复件 zhushizifu.cpp

这是我课程设计的时候编的一个simple 语言的词法分析器,可以运行,希望大家支持

//#include "stdafx.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <malloc.h>
#include <ctype.h>
#include <conio.h>
#include <iostream>    /*.....*/
using namespace std;   /*.....*/
#define NULL 0
FILE *fp;
char ch;
char *key1[33]={"and","array","begin","bool","call","case","char","constant","do","else",
					"end","false","for","if","input","integer","not","of","or","output",
					"procedure","program","read","real","repeat","set","then","to","true",
					"until","var","while","write"};
char *key2[12]={"我","(",")","*","我","+",",","-",".","..","我","我"};
char *key3[11]={":",":=",";","<","<=","<>","=",">",">=","[","]"};
//查找表
bool search(char searchstr[],int wordtype)
{
 int i;
 switch (wordtype)
 {
 case 1:for(i=0;i<=32;i++)
		{
           if(strcmp(key1[i],searchstr)==0)
		   { printf("<%d,%s>\n",i+1,key1[i]);
	         return(true);
		   }
		}
 case 2:{
  for(i=0;i<=12;i++)
  {
   if(strcmp(key2[i],searchstr)==0)
   {  printf("<%d,-->\n",i+38);
      return(true);
   }
  }
  break;
     }
 case 3: for(i=0;i<=10;i++)
   {
    if(strcmp(key3[i],searchstr)==0)
		{   //printf("<%d,%s>\n",i+50,key3[i]);
		    printf("<%d,-->\n",i+50);
			return(true);
		}
   }
  //default:cout<<"error!"; /*......*/
 }
 return(false);
}
//字母处理
char letterpro (char ch)//字母处理函数
{
 int i=-1;
 char letter[20];
 while (isalnum(ch)!=0)
 {
  letter[++i]=ch;
  ch=fgetc(fp);
 };
 letter[i+1]='\0';
 if (search(letter,1))//key1
        ;
 else
		printf("<biaoshi,%s>\n",letter);
 return(ch);
}
char numberpro(char ch)//数字处理程序
{
   int i=-1;
   char num[20];
   while (isdigit(ch)!=0)
   {
      num[++i]=ch;
      ch=fgetc(fp);
   }
   if(isspace(ch)!=0)//整常数
   {  
	   num[++i]='\0';
	   printf("<35,%s>\n",num);
	}
   if(ch=='.')//实符常数
   {   num[++i]='.';
       ch=fgetc(fp);
	   while (isdigit(ch)!=0)
		{
          num[++i]=ch;
          ch=fgetc(fp);
		}
	   num[++i]='\0';
	   printf("<36,%s>\n",num);
	}
   
  if(isalpha(ch)!=0)
  {
     while(isspace(ch)==0)
	 {
       num[++i]=ch;
            ch=fgetc(fp);
	 }
     num[i+1]='\0';
     printf("错误！非法标识符：%s\n",num);
     goto u;
  }
    num[i+1]='\0';
    u: return(ch);
  
}
//注释处理
char zhushipro(char ch)
{ char zhushi[20];
  int i=-1;
  ch=fgetc(fp);
  //if(ch!='*') {printf("<48,-->\n");goto u;}
  if(ch=='*')
	{ printf("<49,-->\n");
	  zhushi[++i]=ch;
      ch=fgetc(fp);
	 	
      m:while(ch!='*') {zhushi[++i]=ch;ch=fgetc(fp);}
        if(ch=='*')
		{  zhushi[++i]=ch;
		   ch=fgetc(fp);
           if(ch=='/')
			{  printf("<42,-->\n");ch=fgetc(fp);goto u;}
	       if(ch!='/')
		   { zhushi[++i]=ch;ch=fgetc(fp);goto m;}
		 
		}
	  //goto u;
  }
  if(ch!='*') {printf("<48,-->\n");goto u;}
 u: return (ch);
 }
char zifupro(char ch)
{ int i=-1;
  char zifu[10];
  printf("<38,-->\n");
  ch=fgetc(fp);
  while(ch!='\'')
  {  zifu[++i]=ch;
     ch=fgetc(fp);
	 //if(i>20)//字符常数长度〉50，出错
	 //{  cout<<"too long zifuchuan\n";
	   // goto u;
	 //}
	}
  
  if(ch=='\'')
	 { zifu[++i]='\0';
       printf("<37,%s>\n",zifu);
       printf("<38,-->\n");
	   ch=fgetc(fp);
		}
return (ch);
}
char otherprocess(char ch)
{
 int i=-1;
 char other[20];
 if (isspace(ch)!=0)
 {
   ch=fgetc(fp);
   goto u;
 }
 while ((isspace(ch)==0)&&(isalnum(ch)==0))
 {
   other[++i]=ch;
   ch=fgetc(fp);
 }
 other[i+1]='\0';
 if (search(other,2))
    ;  
 else
   if (search(other,3))
    ;
 else 
    printf("错误！非法字符：%s\n",other);
u: return (ch);
}
void main ()
{
 char str,c;
 printf("词法分析器\n");
 if ((fp=fopen("源程序.txt","r"))==NULL)
  printf("源程序无法打开！\n");
 else
 {
  str =fgetc(fp);
  while (str!=EOF)
  {
   if (isalpha(str)!=0)
      str=letterpro(str);
   else if(isdigit(str))
	   //(str<='9'&&str>='0')
        str=numberpro(str);
   else if(str=='/')
		 str=zhushipro(str);
   else if(str=='\'')
	     str=zifupro(str);
   else
        str=otherprocess(str);
  
  };
  printf("词法分析结束！\n");
  printf("点任意键退出!\n");
 }
   c=getch();
}