c語(yǔ)言語(yǔ)法分析器

1、精選優(yōu)質(zhì)文檔-傾情為你奉上#include<stdlib.h>#include<stdio.h>#include<string.h>/*/int count=0; /*分解的產(chǎn)生式的個(gè)數(shù)*/int number; /*所有終結(jié)符和非終結(jié)符的總數(shù)*/char start; /*開(kāi)始符號(hào)*/char termin50; /*終結(jié)符號(hào)*/char non_ter50; /*非終結(jié)符號(hào)*/char v50; /*所有符號(hào)*/char left50; /*左部*/char right5050; /*右部*/char first5050,follow5050; /*各產(chǎn)

2、生式右部的FIRST和左部的FOLLOW集合*/char first15050; /*所有單個(gè)符號(hào)的FIRST集合*/char select5050; /*各單個(gè)產(chǎn)生式的SELECT集合*/char f50,F50; /*記錄各符號(hào)的FIRST和FOLLOW是否已求過(guò)*/char empty20; /*記錄可直接推出的符號(hào)*/char TEMP50; /*求FOLLOW時(shí)存放某一符號(hào)串的FIRST集合*/int validity=1; /*表示輸入文法是否有效*/int ll=1; /*表示輸入文法是否為L(zhǎng)L(1)文法*/int M2020; /*分析表*/char choose; /*用戶輸

3、入時(shí)使用*/char empt20; /*求_emp()時(shí)使用*/char fo20; /*求FOLLOW集合時(shí)使用*/*判斷一個(gè)字符是否在指定字符串中*/int in(char c,char *p)int i;if(strlen(p)=0)return(0);for(i=0;i+) if(pi=c) return(1); /*若在，返回1*/if(i=strlen(p) return(0); /*若不在，返回0*/*得到一個(gè)不是非終結(jié)符的符號(hào)*/char c()char c='A' while(in(c,non_ter)=1)c+;return(c);/*分解含有左遞歸的產(chǎn)生

4、式*/void recur(char *point) /*完整的產(chǎn)生式在point中*/ int j,m=0,n=3,k;char temp20,ch;ch=c(); /*得到一個(gè)非終結(jié)符*/k=strlen(non_ter);non_terk=ch;non_terk+1='0'for(j=0;j<=strlen(point)-1;j+) if(pointn=point0) /*如果'|'后的首符號(hào)和左部相同*/ for(j=n+1;j<=strlen(point)-1;j+) while(pointj!='|'&&p

5、ointj!='0') tempm+=pointj+; leftcount=ch; memcpy(rightcount,temp,m); rightcountm=ch; rightcountm+1='0' m=0; count+; if(pointj='|') n=j+1; break; else /*如果'|'后的首符號(hào)和左部不同*/ leftcount=ch; rightcount0='' rightcount1='0' count+; for(j=n;j<=strlen(point)-1

6、;j+) if(pointj!='|') tempm+=pointj; else leftcount=point0; memcpy(rightcount,temp,m); rightcountm=ch; rightcountm+1='0' printf(" count=%d ",count); m=0; count+; leftcount=point0; memcpy(rightcount,temp,m); rightcountm=ch; rightcountm+1='0' count+; m=0;/*分解不含有左遞歸的產(chǎn)生式

7、*/void non_re(char *point) int m=0,j;char temp20;for(j=3;j<=strlen(point)-1;j+) if(pointj!='|') tempm+=pointj;else leftcount=point0; memcpy(rightcount,temp,m); rightcountm='0' m=0; count+; leftcount=point0; memcpy(rightcount,temp,m); rightcountm='0' count+;m=0;/*讀入一個(gè)文法*/ch

8、ar grammer(char *t,char *n,char *left,char right5050)char vn50,vt50;char s;char p5050;int i,j,k;printf("請(qǐng)輸入文法的非終結(jié)符號(hào)串："); scanf("%s",vn);getchar(); i=strlen(vn); memcpy(n,vn,i);ni='0'printf("請(qǐng)輸入文法的終結(jié)符號(hào)串："); scanf("%s",vt);getchar(); i=strlen(vt); memcpy

