词法分析

开发平台：
C/C++

TEXT.C：源码内容
							#include"stdio.h"
#include"string.h"
#include"ctype.h"
int operation(char ch);
int keyword(char c[]);
int symbol(char ch);
spy(char m[],char n[],int i,int j);
char a[200];
char t;
int main()
{
 char sourcename[10];
 char objectname[10];
 FILE *fp;
 char ch;
 int i=0,j;
 char store[30];
 printf("please input sourcefile:");
 scanf("%s",sourcename);
 if((fp=fopen(sourcename,"r"))==NULL)
 {
  printf("file error! please input again.n");
  exit(0);
 }
 printf("n");
 do
 {
  ch=fgetc(fp);
  if(ch=='n') continue;
  a[i]=ch;
  i++;
}while(!feof(fp));
fclose(fp);
printf("Please input objectfile name:");
scanf("%s",objectname);
printf("n");
if((fp=fopen(objectname,"w"))==NULL)
{
 printf("Open Objectfile failure!n");
 exit(0);
}
j=0;
for(i=0;i<(strlen(a)-1);i++)
{
   if(a[i]==' ') continue;
   if(isdigit(a[i]))   {t='5';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputc(a[i],fp);fputc('"',fp);fputc('n',fp);continue;}
   if(operation(a[i])) {t='3';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputc(a[i],fp);fputc('"',fp);fputc('n',fp);continue;}
   if(symbol(a[i]))    {t='2';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputc(a[i],fp);fputc('"',fp);fputc('n',fp);continue;}
   if(isalpha(a[i]))
   {
     j=i+1;
     while(1)
     {
		 if(isalpha(a[j])) {j++;continue;}
	     break;
	 }
     spy(store,a,i,j);
	 if(keyword(store))   {t='1';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputs(store,fp);fputc('"',fp);fputc('n',fp);i=j-1;continue;}
	 {t='6';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputs(store,fp);fputc('"',fp);fputc('n',fp);i=j-1;continue;}
   }
   if((a[i]=='<')&&(a[i+1]!='=')||(a[i]=='>'&&a[i+1]!='=')) {t='4';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputc(a[i],fp);fputc('"',fp);fputc('n',fp);continue;}
   if((a[i]=='<'&&a[i+1]=='=')||(a[i]=='>'&&a[i+1]=='=')||(a[i]=='='&&a[i+1]=='=')) {t='4';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputc(a[i],fp);fputc(a[i+1],fp);fputc('"',fp);fputc('n',fp);i++;continue;}
   {t='6';fputc('"',fp);fputc(t,fp);fputc('"',fp);fputc(',',fp);fputc('"',fp);fputc(a[i],fp);fputc('"',fp);fputc('n',fp);}
}
}
int operation(char ch)
{
if(ch=='+'||ch=='-'||ch=='*'||ch=='/')
 return 1;
 else return 0;
}
int keyword(char c[])
{
 char  key[][8]={"int","float","char","double","long","if","else","while","for"};
 int j=0,k=0;
 for(j=0;j<9;j++)
 {
  if(!strcmp(c,key[j])) {k=1;break;}
 }
 if(k==1) return 1;
 else return 0;
}
int symbol(char ch)
{
 if(ch=='{'||ch=='}'||ch==','||ch==';'||ch=='('||ch==')'||ch=='"'||ch=='=')
  return 1;
  else return 0;
}
spy(char m[],char n[],int i,int j)
{
 int z=0,k=0;
 for(z=i;z<j;z++)
 {m[k]=n[z];k++;}
 m[k]='';
}

						