Thanks for taking time to take look at my code.
I think you misunderstand my issues. The issues is that I have two files and each files has the multiple sections, and each section contents the description of it. The problem I am want to do is to compare two files and only print out the sections and subsection within that are not in file1 and save to the third file. So far, my code print out the diff(file2)of the sections that are not in file1 but it does not print out the subsections that belongs to the section.
Please help me figure out what is the issues with my code.
Thanks so much in advance.