Accessing directories and sub-directories.

[homesick123]

Hi
I am very new to perl.I want to write a script which will access the directories and their sub-directories.For eg.

-default
----main
-------dir1
----------
------------
----------

----------
-----------
-----------x
-------dir2
-----------
-------dir3
------------folder1
----------sub1
-----------y
------------folder2
----------sub2
-----------z

Now for the above folder structure I want a script that will take me to the last directory (x,y,z in the above case) .Everytime the script goes to the last folder it must generate the path followed .
eg.default/main/dir3/folder1/sub1/y
This generated path has then got to be passed on to an external file as a variable.
What I make out here is that I need
1) conditional loop - condition is:Are there any more folders(not individual files) inside the current folder?If Yes ,go to 2). If No ,go to 3).
2) open the folder .go to 1).
3) generate the absolute path. where , $path = absolute path
4) external file uses $path
5) end

[homesick123]

actually this is the folder structure

-default
----main
-------dir1
###### ----------(sub folder of dir1)
------------
###### ----------

###### ----------
########### -----------
################## -----------x
-------dir2
###### -----------(sub folder of dir2)
-------dir3
------------folder1
###### ----------sub1
#################-----------y(sub folder of sub1)
------------folder2
###### ----------sub2
############## -----------z