Smartest way

[Technocrat]

Here is what I want to do:

Lets say for example I have 10 directories as followes:

c:\temp
c:\temp\sub1
c:\temp\sub2
c:\temp\sub3
c:\temp\sub1\node1
c:\temp\sub1\node2
c:\temp\sub2\node1
c:\temp\sub2\node2
c:\temp\sub2\node3
c:\temp\sub2\node4

I want to keep track of which directories have files or not, if they do how many, and do they have certian types of files.

So lets say c:\temp\sub2\node3 has main.cpp file in. When a user chooses that file which will be in a list, my program can quickly look up which directory its in.

Whats the smartest/quickest way to do this? Class, Linked List/Vector, Map, Other?

Thanks for your suggestions