zzzzz.cpp

一个词法分析的小程序 用vc++6.0做的 比较简单 还能用

#include<stdlib.h>
#include<stdio.h>
#include<string.h>
FILE *fp,*fp1,*fp2,*fp3,*fp4,*fp5,*flp;
char ch,t;
char cch[50];
int k,m;


//char get()
//{  
  //int t; 
  //t=fgetc(fp);
  //if(t=='\n'||t=='\t'||t=='\r') t=' ';
  //return t;
//}

int SearchKey(char *cch )
{
	char *StrToken[32]={"auto","break","case","char","const",
		"continue","default","do","double","else","enum","extern",
		"float","for","goto","if","int","long","register","return",
        "short","signed","sizeof","static","struct","switch",
		"typedef","union","unsigned","void","volatile","while"};
	  for(int i=0;i<32;i++)
	  {
	  if(strcmp(StrToken[i],cch)==0)	  
		 return i;	  
	   }

	  return 0;
}
void nextget()
{
	
	//char *word;
	//int result;
	ch=getc(fp);
	 while(ch==' '||ch=='\t'||ch=='\n'||ch=='\r')
	{
		 ch=getc(fp);
	 }
	//if(ch=='\n')
		//return;
	if((ch>='A'&&ch<='Z')||(ch>='a'&&ch<='z')||(ch=='_'))
	{
		while((ch>='A'&&ch<='Z')||(ch>='a'&&ch<='z')||(ch>='0'&&ch<='9')||(ch=='_'))
		{
			cch[k]=ch;
			k=k+1;
			ch=getc(fp);
		}
		if(SearchKey(cch)==0)
		{	
			fprintf(fp1,"%s\n",cch);
		     fseek(fp,-1L,SEEK_CUR);
		}
		else 
		{
			fprintf(fp2,"%s\n",cch);
		     fseek(fp,-1L,SEEK_CUR);
		}
		return;
	}
	   
	else if(ch>='0'&&ch<='9')
	{
		while(ch>='0'&&ch<='9')
		{
			cch[k]=ch;
			k=k+1;
			ch=getc(fp);
		}
		fprintf(fp3,"%s\n",cch);
		fseek(fp,-1L,SEEK_CUR);
		return;
	}
	
	else if(ch=='+'||ch=='-'||ch=='*'||ch=='/')
	{
		cch[k]=ch;
		//k=k+1;
		ch=getc(fp);
		if(ch!=EOF)
		{
			//cch[k]=ch;
			if(cch[k]==ch)
			{
				k=k+1;
				cch[k]=ch;
				fprintf(fp4,"%s\n",cch);
				//fseek(fp,-1L,SEEK_CUR);
				return;
			}
			if(ch=='=')
			{
				k=k+1;
				cch[k]=ch;
				fprintf(fp4,"%s\n",cch);
				//fseek(fp,-1L,SEEK_CUR);
				return;
			}
			if((ch>='A'&&ch<='Z')||(ch>='a'&&ch<='z')||(ch=='_')||(ch>='0'&&ch<='9'))
			{
				fprintf(fp4,"%s\n",cch);
				fseek(fp,-1L,SEEK_CUR);
				return;
			}
			k=k+1;
			cch[k]=ch;
			fprintf(fp5,"%s\n",cch);
			//fseek(fp,-1L,SEEK_CUR);
			return;
		}
	}
	else if(ch=='('||ch==')'||ch=='['||ch==']'||ch=='{'||ch=='}')
	{
		fprintf(fp4,"%s\n",cch);
		//fseek(fp,-1L,SEEK_CUR);
		return;
	}
	
	else if(ch=='|'||ch=='!'||ch=='<'||ch=='>'||ch=='='||ch=='\'')
	{
		cch[k]=ch;
		//k=k+1;
		ch=getc(fp);
		if(ch!=EOF)
		{
			//cch[k]=ch;
			if(ch==cch[k])
			{
				k=k+1;
				cch[k]=ch;
				fprintf(fp4,"%s\n",cch);
				//fseek(fp,-1L,SEEK_CUR);
				return;
			}
			if((ch>='A'&&ch<='Z')||(ch>='a'&&ch<='z')||(ch=='_')||(ch>='0'&&ch<='9'))
			{
				fprintf(fp4,"%s\n",cch);
				fseek(fp,-1L,SEEK_CUR);
				return;
			}
			k=k+1;
			cch[k]=ch;
			fprintf(fp5,"%s\n",cch);
			//fseek(fp,-1L,SEEK_CUR);
			return;
		}
		
		
		
	}

  
  
  

 
  

}
void main()
{
  fp1=fopen("b.txt","w");
  fp2=fopen("g.txt","w");
  fp3=fopen("s.txt","w");
  fp4=fopen("f.txt","w");
  fp5=fopen("c.txt","w");
  char name[30];
  
  
  printf("请输入文件名：");
  scanf("%s",name);
  fp=fopen(name,"r");
  //ch=fgetc(fp);
  if (fp==0)
  {
	  printf("文件为空！");
	  return;
  }
  //fp=fopen(name,"w");
  while (ch!=EOF)
  {
	  k=0;
	  nextget();
	  memset(cch,0,50);
  }



}