編譯原理語法分析實驗

1、編譯原理程序設計實驗報告表達式語法分析器的設計實現(xiàn) 班級：計算機1306班 姓名：李佳澤 學號：20133951 實驗目標：實現(xiàn)表達式語法分析器的設計實現(xiàn)，使用遞歸下降子程序、ll1分析法、lr分析法，判斷一個表達式是否符合某個語法。 實驗內(nèi)容：算數(shù)表達式的變換文法：e -> t e1 i. (w0 t e1 u)0 e )#)t -> f t1 (l (|t1> 31 f t1 |(1wo0)1()#iet-ti® jf二" ll(1)分析表：f t i | (e)(流程圖:逆序壓棧數(shù)據(jù)結(jié)構(gòu)：struct nodechar conten七30; int

2、七 ype;node * next;建立鏈表用于標識符rr，常數(shù)ct ,字符存ct ,字符串st , token源程序代碼:1 遞歸調(diào)用子程序#inc lude<iostream># include<string.h># include<fstream>#include<stdlib.h>#include <stack> using namespace std;#define notkey 50 #define 汀 00#define ctol#define st 02 #define ct 03 char * kt5=”inttma

3、intvoidtifvchar;char*pt18斗”>=”,n<=h； int ty =3;int dd=o;char vn=,e,；e,t；t,；f;charvt=,ivww；c；)#;char * right二'te“,“wte“,”,“ft“,“wfu,“”,”i“,”(e)“;int seekkt(char * token)for(int i=0; i<5; i+)if(strcmp(token,kti) = 0)return i+4;return notkey;int seekpt(char * token)for(int i=0; i<18; i+

4、) if(strcmp(token,pti) = 0) return i+10;return -1;int main()int tohn();int intn ();int sean();int right();int print();tohn();intn ();scan();if(dd=o)cout«endl;cout«"分析結(jié)果：” «endl;cout«endl;right();print();return 0;stack <char> s;struct nodechar content30; int type;node *

5、 next;node * ithead;node * cthead;node * cthead;node * sthead;node * tohead:node * pp;void e();void t();void f();void tohn()tohead = new node(); strcpy(tohead->content,hn);tohead->type = 0;tohead->next = null;void setton(char * content,int type)node * p = tohead ;node * temp = new node(); w

6、hile(p->next !=null)p = p->next;strcpy(temp> content,content); temp->type = type;temp-> next = null;p->next = temp;初始化所有表頭結(jié)點void intn()ithead = new node(); strcpy(ithead->content/,u); ithead->type = it; ithead->next = null;sthead = new node();strcpy(sthead->content,nn);

7、sthead->type = st;sthead->next = null;cthead = new node();strcpy(cthead->content/,n);cthead->type = ct;cthead->next = null;cthead = new node();strcpy(cthead->content/ih);cthead->type = ct; cthead->next = null;創(chuàng)建新節(jié)點void setn(char * contentjnt type,node * head)node * p = head ;

8、node * temp = new node();int flag = 0;while(p->next!=null)if(strcmp(content,p next>content) = 0)flag = 1;p = p->next;if(flag = 0)strcpy(temp->content,content);temp->type = type;temp->next = null;p->next = temp;void print()node * p = tohead;p = p->next; while(p!=null)p = p->

9、;next;void sean()/char filename50j;char ch;char a30;char * token;int i;file * fp;/*printf(h輸入語法分析的c語言程序(形如d:test.txt)： n”); scanf(m%sn,filename);fp = fopen(filename,"rn);*/fp=fopen("test.txt","rm);ch = fgetc(fp);while(ch!-#r)i = 0;以字母或者下劃線開頭，處理關(guān)鍵字或者標識符if(ch>=,a, && ch&

10、lt;=,z,) | (ch>=,a, && ch<=,z,) | ch =)while(ch>='a, && ch<=,z,)|(ch>=,a, && ch<=,z,)|(ch>=,0, && chv=9) | ch =ai+ = ch;ch = fgetc(fp);token = new chari+l;memcpy(token,a,i)；tokeni二 v)：int seektemp = seekkt(token);if(seektemp!=notkey)setton(tok

11、en,seektemp);else setn(tokenjtjthead);setton(token,it);fseek(fp,-1 l,seek_cur);/以數(shù)字開頭，處理數(shù)字else if(ch >='0' && chv二9)int flag = 0;int flag2 = 0;while(ch >='0' && ch<=,9,)ai+ = ch;ch =fgetc(fp);1處理floatif(ch = 7)flag = 1;ai+ = ch;ch = fgetc(fp);if(ch>=,0, &a

12、mp;& chv=9)while(ch>=,0, && ch<=,9,)ai+ = ch;ch = fgetc(fp);處理 doubleif(ch = e | ch = 0)ai+ = ch; ch = fgetc(fp);if(ch =| ch = ai+ = ch; ch = fgetc(fp);if(ch >=,0, && chv=9)ai+ = ch;ch = fgetc(fp);token= new chari+l;memcpy(tokenai)；tokeni二 v)：if(flag = 0)setn(token,ct,ct

