词法分析c程序.txt

编译原理中的词法分析C语言实现 编译原理中的词法分析C语言实现

词法分析C程序
/* Note:Your choice is C IDE */
/*#include "stdafx.h"*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <malloc.h>
#include <ctype.h>
#include <conio.h>
#define NULL 0
FILE *fp;
char ch;
char *keyword[8]={"do","begin","else","end","if","then","var","while"};
char *operatornum[4]={"+","-","*","/"};
char *comparison[6]={"<","<=","=",">",">=","<>"};
char *interpunction[6]={",",";",":=",".","(",")"};
//////////////////////////////////////////////////////////////////////////////////////////
int search(char searchstr[],int wordtype)
{
 int i;
 switch (wordtype)
 {
 case 1:for(i=0;i<=7;i++)
     {
      if(strcmp(keyword[i],searchstr)==0)
       return(1);
      
     }
 case 2:{
  for(i=0;i<=3;i++)
  {
   if(strcmp(operatornum[i],searchstr)==0)
    return(1);
  }
  break;
     }
 case 3: for(i=0;i<=5;i++)
   {
    if(strcmp(comparison[i],searchstr)==0)
     return(1);
   }
 case 4: for(i=0;i<=5;i++)
   {
    if(strcmp(interpunction[i],searchstr)==0)
     return(1);
   }
  
 
 }
 return(0);
}