编译原理实验二语法分析器LL(1)实现.doc

编译原理程序设计实验报告表达式语法分析器的设计班级：计算机1306班姓名：张涛学号：20133967实验目标：用LL（1）分析法设计实现表达式语法分析器实验内容：概要设计：通过对实验一的此法分析器的程序稍加改造，使其能够输出正确的表达式的token序列。然后利用LL（1）分析法实现语法分析。数据结构：int op=0; /当前判断进度char ch; /当前字符char nowword10=; /当前单词char operate4=+,-,*,/; /运算符char bound2=(,); /界符struct Token int code; char ch10; /Token定义struct Token tokenlist50; /Token数组struct Token tokentemp; /临时Token变量struct Stack /分析栈定义 char *base; char *top; int stacksize;分析表及流程图关键函数：int IsLetter(char ch) /判断ch是否为字母int IsDigit(char ch) /判断ch是否为数字int Iskey(char *string) /判断是否为关键字int Isbound(char ch) /判断是否为界符int Isboundnum(char ch) /给出界符所在token值int init(STack *s) /栈初始化int pop(STack *s,char *ch) /弹栈操作int push(STack *s,char ch) /压栈操作void LL1(); /分析函数源程序代码：（加入注释）#include#include#include#include#include int op=0; /当前判断进度char ch; /当前字符char nowword10=; /当前单词char operate4=+,-,*,/; /运算符char bound2=(,); /界符struct Token int code; char ch10; /Token定义struct Token tokenlist50; /Token数组struct Token tokentemp; /临时Token变量struct Stack /分析栈定义 char *base; char *top; int stacksize;typedef struct Stack STack;int init(STack *s) /栈初始化 (*s).base=(char*)malloc(100*sizeof(char); if(!(*s).base) exit(0); (*s).top=(*s).base; (*s).stacksize=100; printf(初始化栈n); return 0;int pop(STack *s,char *ch) /弹栈操作 if(*s).top=(*s).base) printf(弹栈失败n); return 0; (*s).top-; *ch=*(*s).top); printf(%c,*ch); return 1;int push(STack *s,char ch) /压栈操作 if(*s).top-(*s).base=(*s).stacksize) (*s).base=(char*)realloc(*s).base,(*s).stacksize+10)*sizeof(char); if(!(*s).base) exit(0); (*s).top=(*s).base+(*s).stacksize; (*s).stacksize+=10; *(*s).top=ch; *(*s).top+; return 1;void LL1();int IsLetter(char ch) /判断ch是否为字母 int i;for(i=0;i=a&ch=A&ch=Z)return 1; return 0; int IsDigit(char ch) /判断ch是否为数字 int i; for(i=0;i=0&ch=9) return 1; return 0; int Isbound(char ch) /判断是否为界符 int i; for(i=0;i2;i+) if(ch=boundi) return i+1; return 0;int Isoperate(char ch) /判断是否为运算符 int i; for(i=0;i4;i+) if(ch=operatei) return i+3; return 0;int main()FILE *fp;int q=0,m=0;char sour200= ;printf(请将源文件置于以下位置并按以下方式命名：F:2.txtn);if(fp=fopen(F:2.txt,r)=NULL) printf(文件未找到！n); else while(!feof(fp) if(isspace(ch=fgetc(fp); else sourq=ch; q+; int p=0; printf(输入句子为：n); for(p;p=q;p+) printf(%c,sourp); printf(n); int state=0,nowlen=0; BOOLEAN OK=TRUE,ERR=FALSE; int i,flagpoint=0; for(i=0;iq;i+) if(souri=#) tokenlistm.code=#; switch(state) case 0: ch=souri; if(Isbound(ch) if(ERR) printf(无法识别n); ERR=FALSE; OK=TRUE; else if(!OK) printf(标识符n,nowword); tokentemp.code=10; tokentemp.ch10=nowword10; tokenlistm=tokentemp; m+; OK=TRUE; state=4; else if(IsDigit(ch) if(OK) memset(nowword,0,strlen(nowword); nowlen=0; nowwordnowlen=ch; nowlen+; state=3; OK=FALSE; break; else nowwordnowlen=ch; nowlen+; else if(IsLetter(ch) if(OK) memset(nowword,0,strlen(nowword); nowlen=0; nowwordnowlen=ch; nowlen+; OK=FALSE; else nowwordnowlen=ch; nowlen+; else if(Isoperate(ch) if(!OK) printf(标识符n,nowword); tokentemp.code=10; tokentemp.ch10=nowword10; tokenlistm=tokentemp; m+; OK=TRUE; printf(运算符n,Isoperate(ch),ch); tokentemp.code=Isoperate(ch); tokentemp.ch10=ch; tokenlistm=tokentemp; m+; break; case 3: if(IsLetter(ch) printf(错误n); nowwordnowlen=ch; nowlen+; ERR=FALSE; state=0; break; if(IsDigit(ch=souri) nowwordnowlen=ch; nowlen+; else if(souri=.&flagpoint=0) flagpoint=1; nowwordnowlen=ch; nowlen+; else printf(数字n,nowword); i-; state=0; OK=TRUE; tokentemp.code=20; tokentemp.ch10=nowword10; tokenlistm=tokentemp; m+; break; case 4: i-; printf(界符n,Isbound(ch),ch); tokentemp.code=Isbound(ch); tokentemp.ch10=ch; tokenlistm=tokentemp; m+; state=0; OK=TRUE; break; printf(tokenlist值为%dn,m); int t=0; tokenlistm+1.code=r; m+; for(t;tm;t+) printf(tokenlist%d值为%dn,t,tokenlistt.code); LL1(); printf(tokenlist值为%dn,m); if(op+1=m) printf(OK!); else printf(WRONG!); return 0;void LL1() STack s; init(&s); push(&s,#); push(&s,E); char ch; int flag=1; do pop(&s,&ch); printf(输出栈顶为%cn,ch); printf(输出栈顶为%dn,ch); printf(当前p值为%dn,op); if(ch=()|(ch=)|(ch=+)|(ch=-)|(ch=*)|(ch=/)|(ch=10)|(ch=20) if(tokenlistop.code=1|tokenlistop.code=20|tokenlistop.code=10|tokenlistop.code=2|tokenlistop.code=3|tokenlistop.code=4|tokenlistop.code=5|tokenlistop.code=6) op+; else printf(WRONG!); exit(0); else if(ch=#) if(tokenlistop.code=0) flag=0; else printf(WRONG!); exit(0); else if(ch=E) printf(进入En); if(tokenlistop.code=10|tokenlistop.code=20|tokenlistop.code=1) push(&s,R); printf(将R压入栈n); push(&s,T); else if(ch=R) printf(进入Rn); if(tokenlistop.code=3|tokenlistop.code=4) push(&s,R); push(&s,T); printf(将T压入栈n); push(&s,+); if(tokenlistop.code=2|tokenlistop.code=0) else if(ch=T) printf(进入Tn); if(tokenlistop.code=10|tokenlistop.code=20|tokenlistop.code=1) push(&s,Y); push(&s,F); else if(ch=Y) printf(进入Yn); if(tokenlistop.code=5|tokenlistop.code=6) push(&s,Y); push(&s,F); push(&s,*); else if(tokenlistop.code=3|tokenlistop.code=2|tokenlistop.code=0|tokenlistop.code=4) else if(ch=F) printf(进入Fn); if(tokenlistop.code=