c語(yǔ)言語(yǔ)法分析器(總18頁(yè)

1、#include#include#include/*/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)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*/c

2、har 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(hù)輸入時(shí)使用*/char empt20; /*求_emp()時(shí)使用*/char fo20; /*求FOLLOW集合時(shí)使用*/

3、*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)生式*/void recur(char *point) /*完整的產(chǎn)生式在point中*/ int j,m=0,n=3,k;char tem

4、p20,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!=|&pointj!=0) tempm+=pointj+; leftcount=ch; memcpy(rightcount,temp,m); rightcountm=ch; rightcountm+1=0; m=0; count+; if

5、(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;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; me

6、mcpy(rightcount,temp,m); rightcountm=ch; rightcountm+1=0; count+; m=0;/*分解不含有左遞歸的產(chǎn)生式*/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(rightc

7、ount,temp,m); rightcountm=0; count+;m=0;/*讀入一個(gè)文法*/char 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(t,vt

8、,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) 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

9、 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； type2，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(jstrlen(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

10、所有由 推出的符號(hào)*/char temp10;int i;for(i=0;i=count-1;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

11、=count) return(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); temp0=rightik; temp

12、1=0; merge(empt,temp,1); if(result=0&icount) continue; else if(result=1&icount) 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(j=0;j=strlen(righti)-1;j+) if(in(rightij,non_ter)=0&in(rightij,termi

13、n)=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=vi;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

14、-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(rightj0=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&

15、k=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 /*如果右部為符號(hào)串*/for(j=0;j+) if(vj=p0) break;if(i=0) merge(firsti,first1j,2);else

16、 merge(TEMP,first1j,2);for(k=0;k=length-1;k+) empt0=0; if(_emp(pk)=1&k=0) merge(firsti,first1m,2); else merge(TEMP,first1m,2); else if(_emp(pk)=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,

17、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

18、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,followm,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*

19、/ merge(followi,followm,1); continue; if(Fm=0) 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

20、始化*/firstj0=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,first1j); 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);

21、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:);/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*/ memcp

22、y(selecti,firsti,strlen(firsti); selectistrlen(firsti)=0;for(j=0;j=strlen(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,selec

23、t0,strlen(select0);tempstrlen(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*/void 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=0;n-) Sp+=rightmn; Sq+strlen(rightm)=0; printf(S:%s str:,S);for(p=