編譯原理語法分析程序cc

1、 語法分析 （王君網(wǎng)絡(luò)1班） #include<stdlib.h>#include<stdio.h>#include<string.h>int count=0; /*分解的產(chǎn)生式的個數(shù)*/int number; /*所有終結(jié)符和非終結(jié)符的總數(shù)*/char start; /*開始符號*/char termin50; /*終結(jié)符號*/char non_ter50; /*非終結(jié)符號*/char v50; /*所有符號*/char left50; /*左部*/char right5050; /*右部*/char first5050,follow5050; /*各產(chǎn)生

2、式右部的first和左部的follow集合*/char first15050; /*所有單個符號的first集合*/char select5050; /*各單個產(chǎn)生式的select集合*/char f50,f50; /*記錄各符號的first和follow是否已求過*/char empty20; /*記錄可直接推出的符號*/char temp50; /*求follow時存放某一符號串的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ll(1)文法*/int m2020; /*分析表*/char choose; /*用戶輸入

3、時使用*/char empt20; /*求_emp()時使用*/char fo20; /*求follow集合時使用*/* 判斷一個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*/* 得到一個不是非終結(jié)符的符號*/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'|'后的首符號和左部相同*/for(j=n+1;j<=strlen(point)-1;j+) while(pointj!='|'&&poi

5、ntj!='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'|'后的首符號和左部不同*/leftcount=ch;rightcount0=''rightcount1='0'count+;for(j=n;j<=strlen(point)-1;j+) if(pointj!=&

6、#39;|') 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*/void non_re(char

7、*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;/* 讀入一個文法*/char grammer(char *t,c

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

9、#39; printf("請輸入文法的開始符號：");scanf("%c",&s);getchar();printf("請輸入文法產(chǎn)生式的條數(shù)："); scanf("%d",&i);getchar(); for(j=1;j<=i;j+)printf("請輸入文法的第%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!='-'|pj2!=&

10、#39;>')printf("ninput error!"); validity=0;return('0'); /*檢測輸入錯誤*/ 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);/* 將單個符號或符號串并入另一符號串*/void merge(char *d,char *s,int type) /*d是目標(biāo)符號串，s是源串，type1，源串中的' '一并并入目串； type2，源串中的' '不

11、并入目串*/ int i,j;for(i=0;i<=strlen(s)-1;i+) if(type=2&&si='');elsefor(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*/void emp(char c) /*即求所有由' '推出的符號*/char temp10;int i;for(i=0;i<=count-1;i+)if(righti0=c&&

12、amp;strlen(righti)=1)temp0=lefti;temp1='0'merge(empty,temp,1);emp(lefti);/* 求某一符號能否推出' '*/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) return(0);if(lefti=c) /*找一

13、個左部為c的產(chǎn)生式*/ j=strlen(righti); /*j為右部的長度*/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;temp1='0'merge(

14、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，報錯*/printf("nerror1!");validity=0;return(0);for(j=0;j<=strlen(righti)-1;j+)if(in(rig

15、htij,non_ter)=0&&in(rightij,termin)=0&&rightij!='') /*若右部某一符號不在非終結(jié)符、終結(jié)符中且不為' '，報錯*/printf("nerror2!");validity=0;return(0);return(1);/* 求單個符號的first*/void first2(int i) /*i為符號在所有輸入符號中的序號*/ char c,temp20;int j,k,m;c=vi;char ch=''emp(ch);if(in(c,termin)

16、=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(rightj0=c)continue;for(k=0;k+)if(vk=rightj0)break

17、;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='1'merge(first1i,first1m,2);else if(_emp(rightjk)=1&

18、;&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) /*如果右部為單個符號*/if(p0='') if(i>=0) firsti0='' firsti1='0'elsetemp

19、0=''temp1='0'elsefor(j=0;j+)if(vj=p0)break;if(i>=0) memcpy(firsti,first1j,strlen(first1j); firstistrlen(first1j)='0'elsememcpy(temp,first1j,strlen(first1j);tempstrlen(first1j)='0' else /*如果右部為符號串*/for(j=0;j+)if(vj=p0)break;if(i>=0) merge(firsti,first1j,2);elseme

20、rge(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);elsemerge(temp,first1m,2); else if(_emp(pk)=1&&k=length-1) temp0=''temp1='0'if(i>=0) merge(firsti,temp

21、,1); elsemerge(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) /*若為開始符號*/temp0='#'temp1='0'merge(followi,temp,1); for(j=0;j<=count-1;j+)if(i

22、n(c,rightj)=1) /*找一個右部含有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*/ for(m=0;m+)if(vm=leftj)break; /*m為產(chǎn)生式左部非終結(jié)符在所有符號中的序號*/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

23、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后面的符號串能推出*/ if(in(vm,fo)=1) /*避免循環(huán)遞歸*/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=righ

24、tjn; 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ll(1)文法*/int ll1() int i,j,length,result=1;char temp50;for(j=0;j<=49;j+) /*初始化*/firstj0='0' followj0='0'first1j0='0'selectj0='0'tempj='0'tempj='0'

25、;fj='0'fj='0'for(j=0;j<=strlen(v)-1;j+) first2(j); /*求單個符號的first集合*/printf("nfirst1:");for(j=0;j<=strlen(v)-1;j+)printf("%c:%s ",vj,first1j); printf("nempty:%s",empty);printf("n:n_emp:");for(j=0;j<=strlen(v)-1;j+) printf("%d "

26、;,_emp(vj);for(i=0;i<=count-1;i+) first(i,righti); /*求first*/printf("n");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:"); for(i=0;i<=st

27、rlen(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<=strlen(righti)-1;j+)result*=_emp(rightij);if(strlen(righti)=1&&righti0='')result=1;if(result=1)for(j=

28、0;j+)if(vj=lefti)break;merge(selecti,followj,1);printf("nselect:");for(i=0;i<=count-1;i+) printf("%s ",selecti);memcpy(temp,select0,strlen(select0);tempstrlen(select0)='0'for(i=1;i<=count-1;i+) /*判斷輸入文法是否為ll(1)文法*/ length=strlen(temp);if(lefti=lefti-1)merge(temp,sel

29、ecti,1);if(strlen(temp)<length+strlen(selecti)return(0);elsetemp0='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

30、='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*/for(j=0;j<=strlen(selecti)-1;j+)if(in(selectij,termin)=1)for(k=0;k+)if(termink=selectij)break; /*k為產(chǎn)生式右部終結(jié)符的序號*/ mmk=i;/* 總控算法*/void syntax()int i,j,k,m,n,p,q; char ch;char s50,str50; printf("請輸入該文法的句

31、型：");scanf("%s",str);getchar();i=strlen(str);stri='#'stri+1='0's0='#'s1=start;s2='0'j=0;ch=strj; while(1)if(in(sstrlen(s)-1,termin)=1) if(sstrlen(s)-1!=ch)printf("n該符號串不是文法的句型！"); return;else if(sstrlen(s)-1='#') printf("n該符號串是文法的

32、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=strlen(termin)printf("n詞法錯誤！");return;if(mik=-1)printf("n語法錯誤！");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("ns:%s str:",s);for(p=j;