实验五 LL1文法识别程序设计

班级: 学号:姓名:PAGE1实验五LL(1)文法识别程序设计一、实验目的通过LL(1)文法识别程序的设计理解自顶向下的语法分析思想。二、实验重难点理解并实现LL(1)文法三、实验内容与要求编写LL(1)文法识别程序四、实验学时4课时五、实验设备与环境VisualC++6.0六、实验过程熟悉VisualC++6.0集成开发环境，掌握VC下创建工程的方法和步骤；编写程序能识别文法符号的头符号集；编写程序能识别文法符号的后继符号集；设计一个能判断文法是否为LL(1)文法的程序。参考程序：/************************************//*程序名称：LL(1)文法分析程序*//*E->E+T|E-T|T*//*T->T*F|T/F|F*//*F->(E)|i*//*程序版本：1.0Final*//************************************//********************************************//*程序相关说明*//*A=E’B=T’*//*0=E1=E’2=T3=T’4=F*//*0=i1=+2=-3=*4=/5=(6=)7=#*//************************************/#include"stdio.h"#include"malloc.h"typedefstructLchar{charchar_ch;structLchar*next;}Lchar;Lchar*p,*h,*temp,*top,*base;charcurchar;charcurtocmp;intright;inttable[5][8]={{1,0,0,0,0,1,0,0},{0,1,1,0,0,0,1,1},{1,0,0,0,0,1,0,0},{0,1,1,1,1,0,1,1},{1,0,0,0,0,1,0,0}};inti,j;voidpush(charpchar){temp=(Lchar*)malloc(sizeof(Lchar));temp->char_ch=pchar;temp->next=top;top=temp;}voidpop(void){curtocmp=top->char_ch;if(top->char_ch!='#')top=top->next;}voiddoforpush(intt){switch(t){case0:push('A');push('T');break;case5:push('A');push('T');break;case11:push('A');push('T');push('+');break;case12:push('A');push('T');push('-');break;case20:push('B');push('F');break;case25:push('B');push('F');break;case33:push('B');push('F');push('*');break;case34:push('B');push('F');push('/');break;case40:push('i');break;case45:push(')');push('E');push('(');}}voidchangchartoint(){switch(curtocmp){case'A':i=1;break;case'B':i=3;break;case'E':i=0;break;case'T':i=2;break;case'F':i=4;}switch(curchar){case'i':j=0;break;case'+':j=1;break;case'-':j=2;break;case'*':j=3;break;case'/':j=4;break;case'(':j=5;break;case')':j=6;break;case'#':j=7;}}voiddosome(void){intt;for(;;){pop();curchar=h->char_ch;printf("\n%c\t%c\n",curchar,curtocmp);if(curtocmp=='#'&&curchar=='#')break;if(curtocmp=='A'||curtocmp=='B'||curtocmp=='E'||curtocmp=='T'||curtocmp=='F'){if(curtocmp!='#'){changchartoint();if(table[i][j]){t=10*i+j;doforpush(t);continue;}else{right=0;break;}}elseif(curtocmp!=curchar){right=0;break;}elsebreak;}elseif(curtocmp!=curchar){right=0;break;}else{h=h->next;continue;}}}voidmain(void){charch;right=1;base=(Lchar*)malloc(sizeof(Lchar));base->next=NULL;base->char_ch='#';temp=(Lchar*)malloc(sizeof(Lchar));temp->next=base;temp->char_ch='E';top=temp;h=(Lchar*)malloc(sizeof(Lchar));h->next=NULL;p=h;do{ch=getchar();putchar(ch);if(ch=='i'||ch=='+'||ch=='-'||ch=='*'||ch=='/'||ch=='('||ch==')'||ch=='#'){temp=(Lchar*)malloc(sizeof(Lchar));temp->next=NULL;temp->char_ch=ch;h->next=temp;h=h->next;}else{temp=p->next;printf("\nInputawrongchar!Inputagain:\n");for(;;){if(temp!=NULL)printf("%c",temp->char_ch);elsebreak;temp=temp->next;}}}while(ch!='#');p=p->next;h=p;dosome();if(right)printf("\nOK!\n");elseprintf("\nError!\n");getchar