13、head);setton(tokemct);elsesetn(token.ct.cthead);setton(token,ct);fseek(fp,-ll,seek_cur);處理常量字符串else if(ch = uh)ai+ = ch;ch = fgetc(fp); while(ch!=hm)ai+ = ch;ch = fgetc(fp);ai+ = ch;ch = fgetc(fp);token = new chari+l;memcpy(token,a,i);tokeni二 vx;setn(token,st,sthead);setton(token.st);fseek(fp,-1 l,s

14、eek_cur);處理常量字符else if(ch = v)ai+ = ch; ch = fgetc(fp);while(ch!=v)ai+ = ch; ch = fgetc(fp);ai+ = ch;ch = fgetc(fp);token = new chari+l j;memcpy(tokenai)；tokeni二 v)：setn(token,ct,cthead);setton(token,ct);fseek(fp<l l,seek_cur);結(jié)朿符elseif(ch>=*! '&&chv 二 7')|(ch> 二丫&&c

15、h<=,)|(ch>=t&&ch<="')|(ch>=,(,&&ch<=-')int seektemp;if(ch=,<,|ch=,>,|ch='=,)ai+ = ch;ch = fgetc(fp);else ai+ = ch;ch = fgetc(fp);)token = new chari+l; memcpy(token,a,i);token i =、0'seektemp=seekpt(token);if(seektemp=-l)/結(jié)束符不存在cout« “結(jié)束符錯

16、誤請檢查”endl;dd=l;1elsesetton(token,seektemp);fseek(fp, 1 l,seek_cur);ch = fgetc(fp);setton(“#“,333);fclose(fp);void right()pp=tohead;pp=pp->next;e()；if(strcmp(pp->content,',#'r) = ()&&ty=3)cout«,right',«endl;elseif(strcmp(pp->content,n#h) != 0 &&ty=3)cout

17、«,wrong,«endl«endl; cout«"理由：括號不匹配"«endl;cout«endl;1else 訐(ty= 1)cout«hwrongm«endl«endl;coutvv”理由：非法字符u«endl;cout«endl;else if(ty =2)cout«hwrong"«endl«endi;cout«h理由：缺少 “)”“endl;cout«endl;void e()if (ty !=

18、3) return;t()；while (strcmp(pp->content,m+n) = o|strcmp(pp->content,-n) = 0)pp=pp next;t();return ;void t()if (ty != 3) return;f()；while (strcmp(pp->content/,*f,) = 0|strcmp(pp->content/7n) = 0)pp=pp->next;f()；return ;void f()訐(ty != 3) return;if (pp->type = ct|pp->type = it)pp=

19、pp->next;return;elseif(strcmp(pp->content/l(h) = 0) pp=pp->next;e()；if (strcmp(pp->content,h),f) = 0)pp=pp > next;return;elsety = 2;return;elsereturn;ty= 1;12.ll1分析法# include<iostream># include<stri ng.h># include<fstream>#include<stdlib.h> #include <stack&g

20、t; using namespace std; #define notkey 50 #define it 00 #define ct 01 #define st 02 #define ct 03 char * kt5=rinttmaintvoidtiftchar"char * pt18=n>=n,<="，”二”; int dd=o;int sss=o;int seekkt(chcir * token)for(int i=0; i<5; i+)if(strcmp(token,kti) = 0)return i+4;return notkey;int seek

21、pt(char * token)for(int i=0; i<18; i+)if(strcmp(token,pti) = 0) return i+10;return -1;int main()inttohn();intintn ();intscan();int print();int wrong();tohn();intn ();scan();print();if(dd=o)cout«"分析結(jié)果：m«endl«endl; wrong();cout«endl;return 0;stack <char*> s;struct nod

22、echar content30j;int type;node * next;node * ithead;node * cthead;node * cthead;node * sthead;node * tohead;node * pp;void tohn()tohead = new node(); strcpy(tohead->content, ” ”);tohead->type = 0;tohead->next = null;void setton(char * content,int type)node * p = tohead ;node * temp = new no

23、de(); while(p->next!=null)p = p->next;strcpy(temp> content,content);temp->type = type;temp->next = null;p->next = temp;初始化所有表頭結(jié)點 void intn()ithead = new node(); s trcpy (i thead->conten t,tht);ithead->type = it; ithead->next = null;sthead = new node();strcpy(sthead->con

24、tent/'n); sthead->type = st; sthead->next = null;cthead = new node();strcpy(cthead->content/h,);cthead->type = ct;cthead->next = null;cthead = new node();strcpy(cthead->content,nn); cthead->type = ct; cthead->next = null;創(chuàng)建新節(jié)點void setn(char * content,int type,node * head)

