语法分析器C语言实现

#include"stdlib.h"
#include"stdio.h"
#include"string.h"
#include <windows.h>
typedef struct
{
    charR;
    charr;
    intflag;
}array;
array F[30];

typedef struct
{
    charE;
    chare;
}charLode;

typedef struct
{
    charLode*base;
    inttop;
}charstack;

char str[80][80],arr[80][80],brr[80][80];

int m,kk,p,ppp,FF=1;
char r[20];
int crr[30][30],FLAG=0;
char ccrr1[1][30],ccrr2[30][1];
void Initstack(charstack *s)
{
 s->base=(charLode*)malloc(30*sizeof(charLode));
   s->top=-1;
}

void push(charstack *s,charLode w)
{
   s->top++;
  s->base[s->top].E=w.E;
  s->base[s->top].e=w.e;
}

void pop(charstack *s,charLode *w)
{
  w->E=s->base[s->top].E;
  w->e=s->base[s->top].e;
   s->top--;
}

int IsEmpty(charstack s)
{
   if(s.top==-1)
       return 1;
    else
    return 0;
}
int IsLetter(char ch)
{
   if(ch>='A'&&ch<='Z')
      return 1;
    else
  return 0;
}

int judge1(int n)
{
    intj=3,flag=1,i;
   for(i=0;i<=n;i++)
  while(str[i][j]!='\0')
  {
           char a=str[i][j];
           char b=str[i][j+1];
           if(IsLetter(a)&&IsLetter(b))
   {
    flag=0;
    break;
   }
           else
    j++;
  }
  return flag;
}

void judge2(int n)
{
 int i;
   for(i=0;i<=n;i++)
   if(str[i][3]=='~'||judge1(n)==0||FLAG==1)
    {
  printf("grammar G is notoperator priority grammar!\n");
  FF=0;
  break;
 }
   if(i>n)
  printf("grammar G is operatorpriority grammar!\n");
}

int search1(char r[],int kk,char a)
{
 int i;
   for(i=0;i<kk;i++)
       if(r[i]==a)
           break;
   if(i==kk)
  return 0;
    else
  return 1;
}

void createF(int n)
{
    intk=0,i=1;
    charc;
    int j;
    chart[10];
   t[0]=str[0][0];
   while(i<=n)
 {
       if(t[k]!=str[i][0])
  {
   k++;
   t[k]=str[i][0];
   i++;
  }
       else
   i++;
 }
    kk=0;
   for(i=0;i<=n;i++)
 {
  j=3;
       while(str[i][j]!='\0')
  {
           c=str[i][j];
           if(IsLetter(c)==0)
   {
               if(!search1(r,kk,c))
               r[kk]=c;
    kk++;
   }
           j++;
  }
    }
    m=0;
   for(i=0;i<k;i++)
       for(j=0;j<kk-1;j++)
  {
           F[m].R=t[i];
           F[m].r=r[j];
           F[m].flag=0;
           m++;
  }
}

void search(charLode w)
{
 int i;
   for(i=0;i<m;i++)
       if(F[i].R==w.E&&F[i].r==w.e)
  {
   F[i].flag=1;
   break;
  }
}

void FirstVT(int n)
{
    charstacksta;
    charLodeww;
    charLodew;
    inti=0,k;
    chara,b;
   Initstack(&sta);
   while(i<=n)
 {
       k=3;
       w.E=str[i][0];
       a=str[i][k];
      b=str[i][k+1];
       if(!IsLetter(a))
  {
           w.e=a;
           push(&sta,w);
           search(w);
           i++;
  }
       elseif(IsLetter(a)&&b!='\0'&&!IsLetter(b))
  {
           w.e=b;
           push(&sta,w);
           search(w);
           i++;
  }
       else
   i++;
 }
   while(!IsEmpty(sta))
 {
       pop(&sta,&ww);
       for(i=0;i<=n;i++)
  {
           w.E=str[i][0];
           if(str[i][3]==ww.E&&str[i][4]=='\0')
   {
               w.e=ww.e;
               push(&sta,w);
               search(w);
               break;
   }
   elseif(str[i][3]==ww.E&&w.E!=ww.E)
   {
    w.e=ww.e;
               push(&sta,w);
               search(w);
               break;
   }
   