9、(t,vt,i);ti='0' printf("請(qǐng)輸入文法的開(kāi)始符號(hào)：");scanf("%c",&s);getchar();printf("請(qǐng)輸入文法產(chǎn)生式的條數(shù)："); scanf("%d",&i);getchar(); for(j=1;j<=i;j+)printf("請(qǐng)輸入文法的第%d條（共%d條）產(chǎn)生式：",j,i);scanf("%s",pj-1); getchar(); for(j=0;j<=i-1;j+)if(pj1!

10、='-'|pj2!='>') printf("ninput error!"); validity=0; return('0'); /*檢測(cè)輸入錯(cuò)誤*/ for(k=0;k<=i-1;k+) /*分解輸入的各產(chǎn)生式*/ if(pk3=pk0) recur(pk);else non_re(pk);return(s);/*將單個(gè)符號(hào)或符號(hào)串并入另一符號(hào)串*/void merge(char *d,char *s,int type) /*d是目標(biāo)符號(hào)串，s是源串，type1，源串中的' '一并并入目串； ty

11、pe2，源串中的' '不并入目串*/ int i,j;for(i=0;i<=strlen(s)-1;i+) if(type=2&&si='') ;else for(j=0;j+) if(j<strlen(d)&&si=dj) break; if(j=strlen(d) dj=si; dj+1='0' break; /*求所有能直接推出的符號(hào)*/void emp(char c) /*即求所有由' '推出的符號(hào)*/char temp10;int i;for(i=0;i<=count-1

12、;i+)if(righti0=c&&strlen(righti)=1) temp0=lefti; temp1='0' merge(empty,temp,1); emp(lefti);/*求某一符號(hào)能否推出' '*/int _emp(char c) /*若能推出，返回1；否則，返回0*/int i,j,k,result=1,mark=0;char temp20;temp0=c;temp1='0'merge(empt,temp,1);if(in(c,empty)=1)return(1);for(i=0;i+)if(i=count) r

13、eturn(0);if(lefti=c) /*找一個(gè)左部為c的產(chǎn)生式*/ j=strlen(righti); /*j為右部的長(zhǎng)度*/ if(j=1&&in(righti0,empty)=1) return(1); else if(j=1&&in(righti0,termin)=1) return(0); else for(k=0;k<=j-1;k+) if(in(rightik,empt)=1) mark=1; if(mark=1) continue; else for(k=0;k<=j-1;k+) result*=_emp(rightik); te

14、mp0=rightik; temp1='0' merge(empt,temp,1); if(result=0&&i<count) continue; else if(result=1&&i<count) return(1);/*判斷讀入的文法是否正確*/int judge() int i,j;for(i=0;i<=count-1;i+)if(in(lefti,non_ter)=0) /*若左部不在非終結(jié)符中，報(bào)錯(cuò)*/ printf("nerror1!"); validity=0; return(0);for(

15、j=0;j<=strlen(righti)-1;j+) if(in(rightij,non_ter)=0&&in(rightij,termin)=0&&rightij!='') /*若右部某一符號(hào)不在非終結(jié)符、終結(jié)符中且不為' '，報(bào)錯(cuò)*/ printf("nerror2!"); validity=0; return(0); return(1);/*求單個(gè)符號(hào)的FIRST*/void first2(int i) /*i為符號(hào)在所有輸入符號(hào)中的序號(hào)*/ char c,temp20;int j,k,m;c=v

16、i;char ch=''emp(ch);if(in(c,termin)=1) /*若為終結(jié)符*/ first1i0=c; first1i1='0' else if(in(c,non_ter)=1) /*若為非終結(jié)符*/for(j=0;j<=count-1;j+) if(leftj=c) if(in(rightj0,termin)=1|rightj0='') temp0=rightj0; temp1='0' merge(first1i,temp,1); else if(in(rightj0,non_ter)=1) if(rig