25、node * p = head ;node * temp = new node();int flag = 0;while(p->next!=null)if(strcnip(content,p->next->conte nt) = 0)flag = 1;p = p->next;)if(flag = 0)strcpy(temp > content,conte nt);temp->type = type;temp-> next = null;p->next = temp;打印鏈表void print()node * p = tohead; p = p-

26、>next; while(p!=null) p = p->n ext;掃描程序void scan()/char filename50;char ch;char array 30; char * token;int i;file * fp;/*printf("輸入語法分析的c語言程序(形如test.txt)： nh); scanf(m%sn,filename);fp = fopen(filename,"rn);*/fp=fopen("test.txt","rm);ch = fgetc(fp);while(ch!二'#'

27、)i = 0;if(ch>='a' && ch<='z,) | (ch>='a* && ch<=rz') | ch =while(ch>='a' && ch<='z')|(ch>=,a, && ch<='z')|(ch>=,0, && ch<='9') | ch =array i+ = ch;ch = fgetc(fp);token = new char

28、fi+1;memcpy(token,array,i);tokeni二'0；int seektemp = seekkt(token);if(seektemp!=notkey)setton(token,seektemp);else setn(token,it,ithead);setton(token,it);fseek(fp,-l l,seek_cur);/以數(shù)字開頭，處理數(shù)字else if(ch >='0' && ch<='9')int flag = 0;int flagl = 0;while(ch >='0

29、9; && ch<=,9,)arrayli+j = ch;ch =fgetc(fp);處理floatif(ch 二二 t)flagl = 1;array fi+ = ch;ch = fgetc(fp);if(ch>=,0, && chv二9)while(ch>='0' && ch<=,9,)arrayi+ = ch;ch = fgetc(fp);處理 doubleif(ch = 'e' | ch = 'e') arrayi+ = ch; ch = fgetc(fp);if(c

30、h =| ch ='')array fi+l = ch; ch = fgetc(fp);if(ch >='0* && ch<=*9') array fi+l = ch; ch = fgetc(fp);token= new chari+1;memcpy(token,arrays)；tokeni = vx;if(flag = 0)setn(token.ct.cthead);setton(token,ct);elsesetn(token,ct,cthead);setton(token,ct); fseek(fp, 1 l,seek_cur)

31、;處理常量字符串else if(ch = nn)arrayi+ = ch;ch = fgetc(fp);while(ch!=um)arrayi+j = ch;ch = fgetc(fp);arrayi+j = ch;ch = fgetc(fp);token = new chari+l;memcpy(token,array,i);tokeni二 vt;setn(token,st,sthead);setton(token,st);fseek(fp,ll,seek_cur); /處理常量字符else if(ch = '")arrayi+ = ch;ch = fgetc(fp);wh

32、ile(ch!二arrayi+j = ch;ch = fgetc(fp);arrayi+ = ch;ch = fgetc(fp); token = new chari+l;memcpy (token .array, i);tokeni = vx;setn(token.ctcthead);setton(token,ct);fseek(fp<l l，seek_cur);結(jié)朿符 elseif(ch>=*! '&&ch<='/,)|(ch>=,: '&&ch<=,)|(ch>=,&&ch<

33、=,v,)|(ch>=,( '&&chv=) inf seektemp;if(ch=,<'|ch=,>,|ch=,=,) arrayi+ = ch; ch = fgetc(fp);) else arrayi+ = ch;ch = fgetc(fp);token = new chari+l; memcpy(token,array,i);tokens =seektemp=seekpt(token); if(seektemp=-1)/結(jié)束符不存在coutvv “結(jié)束符錯誤請檢査 vendl;dd=l;elsesetton(token,seektemp

34、);fseek(fp,-1 l,seek_cur);ch = fgetc(fp);setton(“#“,333);fclose(fp);內(nèi)容類碼(24aa0+16)25*188&23/19-17#123*/void ssss()if(s.top()二二”e”) if(pp->type=it)|(pp->type=ct) s.pop();s.push(“el“)；s.push(,tn);sss=l;return;if(pp->type=24)s.pop();s.push("el");s.push(t);if(slop()=nelu)if(pp->

35、;type= 16)| (pp->type= 17) s.popo;s.push(” el“)；s.push("tm);s.push("wo");sss=l;retum;if(pp->type=25)s.popo;sss=l;return;if(pp->type=333)s.pop();sss=l;return;if(s.top()二二”t“)if(pp->type=it)|(pp->type=ct) s.pop();s.push(”tl");s.pushc'f”)；if(pp->type=24)s.pop();s.push(“tl“)；s.push("f");sss=l;retum; 處理 floatif(s.top()=ntln)if(pp->type= 16)|(pp->type= 17) s.pop();sss=l;return;if(pp->type= 18)|(pp->type= 19) s.pop();s.push(“tl“)；s.push("f");s.push("wl");sss=l;return;if(pp->type=25)s.pop();