正确的.cpp

编译词法分析器的源代码！

#include<stdio.h>
#include<string.h>
#include<ctype.h>
#include<iostream.h>
#define SIZE 128
#define NONE -1
#define FILENAME  "c:\\cifa.txt"

char ch;
int r;
int i;
int j;
int lineno=1;
char token[SIZE];
get_char();
void cleartoken();
char lexbuf[SIZE];
void concat();
void printf_id(char s[50],int a);

void main ()
{
    int f=0;
	int e;
	printf("lexical analysis begin now---\n");
	printf("IF YOU WANT INPUT FROM THE KEYBOARD,PLEASE PUT 0!\n");
	printf("IF YOU WANT INPUT FROM THE TEXT,PLEASE PUT 1!\n");
	scanf("%d",&e);
	if(e==1)
	{
	FILE *fp;
  //  char str[10];
 //  puts("Please iuput a file name()");
  // gets(str);
 //  scanf("%s/n",&str);
//	while(fopen(NAME,"r")==NULL)
 //  {
 //  puts("Error!");
 //  gets(str);
 //  }
if((fp=fopen(FILENAME,"r"))==NULL)
	{
	printf("cannot open this file\n");
	}
else    printf("File Begin:\n\n");
   fp=fopen(FILENAME,"r");
   while(feof(fp)==0)
   {
    lexbuf[f]=fgetc(fp);
    ++f;
   }				
	}
//if((fp=fopen(FILENAME,"r"))==NULL)
//	{
//	printf("cannot open this file\n");
//	}
 //   printf("File Begin:\n\n")

	else if(e==0)
	{
		puts("riweir\n");
		printf("please input your words.\n");
		printf("uu\n");
  //    gets(lexbuf);
	cin.get(lexbuf,SIZE);
	//canf("%s",lexbuf);
        printf("uu\n");
		f=strlen(lexbuf);
		printf("%d\n",f); 	
	}
        r=0;
do{  
	ch=get_char();
	if(ch==' '||ch=='\t')
		{
		   ;
		}
	else if(ch=='\n')
		{ 
			cleartoken();
			lineno++;
		}
	else if(isdigit(ch))
		{  
		   concat();
           ch=get_char();
           printf("digit ertey :\n");
	       while(isdigit(ch))
		   {
		   concat();
		   ch=get_char();
		   }

	   	printf("digit 12:%s\n",token);
        
	    	--r;
          cleartoken();
	}	
	else if(isalpha(ch))
		{
		 concat();
	     ch=get_char();
	    while(isalnum(ch))
		{
		concat();
        ch=get_char();
		}  
	  if(strcmp(token,"begin")==0)
		printf_id(token,1);
      else if(strcmp("end",token)==0)
		printf_id(token,2);	   
      else if(strcmp("if",token)==0)
		printf_id(token,3);	   
      else if(strcmp("then",token)==0)
		printf_id(token,4);      
      else if(strcmp("for",token)==0)
		printf_id(token,5);       
      else if(strcmp("do",token)==0)
		printf_id(token,6); 	   
      else if(strcmp("while",token)==0)
		printf_id(token,7);        
      else if(strcmp("var",token)==0)
		printf_id(token,8); 	   
      else if(strcmp("integer",token)==0)
		printf_id(token,9); 
      else if(strcmp("real",token)==0)
		printf_id(token,10);
      else printf("iden 11:%s\n",token);
        	--r;
            cleartoken();
	}
	else if(ch=='(')
		{
			printf("symb 23: (\n");
		    cleartoken();
		}
	else if(ch=='/')
		{
       ch=get_char();
       if(ch=='*')
			 {
                ch=get_char();
                while(ch!='*'||lexbuf[r]!='/')
				  { 
				     ch=get_char();
				  }
                ch=get_char();
               cleartoken();
			 }
        
       else if(ch=='/')
			{
                ch=get_char();
                while(ch!='\n')
                ch=get_char();
             
                cleartoken();
	   }
	 else { 
			printf("symb 23: /\n");
            --r;
		 }
		}
	else if(ch=='>')
		{
			  ch=get_char();
	         if(ch=='=')
		         printf("symb 19:>=\n");
	         else { printf("symb 18:>\n");
                    --r; 
			 }
	      cleartoken();
		}
     else if(ch=='<')
		{
			ch=get_char();
	        if(ch=='=')
		        printf("symb 21:<=\n");
	        else
	           { printf("symb 20:<\n");
		     	--r;
			}
	            cleartoken();
		}
	else if(ch==':')
	 {
		ch=get_char();
		if(ch=='=')
		 printf("symb 13: :=\n");
		else {  printf("symb 13: :\n");
			--r;}
	 }	 
    else if(ch=='+')
	 {
		 printf("symb 14: +\n");
	 }
    else if(ch=='-')
	 {
		 printf("symb 15:-\n");
	 }
    else if(ch=='*')
	 {
		 printf("symb 16:*\n");
	 }

    else if(ch=='=')
	 {
		 printf("symb 22: =\n");
	 }

    else if(ch==';')
	 {
		 printf("symb 23: ;\n");
	 }
    else if(ch==',')
	 {
		 printf("symb 24: ,\n");
	 }

	else if(ch==')')
	 {
		 printf("symb 26: )\n");
	 }
	}while(r<=f);
}
get_char()
{   
	char w;
	w=lexbuf[r];
	r++;
	return (w);
}
void printf_id(char s[50],int n)
{
	printf("word %d:%s\n",n,s);
}
void cleartoken()
{
	int len;
	for(len=0;len<SIZE;len++)
		token[len]='\0';
}
void concat()
{
	int len;
	len=strlen(token);
	token[len]=ch;
}