17、htj0=c) continue; for(k=0;k+) if(vk=rightj0) break; if(fk='0') first2(k); fk='1' merge(first1i,first1k,2); for(k=0;k<=strlen(rightj)-1;k+) empt0='0' if(_emp(rightjk)=1&&k<strlen(rightj)-1) for(m=0;m+) if(vm=rightjk+1) break; if(fm='0') first2(m); fm='

18、;1' merge(first1i,first1m,2); else if(_emp(rightjk)=1&&k=strlen(rightj)-1) temp0='' temp1='0' merge(first1i,temp,1); else break; fi='1'/*求各產(chǎn)生式右部的FIRST*/void FIRST(int i,char *p)int length;int j,k,m;char temp20;length=strlen(p);if(length=1) /*如果右部為單個(gè)符號(hào)*/if(p0='

19、') if(i>=0) firsti0='' firsti1='0' else TEMP0='' TEMP1='0' else for(j=0;j+) if(vj=p0) break; if(i>=0) memcpy(firsti,first1j,strlen(first1j); firstistrlen(first1j)='0' else memcpy(TEMP,first1j,strlen(first1j); TEMPstrlen(first1j)='0' else /*如果

20、右部為符號(hào)串*/for(j=0;j+) if(vj=p0) break;if(i>=0) merge(firsti,first1j,2);else merge(TEMP,first1j,2);for(k=0;k<=length-1;k+) empt0='0' if(_emp(pk)=1&&k<length-1) for(m=0;m+) if(vm=rightik+1) break; if(i>=0) merge(firsti,first1m,2); else merge(TEMP,first1m,2); else if(_emp(pk)=

21、1&&k=length-1) temp0='' temp1='0' if(i>=0) merge(firsti,temp,1); else merge(TEMP,temp,1); else if(_emp(pk)=0) break;/*求各產(chǎn)生式左部的FOLLOW*/void FOLLOW(int i)int j,k,m,n,result=1;char c,temp20;c=non_teri; /*c為待求的非終結(jié)符*/temp0=c;temp1='0'merge(fo,temp,1);if(c=start) /*若為開(kāi)始符

22、號(hào)*/temp0='#'temp1='0'merge(followi,temp,1); for(j=0;j<=count-1;j+)if(in(c,rightj)=1) /*找一個(gè)右部含有c的產(chǎn)生式*/ for(k=0;k+) if(rightjk=c) break; /*k為c在該產(chǎn)生式右部的序號(hào)*/ for(m=0;m+) if(vm=leftj) break; /*m為產(chǎn)生式左部非終結(jié)符在所有符號(hào)中的序號(hào)*/ if(k=strlen(rightj)-1) /*如果c在產(chǎn)生式右部的最后*/ if(in(vm,fo)=1) merge(followi,f

23、ollowm,1); continue; if(Fm='0') FOLLOW(m); Fm='1' merge(followi,followm,1); else /*如果c不在產(chǎn)生式右部的最后*/ for(n=k+1;n<=strlen(rightj)-1;n+) empt0='0' result*=_emp(rightjn); if(result=1) /*如果右部c后面的符號(hào)串能推出*/ if(in(vm,fo)=1) /*避免循環(huán)遞歸*/ merge(followi,followm,1); continue; if(Fm='0

24、') FOLLOW(m); Fm='1' merge(followi,followm,1); for(n=k+1;n<=strlen(rightj)-1;n+) tempn-k-1=rightjn; tempstrlen(rightj)-k-1='0' FIRST(-1,temp); merge(followi,TEMP,2); Fi='1'/*判斷讀入文法是否為一個(gè)LL(1)文法*/int ll1() int i,j,length,result=1;char temp50;for(j=0;j<=49;j+) /*初始化*/f