  }
 }
    p=0;
   k=1;i=1;
   while(i<m)
 {
       if(F[i-1].flag==1)
  {
           arr[p][0]=F[i-1].R;
           arr[p][k]=F[i-1].r;
  }
       while(F[i].flag==0&&i<m)
           i++;
       if(F[i].flag==1)
  {
           if(F[i].R==arr[p][0])
               k++;
           else
   {
    arr[p][k+1]='\0';
    p++;
    k=1;
   }
           i++;
  }
 }  
}

void LastVT(int n)
{
    charstacksta;
    charLodew;
    charLodeee;
    chara,b;
    intk,i;
   for(i=0;i<m;i++)
       F[i].flag=0;
    i=0;
   Initstack(&sta);
   while(i<=n)
 {
       int k=strlen(str[i]);
       w.E=str[i][0];
       a=str[i][k-1];
       b=str[i][k-2];
       if(!IsLetter(a))
  {
           w.e=a;
           push(&sta,w);
           search(w);
           i++;
  }
       elseif(IsLetter(a)&&!IsLetter(b))
  {
           w.e=b;
           push(&sta,w);
           search(w);
           i++;
  }
       else
   i++;
 }

   while(!IsEmpty(sta))
 {
       pop(&sta,&ee);
       for(i=0;i<=n;i++)
  {
           w.E=str[i][0];
           if(str[i][3]==ee.E&&str[i][4]=='\0')
   {
               w.e=ee.e;
               push(&sta,w);
               search(w);
   }
  }
 }
   k=1;
 i=1;
    ppp=0;
   while(i<m)
 {
       if(F[i-1].flag==1)
  {
           brr[ppp][0]=F[i-1].R;
           brr[ppp][k]=F[i-1].r;
  }
       while(F[i].flag==0&&i<m)
           i++;
       if(F[i].flag==1)
  {
           if(F[i].R==arr[ppp][0])
               k++;
           else
   {
    brr[ppp][k+1]='\0';
    ppp++;
    k=1;
   }
           i++;
  }
 }  
}

void createYXB(int n)
{
    inti,j;
    intI,mm,pp,J;
   for(j=1;j<=kk;j++)
       ccrr1[0][j]=r[j-1];
   for(i=1;i<=kk;i++)
       ccrr2[i][0]=r[i-1];
   for(i=1;i<=kk;i++)
       for(j=1;j<=kk;j++)
           crr[i][j]=0;
   I=0,J=3;
   while(I<=n)
    {
       if(str[I][J+1]=='\0')
  {
   I++;
   J=3;
  }
       else
  {
           while(str[I][J+1]!='\0')
   {
               char aa=str[I][J];
               char bb=str[I][J+1];
               if(!IsLetter(aa)&&!IsLetter(bb))
    { 
                   for(i=1;i<=kk;i++)
     {
                       if(ccrr2[i][0]==aa)
                           break;
                   }
                   for(j=1;j<=kk;j++)
     {
                       if(ccrr1[0][j]==bb)
                           break; 
                   }
                   if(crr[i][j]==0)
                       crr[i][j]=1;
                   else
     {
      FLAG=1;
      I=n+1;
     }
                   J++;
    }
               if(!IsLetter(aa)&&IsLetter(bb)&&str[I][J+2]!='\0'&&!IsLetter(str[I][J+2]))
    { 
                   for(i=1;i<=kk;i++)
     {
                       if(ccrr2[i][0]==aa)
                           break;
                   }
                   for(j=1;j<=kk;j++)
     {
                       if(ccrr1[0][j]==str[I][J+2])
                           break;
                   }
                   if(crr[i][j]==0)
                       crr[i][j]=1;
                   else
     {
      FLAG=1;
      I=n+1;
     }
    }
               if(!IsLetter(aa)&&IsLetter(bb))
    { 
                   for(i=1;i<=kk;i++)
     {
                       if(aa==ccrr2[i][0])
                           break;
                   }
                   for(j=0;j<=p;j++)
     {
                       if(bb==arr[j][0])
                           break;
                   }
                   for(mm=1;arr[j][mm]!='\0';mm++)
     {
                       for(pp=1;pp<=kk;pp++)
      {
                           if(ccrr1[0][pp]==arr[j][mm])
                               break;
      }
                       if(crr[i][pp]==0)
                           crr[i][pp]=2;
                       else
      {
       FLAG=1;
       I=n+1;
      }
     }
                   J++;
    }
               if(IsLetter(aa)&&!IsLetter(bb))
    {
                   for(i=1;i<=kk;i++)
     {
                       if(ccrr1[0][i]==bb)
                           break;
     }
                   for(j=0;j<=ppp;j++)
     {
                       if(aa==brr[j][0])
                           break;
     }
                   for(mm=1;brr[j][mm]!='\0';mm++)
     { 
                       for(pp=1;pp<=kk;pp++)
      {
                           if(ccrr2[pp][0]==brr[j][mm])
                               break;
      }
                       if(crr[pp][i]==0)
                           crr[pp][i]=3;
                       else
      {
       FLAG=1;
       I=n+1;
      }
      
