text1.txt

一个由c++编程的c语言的词法分析程序源代码

#include<stdio.h>
#define MSIZE 20
char buffer[MSIZE];

struct output
	{
		char fuhao;
        int  leixing;
		
	};

void cifa(char c,output *o)
{
	output output1;

	output1.fuhao=c;
	o->fuhao=c;
	switch(c)
	{


	case 'a':
	case 'b':
    case '(':
	case ')':
	case 'd':
	case 'e':
		{
		output1.leixing=1;
		o->leixing=1;
		break;
		}
	case 'A':
	case 'B':
    case 'S':
		{
		output1.leixing=2;
		o->leixing=2;
		break;
		}
	default:
		printf("%c not a token\n",c);
		break;
	}
	

		}

void main()
{
	char c=NULL;
  printf("input expression\n");
  int count=scanf("%s",&buffer);
  printf("%s\n",buffer);

  char *p=buffer;
	
  while(*p!='\0')
    {	
	output o;
	cifa(*p,&o);
    if(output1.leixing==1||output1.leixing==2)
	printf("%d,%c\n",o.leixing,o.fuhao);

				p++;
  }
  
	return ;
}