25、irstj0='0' followj0='0'first1j0='0'selectj0='0'TEMPj='0'tempj='0'fj='0'Fj='0'for(j=0;j<=strlen(v)-1;j+) first2(j); /*求單個(gè)符號(hào)的FIRST集合*/printf("n各非終結(jié)符導(dǎo)出的first集:");for(j=0;j<=strlen(v)-1;j+)printf("%c:%s ",vj,first1

26、j); printf("n能導(dǎo)空的非終結(jié)符集合:%s",empty);/ printf("n_emp:");/for(j=0;j<=strlen(v)-1;j+) / printf("%d ",_emp(vj);for(i=0;i<=count-1;i+) FIRST(i,righti); /*求FIRST*/for(j=0;j<=strlen(non_ter)-1;j+) /*求FOLLOW*/if(foj=0) fo0='0' FOLLOW(j); /printf("nfirst:&qu

27、ot;);/for(i=0;i<=count-1;i+) / printf("%s ",firsti);printf("nfollow集合:"); for(i=0;i<=strlen(non_ter)-1;i+) printf("%s ",followi);for(i=0;i<=count-1;i+) /*求每一產(chǎn)生式的SELECT集合*/ memcpy(selecti,firsti,strlen(firsti); selectistrlen(firsti)='0'for(j=0;j<=strl

28、en(righti)-1;j+) result*=_emp(rightij);if(strlen(righti)=1&&righti0='') result=1;if(result=1) for(j=0;j+) if(vj=lefti) break; merge(selecti,followj,1);printf("nselect集合順序是:");for(i=0;i<=count-1;i+) printf("%s ",selecti);memcpy(temp,select0,strlen(select0);temps

29、trlen(select0)='0'for(i=1;i<=count-1;i+) /*判斷輸入文法是否為L(zhǎng)L(1)文法*/ length=strlen(temp);if(lefti=lefti-1) merge(temp,selecti,1); if(strlen(temp)<length+strlen(selecti) return(0);else temp0='0' memcpy(temp,selecti,strlen(selecti); tempstrlen(selecti)='0'return(1);/*構(gòu)造分析表M*/voi

30、d MM() int i,j,k,m;for(i=0;i<=19;i+)for(j=0;j<=19;j+) Mij=-1; i=strlen(termin); termini='#' /*將#加入終結(jié)符數(shù)組*/ termini+1='0'for(i=0;i<=count-1;i+) for(m=0;m+) if(non_term=lefti) break; /*m為產(chǎn)生式左部非終結(jié)符的序號(hào)*/for(j=0;j<=strlen(selecti)-1;j+) if(in(selectij,termin)=1) for(k=0;k+) if(

31、termink=selectij) break; /*k為產(chǎn)生式右部終結(jié)符的序號(hào)*/ Mmk=i;/*判斷符號(hào)串是否是該文法的句型*/void syntax()int i,j,k,m,n,p,q; char ch;char S50,str50; printf("請(qǐng)輸入該文法的句型：");scanf("%s",str);getchar();i=strlen(str);stri='#'stri+1='0'S0='#'S1=start;S2='0'j=0;ch=strj; while(1)if(i

32、n(Sstrlen(S)-1,termin)=1) if(Sstrlen(S)-1!=ch) printf("該符號(hào)串不是文法的句型！"); return; else if(Sstrlen(S)-1='#') printf("該符號(hào)串是文法的句型."); return; else Sstrlen(S)-1='0' j+; ch=strj; else for(i=0;i+) if(non_teri=Sstrlen(S)-1) break; for(k=0;k+) if(termink=ch) break; if(k=strl

33、en(termin) printf("詞法錯(cuò)誤！"); return; if(Mik=-1) printf("語(yǔ)法錯(cuò)誤！"); return; else m=Mik; if(rightm0='') Sstrlen(S)-1='0' else p=strlen(S)-1; q=p; for(n=strlen(rightm)-1;n>=0;n-) Sp+=rightmn; Sq+strlen(rightm)='0' printf("S:%s str:",S);for(p=j;p<=s