id,F - ( E ),;vector viaString = ,/0T,E1,/1ADD,T,E1,/2SUB,T,E1,/3NOTHING,/4F,T1,/5MUL,F,T1,/6DIV,F,T1,/7NOTHING,/8ID,/9LEFTK,E,RIGHTK,/10;vector testViaString = ,/0Element(T,NOTEND),Element(E1,NOTEND),/1Element(ADD,ADD),Element(T,NOTEND),Element(E1,NOTEND),/2Element(SUB,SUB),Element(T,NOTEND),Element(E1,NOTEND),/3Element(NOTHING,NOTHING),/4Element(F,NOTEND),Element(T1,NOTEND),/5Element(MUL,MUL),Element(F,NOTEND),Element(T1,NOTEND),/6Element(DIV,DIV),Element(F,NOTEND),Element(T1,NOTEND),/7Element(NOTHING,NOTHING),/8Element(ID,ID),/9Element(LEFTK,LEFTK),Element(E,NOTEND),Element(RIGHTK,RIGHTK),/10;mapstring,mapstring,vector mp;mpEID = testViaString1;mpELEFTK= testViaString1;mpE1ADD = testViaString2;mpE1SUB = testViaString3;mpE1RIGHTK = testViaString4;mpE1ENDofFILE = testViaString4;mpTID = testViaString5;mpTLEFTK = testViaString5;mpT1ADD = testViaString8;mpT1SUB = testViaString8;mpT1MUL = testViaString6;mpT1DIV = testViaString7;mpT1RIGHTK = testViaString8;mpT1ENDofFILE = testViaString8;mpFID = testViaString9;mpFLEFTK = testViaString10;int ip = 0;Element tmpX(E,NOTEND);stack stk;stk.push(tmpX);while(stk.empty()=false)tmpX = stk.top();/coutTMPX tmpX.name,tmpX.kindendl;stk.pop();if (tmpX.kind = ENDofFILE);else if(tmpX.kind != NOTEND )if(tmpX.kind = vecWordip.kind)coutmatch(tmpX.name:vecW )endl;ip+;else error(ip,0);break;else if(mp tmpX.name vecWordip.kind .empty() /kind ?error(ip,1);break;else auto &vec = mp tmpX.name vecWordip.kind ;couttmpX.name ;for(int i = 0;ivec.size();i+);cout=0;i-)/coutadd ;if(vec