给定以下XML文件，完成算法流程图。

 

  
    

   
     
   
     <
   
     FileSystem
   
     >
   
      

   
     <
   
      DriverC 
   
     >
   
      

   
     <
   
     Dir 
   
     DirName
   
     =”MSDOS622”> 

   
     <File FileName 
   
     =” 
   
     Command.com” 
   
     ></
   
     File
   
     >
   
      

   
     </
   
     Dir
   
     >
   
      

   
     <
   
     File 
   
     FileName 
   
     =”MSDOS.SYS” 
   
     ></
   
     File
   
     >
   
      

   
     <
   
     File 
   
     FileName 
   
     =” 
   
     IO.SYS” 
   
     ></
   
     File
   
     >
   
      

   
     </
   
     DriverC
   
     >
   
      

   
     </
   
     FileSystem
   
     >
   
      

  
    

 

请画出遍历所有文件名（FileName）的流程图(请使用递归算法)。
答：

 

  
    

   
     
   
     void
   
      FindFile( Directory d ) 
{ 
 FileOrFolders 
   
     =
   
      d.GetFileOrFolders(); 
 
   
     foreach
   
     ( FileOrFolder fof 
   
     in
   
      FileOrFolders ) 
 { 
 
   
     if
   
     ( fof 
   
     is
   
      File ) 
 You Found a file; 
 
   
     else
   
      
   
     if
   
      ( fof 
   
     is
   
      Directory ) 
 FindFile( fof ); 
 } 
}