Debian Programming :: Check If Files Exists By Read Input From A File

I need a script that dose the following checks if files exists by read input from a file then compares them to the files listed in the directory if they don’t exists the script would report back which file dose not exists. I also need to format the output so that files are grouped in different groups, group A, B, and C and etc based on file name. I would like the output of that do not exists files to be sorted based on second number in the file name than group according. I understand some of the basics of bash scripting something along of the lines of a loop and if statements might do the trick. Below is what I have so far. I don’t car so much about the script reporting back the file exists I prefer to only know if the file is missing and is less than 3 days old. Problem is if a file dose not exists in the reports file the test compares against the wrong file.

Group A

Foo22000.tar.gz
Foo22010.tar.gz

Group B

foo25000.tar.gz
foo25100.tar.gz

Group C

foo26000.tar.gz

Code] ....