read files from multiple folders in for loop

I have for loop code which performs two kinds of opearation with files in the two diffferent folder.

For instance, first part of the code delas with files located in the Folder A, second part of the code deals with Folder A1 which is located inside Folder A. How to exceute this ???. Thanks in advamce for support..

[Mathieu NOE]

hello

look help for fullfile