     }
     J++;
    }
           }
       }
    }
}

int judge3(char s,char a)
{
    inti=1,j=1;
   while(ccrr2[i][0]!=s)
       i++;
   while(ccrr1[0][j]!=a)
       j++;
   if(crr[i][j]==3)
  return 3;
    elseif(crr[i][j]==2)
       return 2;
    elseif(crr[i][j]==1)
       return 1;
    else return0;
}

void print(char s[],char STR[][20],int q,int u,int ii,int k)
{
 int i;
 printf("%d\t\t",u);
   for(i=0;i<=k;i++)
       
  printf("%c",s[i]);
      
 printf("\t\t");
   for(i=q;i<=ii;i++)
      
  printf("%c",STR[0][i]);
  
 printf("\t\t");
}

void process(char STR[][20],int ii)
{
    intk=0,q=0,u=0,b,i,j;
    chars[40],a;
   printf("step\t\tcharstack\tinputstring\tAction\n");
   s[k]='#';
   print(s,STR,q,u,ii,k);
 printf("ready\n");
    k++;
 u++;
   s[k]=STR[0][q];
    q++;
   print(s,STR,q,u,ii,k);
 printf("shift\n");
   while(q<=ii)
 {
       a=STR[0][q];
       if(!IsLetter(s[k]))
   j=k;
       else
   j=k-1;
       b=judge3(s[j],a);
       if(b==3)
  {
           while(IsLetter(s[j-1]))
               j--;
           for(i=j;i<=k;i++)
               s[i]='\0';
           k=j;s[k]='G';u++;
           print(s,STR,q,u,ii,k);
   printf("reduce\n");
  }
       else if(b==2||b==1)
  {
           k++;
           s[k]=a;
           u++;
           q++;
           print(s,STR,q,u,ii,k);
           if(s[0]=='#'&&s[1]=='N'&&s[2]=='#')
               printf("shift\n");
           else
    printf("accept\n");
  }
       else
  {
   printf("error\n");
   break;
  }
 }
   if(s[0]=='#'&&s[1]=='N'&&s[2]=='#')
  printf("Reduction issuccessful\n");
    else
  printf("Reductionfails\n");
}

void main()
{
    intn,i,j,o;
    intii;
   printf("please input the number of grammer G defined:");
   scanf("%d",&n);
   printf("please input the grammer G ");
   printf("\n");
   for(i=0;i<n;i++)
 {
     scanf("%s",str[i]);
     j=strlen(str[i]);
     str[i][j]='\0';
 }
   str[i][0]='Q';
   str[i][1]='-';
   str[i][2]='>';
   str[i][3]='#';
   str[i][4]=str[0][0];
   str[i][5]='#';
   str[i][6]='\0';
 printf("Creation style that you define asfollows:\n");
   for(i=0;i<=n;i++)
  printf("%s\n",str[i]);
   if(judge1(n)==0)
  printf("Grammar G is notoperator grammar !\n");
   if(judge1(n)==1)
 {
  printf("grammar G is theoperator of grammar !\n");
       createF(n);
       FirstVT(n);
       LastVT(n);
       createYXB(n);
 }
   judge2(n);
   if(FLAG==0)
    {
       for(i=0;i<=p;i++)
       {
   printf("FirstVT(%c)={",arr[i][0]);
           for(o=1;arr[i][o+1]!='\0';o++)
    printf("%c,",arr[i][o]);
   printf("%c}\n",arr[i][o]);
       }
 }
  printf("FirstVT(Q)={#}\n");
       for(i=0;i<=ppp;i++)
  {
   printf("LastVT(%c)={",arr[i][0]);
           for(o=1;brr[i][o+1]!='\0';o++)
    printf("%c,",brr[i][o]);
   printf("%c}\n",brr[i][o]);
  }
  printf("LastVT(Q)={#}\n");
  printf("Priority table is asfollows:\n");
       for(i=1;i<kk;i++)
  {
   printf("  ");
   printf("%c",ccrr1[0][i]);
  }
  printf("\n");
       for(i=1;i<kk;i++)
  {
   printf("%c ",ccrr2[i][0]);
           for(j=1;j<kk;j++)
   {
               if(crr[i][j]==0)
     printf("");
               else if(crr[i][j]==1)
     printf("=");
               else if(crr[i][j]==2)
     printf("<");
               else if(crr[i][j]==3)
                   printf(">");
    printf("  ");
   }
   printf("\n");
  }
  
 
   if(FF==1)
   {
       char STR[1][20];
  printf("Please input the stringto the Statute:\n");
  scanf("%s",STR[0]);
  //getchar();
       //gets(STR[0]);
       ii=strlen(STR[0]);
       STR[0][ii]='#';
  printf("theAnalysis  are as follow:\n");
       process(STR,ii);
   }
}