新建 文本文档.txt

利用Ｃ＋＋语言实现DOS界面下Ｃ＋＋源程序的编译分析功能.

#include <fstream>
#include <string>
#include <iostream>
#include <iomanip>
using namespace std;
int isKey(char *str);

/****************************保留字集合***************************/
char* keyword[]={"_asm", "auto", "bad_cast", "bad_typeid","bool",
                "break" ,"case" ,"catch","char","class",
                "const","const_cast","continue" ,"default" ,"delete" ,
                 "do","double", "dynamic_cast", "else", "enum",
				 "except" ,"explicit" ,"extern" ,"false","finally", 
				 "float", "for", "friend","goto", "if", 
				 "include","inline", "int","long", "mutable",
				 "namespace", "new","operator", "private", "protected",
				 "public","register", "reinterpret_cast", "return", "short",
				 "signed", "sizeof", "static", "static_cast","struct",
				 "switch", "template", "this","throw","true", 
				 "try", "type_info","typedef", "typeid", "typename", 
				 "union","unsigned", "using", "virtual","void",
				 "volatile", "while","main","iostream"
};

/*****************************是不是标志符*******************************/
int identf(char *str)
{
 int flag=0;
 char *p=str;
 /*判断第一个字符是否符合*/
 if((*str>='a' && *str<='z') || (*str>='A' && *str<='Z') || *str=='_')
 {
  flag=1;
  str++;
 }
 /*从第二个字符开始遍历判断*/
 while(*str && flag)
 {
  if((*str>='a' && *str<='z') || (*str>='A' && *str<='Z') || *str=='_'
   || (*str>='0' && *str<='9'))
  {
   flag=1;
   str++;
  }
  else
   flag=0;
 }
 
 /*判断是不是关键字*/
 if(flag)
  flag=isKey(p);
 return flag;
}

/*****************************是不是关键字*******************************/
int isKey(char *str)
{
 int i, flag=1;

 for(i=0; i<69; i++)
 {
  if(strcmp(str, keyword[i])==0)
  {
   flag=0;
   break;
  }
 }

 return flag;
}

/*****************************主函数*******************************/


int main (int)
{   
	ifstream inf;
    ofstream outf;
    char c;
    char *buf=new char[256];
    int i;
	inf.open("in.txt");
	outf.open("out.txt");
	inf >> noskipws; 

    while(inf >>c)
    {
		i=0;

		/****************************换行***************************/
        if (c == '\n'){  
            //outf << "\n";        
            //cout << "\n"; 
			continue;
        }

        /*****************************符号处理**********************/
        if(c>='!'&&c<='/'  ||  c>=':'&&c<='@'  ||  c>='['&&c<='`' || c>='{'&&c<='~')
		{
        /*****************************判断注释**********************/
			if(c=='/')
			{
			
			}
			cout<<c;
			outf<<c;
			cout<<"  特殊符号"<<endl;
			outf<<"  特殊符号"<<endl;
		}

        /*****************************符号处理**********************/
       else  
	   {                
        while((c>='a' && c<='z') || (c>='A' && c<='Z') || c=='_'
             || (c>='0' && c<='9'))
 { 
             buf[i++]=c;
             inf>>c;
 }
	
  buf[i]='\0';
 if(!isKey(buf))
 {
	 for(int j=0;j<i;j++)
	 {
		 cout << buf[j];
		 outf<< buf[j];
	 }
		
	    cout<<"  关键字"<<endl;
		outf<<"  关键字"<<endl;
 }
 else if(identf(buf))
 {
    for(int j=0;j<i;j++)
	{
		cout << buf[j];
		outf<< buf[j];
	}
        cout<<"  标识符"<<endl;  
		outf<<"  标识符"<<endl;
	
	}
			//outf << c;    
        }
    }


    inf.close();
    outf.close();
    return 0;
}