南航金城学院编译原理课程设计杨阳教的.doc

产生式主程序：Program- main () DefList; StmtList定义变量：DefList- Def; DefListDefList- DefDef- Type IDListType- intType- floatIDList- id, IDListIDList- id定义语句：StmtList- Stmt; StmtListStmtList- Stmt;赋值语句：Stmt- id:=E条件分支语句Stmt- if (BE) StmtList else StmtList算数表达式：(1) 自上而下分析法 (2) 自下而上分析法E- TEE- TE- +TEE- E+TE- T- FT- FTT- T*FT- *FTF- (E)T- F- idF- (E)F- numF- idF- floatnumF- intnumF- floatnum布尔表达式：BE- id id idBE- id = idBE- id id intnumBE- id = intnum课程设计要实现的内容：（1）设计词法分析器设计各单词的状态转换图，并为不同的单词设计种别码。功能包括：a. 能够拼出语言中的各个关键字、运算符和界符；b. 能够识别出标识符和不同类型的常量；c. 能对输入的一段文本程序输出其词法成分的各种别编码和属性值（对关键字，输出其种别编码，属性值为空；对常量，输出其种别编码和常量的值；对变量，输出其种别编码和变量名）。（2）语法分析要求用递归下降分析法、LL(1)分析法或SLR(1)分析法，对词法分析的结果进行语法分析。（实现对标识符表的插入和查找，见（3）若语法正确，则输出一棵语法树。若语法错误，则报错。（3）设计标识符表，并实现一定的语义分析(可选)标识符表应至少包括名字栏和数据类型栏。在语法分析中：对在声明语句中出现的关于标识符的声明，如果该名字在符号表中不存在，则将其加入到符号表中，并将数据类型填入。若名字已经存在被声明过，则报错。对一般语句中出现的标识符，可以查找标识符表，若标识符不在表中，则报错。验收要求1、 有标识符表的构造说明文档（可选）2、 有种别编码表的说明文档3、 有词法分析的DFA图4、 若使用了递归下降分析法需要有根据产生式构造的first/follow集、若使用了LL(1)分析法需要有预测分析表，若使用了SLR(1)分析法需要有SLR（1）分析表5、 有可执行的源程序，能输出词法分析的结果、语法分析的语法树(和标识符表)源程序：#include #includeusing namespace std;#include#include #includeint i,j,k,flag,number,status,m=0,n=0,d,dian;/d为在计算小数时除以0.1的次数/*status which is use to judge the string is keywords or not!*/char ch;float number1;char words10 = ;char program500;int flags500; /存储输入句子string cnt500;/标识符int temp=0; /数组下标int is_right=1; /判断输出信息char num500;/-词法分析-int Scan(char program) char *keywords9 = int,char,float,if,else,do,while,printf,main; /关键字number=0;status=0;j=0;ch=programi+; /遍历while(ch= |ch=n) /跳过空字符（无效输入） ch=programi+; if (ch = a) & (ch = a) & (ch = z ) wordsj+=ch; ch=programi+; i-; wordsj+ = 0;for (k = 0; k = 0) & (ch = 0 ) & (ch =0)&(ch: if (ch = ) wordsj+ = ch; wordsj = 0; ch = programi+; if (ch = =) wordsj+ = ch; wordsj = 0; flag = 403; else i-; flag = 404; break; case: if (ch = )wordsj+ = ch;wordsj = 0;ch = programi+;if (ch = =)wordsj+ = ch;wordsj = 0;flag = 405;elsei-;flag = 406;break;case!:if (ch = !)wordsj+ = ch;wordsj = 0;ch = programi+;if (ch = =)wordsj+ = ch;wordsj = 0;flag = 407;elsei-;flag = 408;break;case+:if (ch = +)wordsj+ = ch;wordsj = 0;ch = programi+;if (ch = =)wordsj+ = ch;wordsj = 0;flag = 409;else if (ch = +)wordsj+ = ch;wordsj = 0;flag = 410;elsei-;flag = 411;break;case-:if (ch = -)wordsj+ = ch;wordsj = 0;ch = programi+;if (ch = =)wordsj+ = ch;wordsj = 0;flag = 412;else if( ch = -)wordsj+ = ch;wordsj = 0;flag = 413;elsei-;flag = 414;break;case*:if (ch = *)wordsj+ = ch;wordsj = 0;ch = programi+;if (ch = =)wordsj+ = ch;wordsj = 0;flag = 415;elsei-;flag = 416;break;case/:if (ch = /)wordsj+ = ch;wordsj = 0;ch = programi+;if (ch = =)wordsj+ = ch;wordsj = 0;flag = 417;elsei-;flag = 418;break;case:wordsj = ch;wordsj+1 = 0;flag = 419;break;case;:wordsj = ch;wordsj+1 = 0;flag = 501;break;case(:wordsj = ch;wordsj+1 = 0;flag = 502;break;case):wordsj = ch;wordsj+1 = 0;flag = 503;break;case:wordsj = ch;wordsj+1 = 0;flag = 504;break;case:wordsj = ch;wordsj+1 = 0;flag = 505;break;case:wordsj = ch;wordsj+1 = 0;flag = 506;break;case:wordsj = ch;wordsj+1 = 0;flag = 507;break;case:wordsj = ch;wordsj+1 = 0;flag = 508;break;case:wordsj = ch;wordsj+1 = 0;flag = 509;break;case%:if (ch = %)wordsj+ = ch;wordsj = 0;ch = programi+;if (ch = =)wordsj+ = ch;wordsj = 0;flag = 510;elsei-;flag = 511;break;case,:wordsj = ch;wordsj+1 = 0;flag = 512;break;case#:wordsj = ch;wordsj+1 = 0;flag = 513;break;case:wordsj = ch;wordsj+1 = 0;flag = 514;break;case :/空格 wordsj =_; wordsj+1 = 0; flag = 515; break;case$:wordsj = #;wordsj+1 = 0;flag = 0;break;default:flag = -1;break;return flag;/-语法分析（递归下降）-void E();void E1();void T();void T1();void F();void E()coutTE endl;T();E1();void E1()if(flagstemp=411) cout+Eendl; temp+; T(); E1();void T()coutFTendl; F();T1();void T1()if(flagstemp=416)cout*Fendl;temp+;F();T1();void F() if(flagstemp=100|flagstemp=200|flagstemp=201) coutcnttempendl; temp+; else if(flagstemp=502) cout(endl; temp+; E(); if(flagstemp=503) cout)endl; temp+; if(flagstemp=0|flagstemp=501) is_right=1; temp+; else is_right=0; else is_right =0;void main() int i=0,num=0; cout请输入测试程序或者表达式，以$结束endl; do ch =getchar(); programi+ = ch; while(ch != $); i = 0; cout词法分析：endl; do flag = Scan(program);/词法分析 if (flag = 200) cout(flag,number)endl;flagsnum=flag;stringstream stream;streamcntnum;stream.clear(); num+; else if(flag=201) for(i=d;i0;i-) number1=number1*0.1; number1=number1+number; cout(flag,number1)endl;flagsnum=flag;stringstream stream;streamcntnum;stream.clear();num+; e