语法分析器运行结果显示与实验报告

#include<string.h>

int isterminal(char a)
{if((a=='i')||(a=='+')||(a=='*')||(a=='(')||(a==')')||(a=='$'))
 return(1);
 else return(0);
}

int notin(char a,char *b)
{char *c;
 for(c=b;(*c)!='\0';c++)
 {if((*c)==a) break;
 }
 if((*c)=='\0') return(1);
 else return(0);
}

void add(char *g,char *q,char *a)
{char *tem;
 tem=a;
 for(;(*tem)!='\0';tem++)
 {if(notin((*tem),g))
  {(*q)=(*tem);
   q++;
   (*q)='\0';
  }
 }
}

int maybenull(char E)

{char product[8][5]={"SBA","A+BA","A","BDC","C*DC","C","D(S)","Di"};
 int i;
 for(i=0;i<8;i++)
 {if((product[i][0]==E)&&(product[i][1]=='\0'))
  break;
 }
 if(i<8) return(1);
 else if(i>=8) return(0);
}

char *first(char E)
{char product[8][5]={"SBA","A+BA","A","BDC","C*DC","C","D(S)","Di"};
 char group[200],*q;
 int i,j;
 q=group;
 if(isterminal(E))
 {(*q)=E;
  q++;
  (*q)='\0';
 }
 else
 {for(i=0;i<8;i++)
  {if(product[i][0]==E)
   {if(isterminal(product[i][1])&&notin(product[i][1],group))
    {(*q)=product[i][1];
     q++;
     (*q)='\0';
    }
    else if((!isterminal(product[i][1]))&&((product[i][1])!='\0'))
    {add(group,q,first(product[i][1]));