编译原理实验递归子程序法

1、递归子程序法：#include "stdio.h"#include "stdlib.h"void display();char read(); /读取字符函数void write();char lookhead;void E();void T();void G();void S();void F();void match(char ch);void error(); /出错处理char string10;int top;int main()display();write();lookhead=read();E();puts(string);printf(

2、"为合法字符串！n");system("pause");return 0;void E()printf("E->TG n");T();G();void G()if(lookhead='+')printf("G->+TG n");match('+');T();G();else if(lookhead='-')printf("G->-TG n");match('-');T();G();elseprintf("

3、G-> n");void T()printf("T->FS n");F();S();void S()if(lookhead='*')printf("s->*FS n");match('*');F();S();else if(lookhead='/')printf("S->/FS n");match('/');elseprintf("S-> n");void F()if(lookhead='(')p

4、rintf("F->(E) n");match('(');E();match(')');else if(lookhead='i')match('i');else error();void match(char ch)lookhead=read();void write()char cha;top=0;printf("请输入待分析字符串：n");doscanf("%c",&cha);stringtop=cha;top+;while(cha!='#

5、9;);top=0;char read()char cha;cha=stringtop;top+;return cha;void error()puts(string);printf("为非法字符串！n");system("pause");exit(0);void display()printf("班级：10级计本一班n");printf("学号：1004011026n");printf("姓名：王晓龙n");LL(1)分析方法：#include "stdio.h"#incl

6、ude "stdlib.h"#include "string.h"char S,X,a; /S文法的开始符号，X当前栈顶符号的工作单元，a当前输入符号的工作单元char string10; /存放输入的句型int count=0;/计数器int step=0; /记录步骤char M166; /存放产生式int record; /记录当前找到的M中产生式的下标char stack10; /栈int top;char Vt9="i+-*/()" /终结符号int i;void error(); /出错函数void init(); /初始

7、化预测分析表int judge(char x,char a);void analyse();void main()init(); /初始化预测分析表int i;int mark1=0;char ch;top=-1;printf("请输入要分析的字符串：n");string0='#'i=1;doscanf("%c",&ch);stringi=ch;i+;while(ch!='#');printf("步骤tt分析栈tt剩余字符串n");top+;stacktop=string0;count+;top

8、+;stacktop='E'step+;printf("%dtt",step);for(int i=0;i<=top;i+)printf("%c",stacki);printf("tt");i=1;while(stringi!='0')printf("%c",stringi);i+;printf("n");analyse();system("pasue");void error()printf("分析失败！n");sy

9、stem("pause");exit(0);void init() /初始化预测分析表 -已经产生式右部反转过来strcpy(M0,"EiGT");strcpy(M1,"E(GT");strcpy(M2,"G+GT+");strcpy(M3,"G)$");strcpy(M4,"G#$");strcpy(M5,"G-GT-");strcpy(M6,"TiSF");strcpy(M7,"T(SF");strcpy(M8,

10、"S+$");strcpy(M9,"S*SF*");strcpy(M10,"S)$");strcpy(M11,"S#$");strcpy(M12,"S/SF/");strcpy(M13,"S-$");strcpy(M14,"Fii");strcpy(M15,"F()E(");int judge(char x,char b)for(int i=0;i<16;i+)if(Mi0=x && Mi1=b)record=i;

11、return 1;return 0;void analyse()int mark1=0;a=stringcount;X=stacktop;top-;for(int i=0;i<=8;i+)if(X=Vti)if(X=a)count+;else error();mark1=1;break;if(mark1=0)if(X='#')if(X=a)printf("分析成功！n"); system("pause");exit(0);else error();if(X!='#')if(!judge(X,a)error();els

12、efor(int i=2;i<5;i+)if(Mrecordi!='0' && Mrecordi!='$')top+;stacktop=Mrecordi;step+;printf("%dtt",step);for(int i=0;i<=top;i+)printf("%c",stacki);printf("tt");i=count;while(stringi!='0')printf("%c",stringi);i+;printf("

13、n");analyse();算符优先文法：#include <stdio.h>#include <string.h>#include <stdlib.h>char data99= ' ','+','-','*','/','(',')','i','#', '+','>','>','<','<','&

14、lt;','>','<','>', '-','>','>','<','<','<','>','<','>', '*','>','>','>','>','<','>','<&

15、#39;,'>', '/','>','>','>','>','<','>','<','>', '(','<','<','<','<','<','=','<',' ', ')','&g

16、t;','>','>','>',' ','>',' ','>', 'i','>','>','>','>',' ','>',' ','>', '#','<','<','<','<

17、;','<',' ','<','='void analyse(char a,int n)int i=0,j=0,k=0,t=0,h=0,g=0; char ch,r; /当前符号 char A30;/符号栈 A0='#' ch=a0; while(ch!='0') do while(Ak='N') k-; while(Ak!=data0j) j+; while(ch!=datai0) i+;r=dataji; if(r='>') g=k; i

18、f(Ag-1='N') g-; Ag='N' else Ag='N' k=g; for(h=0;h<=g;h+) printf("%c",Ah); printf("n"); else if(r='=') if(k=0) printf("分析成功!n"); system("pause"); return ; else printf("分析失败!n");exit(0); i=0,j=0; while(r!='<'); g+;Ag=ch;k=g; t+; ch=at;j=0,i=0;for(h=0;h<=k;h+)printf("%c",Ah);printf("n"); void main()char a30,B30;FILE * fp; char c,