#include <stdio.h>
#include <conio.h>
#include <dos.h>
#include <dir.h>
#include <string.h>
#include <alloc.h>

struct btreenode
{
    struct btreenode *leftchild ;
    char data[13] ; /* file name */
char *loc ; /* location of filename */
struct btreenode *rightchild ;
} *bt = NULL ;

void disktree( ) ;
int insert ( struct btreenode  **, char*, char* ) ;

void main( )
{
    char current_dir[32] ;

    clrscr( ) ;

    getcwd ( current_dir, 32 ) ;
    chdir ( "\\" ) ;
    disktree( ) ;
    chdir ( current_dir ) ;

    getch( ) ;
}

void disktree( )
{
    struct ffblk file ;
    int flag ;
    char loc[80] ;

    getcwd ( loc, 80 ) ;
    flag =  findfirst ( "*.*", &file, FA_NORMAL | FA_RDONLY | FA_HIDDEN | 
                    FA_SYSTEM | FA_LABEL | FA_DIREC | FA_ARCH ) ;

    while ( flag == 0 )
    {
        if ( file.ff_name[0] != '.' )
        {
            if ( file.ff_attrib == FA_DIREC && file.ff_fsize == 0 )
            {
                chdir ( file.ff_name ) ;
                disktree( ) ;
                chdir ( loc ) ;
            }
            else
                insert ( &bt, loc, file.ff_name ) ;
        }
        flag = findnext ( &file ) ;
    }
}

/* inserts a new node in a binary search tree */
int insert ( struct btreenode  **sr, char* l, char* f )
{
    char *p ;
    int flag ;

    if ( *sr == NULL )
    {
        *sr = ( struct btreenode * ) malloc ( sizeof ( struct btreenode ) ) ;

        if ( *sr == NULL )
        {
            printf ( "\nOut of memory." ) ;
            exit ( 1 ) ;
        }

        ( *sr ) -> leftchild = NULL ;
        ( *sr ) -> rightchild = NULL ;
        strcpy ( ( *sr ) -> data, f ) ;
        p = ( char * ) malloc ( ( strlen ( l ) + 1 ) ) ;

        if ( p == NULL )
        {
            printf ( "\nOut of memory." ) ;
            exit ( 1 ) ;
        }

        strcpy ( p, l ) ;
        ( *sr ) -> loc = p ;
    }
    else
    {
        flag = strcmp ( ( *sr ) -> data, f ) ;

        if ( flag == 0 )
        {
            printf ( "org: %s", ( *sr ) -> loc ) ;

            if ( strlen ( ( *sr ) -> loc ) > 4 )
                printf ( "\\" ) ;

            printf ( "%s\n", ( *sr ) -> data ) ;
            printf ("dup: %s", l ) ;

            if ( strlen ( l ) > 4 )
                printf ( "\\" ) ;

            printf ( "%s\n\n", f ) ;
        }
        elseif ( flag < 0 )
            insert ( &( ( *sr ) -> leftchild ), l, f ) ;
        else
            insert ( &( ( *sr ) -> rightchild ), l, f ) ;
    }
    return ;
}