I have multiple separate CSV files that are just a single column list of email addresses, where each file represents a 'tag' associated with that email. I'd like to merge them into one CSV file, such that all email addresses in any files are listed in the first column, and all other columns are the file names and a true/false or 1/0 if the email is in that file.
Which software would have this feature, and how would I implement it? I own the latest version of Excel if that can do it.